St. Elizabeths Landscape Integration Plan

Page 1

General Services Administration

Department of Homeland Security

ST. ST. ELIZABETHS ELIZABETHS WEST CAMPUS WEST CAMPUS Volume Two

Landscape Integration Plan Hardscape, Vegetation, Soils & Stormwater Coordination Perkins +Will Heritage Landscapes, LLC GeoConcepts Engineering , Inc. Morris Arboretum William H. Gordon & Associates Craul Land Scientists Horton Lee Brogden Lighting Design Continental Conservation



ST. ELIZABETHS WEST CAMPUS Volume Two

Landscape Guidance Three Volume Set Volume I:

St. Elizabeths West Campus Landscape Preservation Plan

Volume II:

St. Elizabeths West Campus Landscape Integration Plan

Volume III:

St. Elizabeths West Campus Landscape Management Plan

Based in respect for the National Historic Landmark landscape, this volume provides a detailed description of historic landscape character and features, recommends preservation and rehabilitation of the landscape, and, on that basis, defines an overall vision for the 2016 campus.

Presents integrated strategies for the implementation of the 2016 plan, through the coordination of multiple design and construction projects. Provides detailed guidance for vegetation, soils, stormwater, circulation, furnishings, details, service and security needs of the rehabilitated campus.

Details the stewardship of the 2016 rehabilitated campus, through character based landscape management and landscape maintenance, to establish the care regimes for National Historic Landmark landscape post-construction, to ensure that historic integrity and character are retained into the future.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents

Acknowledgements Many people have been involved in the process of developing this report. Heritage Landscapes LLC has been a significant partner in the development of design guidance for the individual projects within the St Elizabeths West Campus.

The General Services Administration (GSA),

Department of Homeland Security (DHS), Perkins + Will architects, William H. Gordon Associates, Inc. WHGA (civil engineering), Greenhorne & O’Mara (survey and civil engineering), GeoConcepts Engineering, Inc. (hydrogeological investigations), Craul Land Scientists (soils), Continental Conservation (ecologist/environmental biologist), and the Morris Arboretum (arborists) have all contributed ideas, thoughtful review, and technical detail to support the findings in this report.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents

Table of Contents List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x CHAPTER I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Approach to the Landscape Integration Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Site Issues to be Further Studied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 CHAPTER II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Cultural and Historical Significance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Site Physiographic Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Site Soil Assessment

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Vegetation and Habitat Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Site Hydrology Assessment

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Site Environmental Regulatory Zones & Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 CHAPTER III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Design Guidance Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Project Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Historic Landscape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Design Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Site Soil Assessment

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Design Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Vegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Design Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Proposed Landscape Types

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents Historic Gardens and Courtyards

39

Individual Trees

40

Historic Cemetery and Cemetery Woodland

44

Natural Landscapes – Meadows, Woodlands and Forest

46

Site Circulation, Access, & Hardscape Improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Design Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Vehicular Circulation

52

Passenger (VIP) Vehicle Movement

54

Delivery Service Network

54

Maintenance/ Waste Removal Network

54

Emergency and Fire Network

55

Shuttle Bus Routes

55

Pedestrian Circulation

56

ADA Accessibility Guidance

57

Site Amenities

58

Design Character & Hardscape Materials framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Design Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Roads and Curbs

59

Pedestrian Crosswalks andPavement Markings

60

Pedestrian Walks, Building Edges/ Plazas, and Edge Restraints

61

Landscape Furnishings

62

Site Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Overall Design Guidance

67

Security Considerations

68

Current Standards

68

IESNA – General Visual Issues

68

Lighting Goals

69

Research in New Technology

69

LED End of Life Issues

70

Exterior Lighting Diagrams

70

Site Signage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents Stormwater Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Design Guidelines for Proposed BMPs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Vegetated Swales

71

Cisterns

72

Infiltration Basins

73

Recharge Beds

74

Continuous Tree Trenches

75

Green Streets

75

“Passive Irrigation”

75

Major Stormwater Outfalls

76

Watersheds

76

CHAPTER IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Development and definitionof construction phasing sequencing and strategy . . . . . . . . . . . . . . . . . 79 Construction Phasing, Access, and Staging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 Time Sensitive Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Site Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Soil salvage, rehabilitation and Installation1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Vegetation establishment and rehabilitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Hardscape, site elements and furnishings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Stormwater Management Details for the St. Elizabeths West Campus . . . . . . . . . . . . . . . . . . . . . . 175 CHAPTER V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 Site Utilities Coordination andPreservation of Historic Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 Schematic Design Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 CHAPTER IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Leed® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Sites™ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 Process and Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 Pre-design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 Monitoring Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Progress Scorecard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents Appendix A Related Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Appendix B Soil Investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 Appendix C St. Elizabeths Tree Database - Bartlett Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Appendix D St. Elizabeths Tree Database – Greenhorne & O’Mara Tags . . . . . . . . . . . . . . . . . . . . . 299 Appendix E Tree Data Procedure Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 Appendix F Individual Tree Assessment Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 Appendix G Existing Native Plant Community Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 Appendix H Existing Native Plant Community Classification Methodology . . . . . . . . . . . . . . . . . . . . 315 Appendix I Existing Forest Assessment Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 Appendix J Maryland & Virginia’s Invasive Species List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325 Appendix K Forest Age Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333 Appendix L Morris Arboretum Cemetery Tree Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335 Appendix M Morris Arboretum Plateau Tree Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349 Appendix N USDA’s Non-Native Invasive Plants for Southern Forests . . . . . . . . . . . . . . . . . . . . . . . . 363 Appendix O Plant Species List for Native Plant Community Structures . . . . . . . . . . . . . . . . . . . . . . . 365 Appendix P Site Lighting Master Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389 Appendix Q Hydrogeological Investigation Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391 Appendix R Stormwater Modeling, Analysis & Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Table of Contents

List of Figures Overview: 1. 1937, 2009, 2016 Land Use Comparison 2. 2016 Landscape 3. Project Area Plan 4. Site Protection Zones and Construction Areas Physiography: 5. Ecoregion and Physiography 6. Site Physiography and Slopes 7. Site Aspect Soil: 8. Soil Analysis 9. Soil Salvage Opportunities 10. Woodland Suitability Map 11. Stormwater Management Suitability Map Vegetation: 12. Regional Context Plan 13. Existing Plant Communities 14. Individual Tree Assessment 15. Forest Assessment 16. Severity of Disturbance 17. Proposed Landscape Types 18. Forest and Meadow Management Priority 19. Proposed Natural Plant Community Structure 20. Target Natural Plant Communities Plan- primary 21. Target Natural Plant Communities Plan- secondary 22. Tree Protection Zones Plan 23. Tree Protection Zones – Enlargement Plans (1) 24. Tree Protection Zones – Enlargement Plans (2) 25. Tree Protection Zones – Enlargement Plans (3) 26. Tree Protection Zones – Enlargement Plans (4) Circulation + Hardscape: 27. Campus Roadways 28. Delivery Service Network 29. Maintenance / Waste Removal 30. Emergency / Fire Network 31. Shuttle Bus Route 32. Campus Walks 33. Pedestrian Flow Analysis AM/PM 34. Pedestrian Flow Analysis Midday 35. ADA Slope Analysis 36. Landscape Amenities

37. Site Lighting 38. Security Lighting Stormwater: 39. Regional Watersheds 40. Pre-Development Watersheds 41. Upper Aquifer Zone: Groundwater Contour Map 42. Upper Aquifer Zone: North View 43. Upper Aquifer Zone: South View 44. Groundwater and Site Development: Pre-Development 45. Groundwater and Site Development: Typical Construction 46. Groundwater and Site Development: Proposed Strategy 47. Post Development Watersheds 48. Stormwater Management Concept 49. Stormwater Management: North View 50. Stormwater Management: South View 51. Ground Cover Study Phasing: 52. Limits of Disturbance 53. Proposed Laydown 54. Phasing and Access: Phase 1A 55. Phasing and Access: Phase 1B 56. Phasing and Access: Phase 2A 57. Phasing and Access: Phase 2B 58. Phasing and Access: Phase 3A 59. Phasing and Access: Phase 3B Utilities Coordination 60. Site Utilities Coordination and Historic Tree Protection Schematic Design 61. Schematic Concept Plans –Selected Design Areas 62. Center Building Pool: Schematic Design 63. Sweetgum Ravine: Schematic Design 64. Sweetgum Trails: Schematic Design 65. Sweetgum Trails: Section 66. Burroughs Cottage Ravine: Schematic Design Sustainability Rating Systems 67. LEED Credit Goals 68. Sustainable Sites Initiative Credit Goals

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References 1. Applied Environmental, 2005. Ash Characterization Report. Prepared for the U.S. General Services Administration. 2. Bartlett Tree Experts, 2007. Resource Conservation Enhancement: Mature Landscape Trees and Plants. Prepared for the U.S. General Services Administration. 3. District of Columbia Department of Health, 2003. “Storm Water Management Guidebook.” 4. District of Columbia Municipal Regulations and DC Register, 2010. “DC Municipal Regulation (DCMR) Title 21, Chapter 5.” http://www.dcregs.dc.gov/ 5. Fuller, T. C. and G. D. Barbe, 1985. “The Bradley method of eliminating exotic plants from natural reserves.” Fremontia 13:(2): 24-26. 6. Jones, Lang, LaSalle and SmithGroup, 2008. The DHS Headquarters Consolidation at St. Elizabeths Final Master Plan. Prepared for the U.S. General Services Administration. 7. Lake Superior Streams. 2009. “Site Design Tool Kit: Underground Storage.” LakeSuperiorStreams: Community Partnerships For Understanding Water Quality and Stormwater Impacts at the Head of the Great Lakes (http:// lakesuperiorstreams.org). University of Minnesota-Duluth, Duluth, MN 55812. 8. Natureserve, 2008. “NatureServe Explorer: An online encyclopedia of life” [web application]. Version 7.0. NatureServe, Arlington, VA. U.S.A. Accessed October 2009. Available http://www.natureserve.org/explorer. 9. Maryland Department of Agriculture, 2009. “Emerald Ash Borer Survey and Eradication Updates”. Maryland Department of Agriculture website. Updated October 13, 2009. Available http://www.mda.state.md.us/plants-pests/ eab/current.php 10. Maryland Invasive Species Council, 2009. “Invasive Species of Concern in Maryland: Terrestrial Plants.” http://www. mdinvasivesp.org/list_terrestrial_plants.html 11. Matsuoka, T., T. Ettel, and J. Parke. 2008. Meadows on the Menu: Recipes for creating a New Jersey Native Wildflower Meadow. New Jersey Audubon Society. 12. Miller, John, 2006. “Nonnative Invasive Plants of Southern Forests.” USDA Forest Service Southern Research Station

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General Technical Report SRS-62. 13. O’Donnell, Patricia M., et al, Heritage Landscapes LLC, 2010. St. Elizabeths West Campus Landscape Preservation Plan. Prepared for the U.S. General Services Administration. [issued at 75% draft as STE Landscape Preservation and Management Plan] 14. O’Donnell, Patricia M., Heritage Landscapes LLC, 2010. St. Elizabeths West Campus Landscape Management Plan. Prepared for the U.S. General Services Administration. 15. O’Donnell, Patricia M., Heritage Landscapes LLC and Robinson Judith, et al, Robinson & Associates, 2009. St. Elizabeths West Campus Cultural Landscape Report. Prepared for the U.S. General Services Administration. 16. Oliver, C.D. and Larson, B.C., 1996. Forest Stand Dynamics. New York, NY. John Wiley and Sons. 17. Rainbow Tree Care, 2010. “Tree Growth and Tree Health: Controlling Growth To Promote Healthy Trees In Urban Environments.” http://www.rainbowtreecare.com/ planthealth/tree-growth.asp). 18. Rossell, C.R., Patch, S. and Salmons, S. 2007. “Effects of deer browsing on native and non-native vegetation in a mixed oak-beech forest on the Atlantic Coastal Plain”. Northeastern Naturalist, 14 (1): 61-72. 19. Urban Forestry Administration, 2002. Urban Forestry Preservation Act of 2002. District of Columbia Department of Transportation. 20. Urban Tree Foundation, 2010. Guideline Specifications for Nursery Tree Quality www.urbantree.org/pdf/specs10-13.pdf 21. United States Fish and Wildlife Service, 2007. National Bald Eagle Management Guidelines. 22. United States General Services Administration, 2008. DHS Headquarters Consolidation at St. Elizabeths Environmental Impact Statement. 23. Virginia Department of Conservation and Recreation and Virginia Native Plant Society, 2009. “Invasive Alien Plant Species of Virginia.” http://www.dcr.virginia.gov/natural_ heritage/documents/invlist.pdf 24. Williams, G. P., 1977. “Washington, D.C.’s vanishing springs and waterways”. Geological Survey Circular 752, 19p.


CHAPTER I

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Introduction, Project Scope and Methodology

CHAPTER I

Introduction, Project Scope and Methodology

Introduction St. Elizabeths West Campus, located in southeast Washington’s Anacostia neighborhood, is a site of both regional and national historic significance and is a National Historic Landmark. As the campus is adapted for new use as federal government offices, the preservation and rehabilitation of the remaining historically significant landscapes need to be considered as outlined in the December 9, 2008, Section 106 Programmatic Agreement. The proposed redevelopment of the site under the guidance of the General Services Administration (GSA) to provide office facilities for the consolidated headquarters for the Department of Homeland Security (DHS) will involve rehabilitation of the majority of historic buildings for new offices and shared uses, as well as historically compatible new construction and renewal of the significant historic landscape. The three volumes of the Landscape Preservation and Management Plan (LPMP) provide philosophical consistency and promote responsible preservation practices to protect this unique cultural resource, with the Secretary of the Interior’s Standards as the basis for all project work. This three-volume LPMP along with the Master Plan and the Cultural Landscape Report will provide guidance and serve as a reference to GSA, user agencies, and design teams as they move forward with the rehabilitation for reuse, and the ongoing management and maintenance of this remarkable historic property. These reference documents can be summarized as follows: •

Master Plan – The DHS Headquarters Consolidation at St.. Elizabeths Final Master Plan completed in 2008 by Jones, Lang, LaSalle and SmithGroup sets the stage for the building and landscape planning and phasing necessary for the DHS consolidation.

Cultural Landscape Report – The Cultural Landscape Report, completed in 2009 by Heritage Landscapes, offers a detailed analysis of the history of the site and identifies historic landscape features. This report proposes a preservation and rehabilitation approach to the St... Elizabeths West Campus, in which remaining historically significant features are preserved, repaired and adapted appropriately to the new campus uses. In addition to highlighting the significant past, this report also provides a historically sensitive springboard for future plans of the campus.

Landscape Preservation and Management Plan – Although initially conceived as a single document, the Landscape Preservation and Management Plan has been divided into three volumes. As a coordinated entity, the documents provide guidance on the protection, rehabilitation, and ongoing maintenance appropriate to the St.. Elizabeths West Campus, aimed at retaining its historic character as it is adapted to its new use. Each volume focuses on specific client or consulting groups. Each volume emphasizes different phases of the landscape design process.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Introduction, Project Scope and Methodology The three volumes of the Landscape Preservation and Management Plan are:

Approach to the Landscape Integration Plan

1. Volume I: Landscape Preservation Plan (LPP) – The first volume, by Heritage Landscapes (2010), provides an overall description of the historic landscape, its character-defining features, and their protection and repair. This report also defines an overall vision for the 2016 campus, illustrating at a conceptual level the integration of historic and contemporary landscape features within the context of new campus use.

This report emphasizes an integrated landscape, one which coordinates site function, historic site protection and management strategies, environmental stewardship, stormwater management, utilities systems, and construction needs/ staging/ sequencing into a coherent plan. In this campus, new landscape interventions and features are intended to fulfill multiple roles, including historic rehabilitation and green infrastructure1 to support the upgraded campus. The plan will be implemented during a series of upcoming construction projects with an anticipated completion date of 2016. It is the intent of this report that, at the close of current projects, the site will have successfully integrated new institutional uses with the preservation and rehabilitation of the historic campus, to create a landscape that is healthier and more functional.

2. Volume II: Landscape Integration Plan (LIP) – The second volume by Andropogon Associates can be considered a ‘bridging document’, which supports the long-term goals outlined by the Landscape Preservation Plan. The Landscape Integration Plan presents coherent strategies for how to implement the 2016 plan between 2009 and 2016, through the coordination of multiple design and construction projects. This report provides further guidance on the integration of stormwater, vegetation, soil, circulation, environmental, servicing, and security needs into the historic landscape framework. 3. Volume III: Landscape Management Plan (LMP) – The third volume, by Heritage Landscapes (2010), is an on-going management guide for the historic landscape after the construction process is complete. It is intended for use by the GSA and others directed to ensure that the historic integrity of the site remains intact for future generations. A summary of these documents, their targeted audience and main objectives can be referenced in Table 1. In addition to their guidance, all of these works aim to fulfill the mandated stipulations of the Programmatic Agreement (GSA, ACHP, DCHPO, FHWA, NPS, NCPC, and DHS, 2008):

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Protection of Existing Resources

Site Management

Construction Staging

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GREEN INFRASTRUCTURE “Green Infrastructure” refers to the use of sustainable plant- and soil-based systems to provide environmental services such as stormwater management, flood control, and clean water supply in lieu of conventional engineered systems. Green Infrastructure includes both regional conservation strategies (greenways, wetland preservation) and site specific Best Management Practices such as vegetated swales, green roofs, rain gardens, and rainwater harvesting systems.

Findings from previous studies have been supplemented with additional field review and technical studies. Sitespecific soil assessments, geotechnical investigations of groundwater systems, and updates on tree health were conducted in the summer and fall of 2009. In particular, GeoConcepts Engineering is conducting a groundwater investigation, which is guiding the conceptual design stormwater management systems. Craul Land Scientists has reviewed the condition of site soil and their suitability for plant growth, stormwater management, and construction staging. The Morris Arboretum has conducted a health review of selected trees and surveyed additional trees in the woods around the Cemetery. Andropogon Associates staff were on site throughout the spring, summer and fall of 2009 to update the existing tree mapping (Bartlett, 2007; Bartlett 2008), and assess the condition of the woods. Continental Conservation walked the site in October 2009 to review the forest condition and provide a peer review of the forest assessment and management priorities. The intent has been to review the combined data and present it in a


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Introduction, Project Scope and Methodology form that highlights important issues and patterns relevant to the upcoming design and construction. An overview of the technical findings is presented in the body of this report, with detailed descriptions and results in the appendices. This report is divided into chapters based on the targeted user and what phase they are operating within- planning, design, construction documentation or construction activities: •

Chapter II of this report summarizes the existing site information. In many cases the data are very detailed, and come from a variety of sources. In these situations we have attempted to present the information in a way that highlights key resources and considerations relevant to design and construction.

Chapter III presents the overarching approach to the design phases of the campus landscape.

Chapter IV provides construction guidance, including phasing plans, conceptual details, and an overview of specifications appropriate to this site for those producing construction drawings and those involved in construction activities.

Chapter V introduces schematic design concepts for representative landscape project areas at St. Elizabeths West Campus as a starting point for landscape designers.

Chapter VI presents a summary of the benefits of integrated design and how these benefits also provide an opportunity for projects on the campus to apply and attain LEED and SITES accreditation.

Site Issues to be Further Studied The St. Elizabeths Campus will change significantly over the six years of construction. New information will become available for key issues highlighted in this report. Therefore, it is important that each Architectural / Engineering Team take responsibility to investigate these issues in greater depth as applicable to their respective projects. It is particularly crucial to reexamine the areas of steep slopes, the contaminated and easily erodible soils, the protection of historical trees from construction damage, and the protection of site users and elements from potential tree problems. Lastly, it is critical to investigate and understand the impacts of penetrating the perched water table and altering the groundwater flow, which is found approximately 9m below the present ground surface of the plateau.

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Table 1: ST. ELIZABETHS WEST CAMPUS- Overall Landscape Planning, Design and Construction Reference Documents

Comprehensive Documents For The DHS Consolidation Of St.... Elizabeths West Campus

Master Plan

Cultural Landscape Report (CLR)

Landscape Preservation Plan (LPP)

Landscape Integration Plan (LIP)

Landscape Management Plan (LMP)

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Primary Author (s) Primary Topic

Primary Users

Jones Lang LaSalle; SmithGroup

Master Planning

• GSA • DHS • All contractors (designers, specialists, general construction contractors)

Heritage Landscapes

Landscape Architecture/ Historic Landscape Preservation

• GSA • DHS • Reviewing parties

Heritage Landscapes

Landscape Architecture/ Historic Landscape Preservation

• GSA • DHS • Reviewing parties

Landscape Architecture/ Landscape Andropogon Associates Design and Construction Integration and Implementation

Heritage Landscapes

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Landscape Architecture/ Historic Landscape Preservation and Long-term Management

• GSA Project Managers • DHS • Architects • Engineers • All Contractors and Design Specialists • Maintenance Supervisors • • • •

GSA DHS Reviewing parties Maintenance supervisors


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Introduction, Project Scope and Methodology

Landscape Time Period Design Phase For Use For Use

Main Objectives

Planning

Programming, phasing and build-out plan for DHS consolidation/ “….programmatic requirements and functional and operational efficiency required by the Department of Homeland Security, while rehabilitating the NHL of St. Elizabeths to the maximum extent possible.”

2009 +

Planning and Design

Documentation of contributing landscape features/ “Record the complex evolution and evolving character of the campus landscape through time and set forth sound guidelines for landscape treatment and interpretation”

1937 – 2009 – 2016

Planning and Design

Preservation of contributing landscape features / “Protection, preservation and recapture of landscape characterdefining features”. Defines an overall vision for the 2016 campus.

2008 - 2016

2009 - 2016

Design, construction, and technical guidance for near-term campus Planning, Design, protection and rehabilitation Construction Integrated strategies for how to fulfill the 2016 vision for the campus, and which incorporate technical studies, appropriate construction Short-term techniques, and DHS programmatic site needs. Also provides Management technical guidance regarding the metrics for regulatory requirements and specific accreditations (SITES™, LEED™)

Long–term management of contributing landscape features 2016 +

Long–term Management

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CHAPTER II

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Site Assessment & Key Considerations

CHAPTER 2

Site Assessment & Key Considerations

Introduction An understanding of the existing conditions of Saint Elizabeths Campus is necessary for sustainable planning, design, and construction. It is critical that these activities use the existing conditions as an opportunity for guidance of future development, and understand the repercussions of each design decision, as these decisions have a profound impact on the cultural and natural resources of the campus. This chapter introduces these considerations and directs the reader to other available resources.

Cultural and Historical Significance Saint Elizabeths West Campus is a historical, cultural and ecological treasure that embodies the natural and civic spirit of Washington, D.C. The GSA and DHS are designated stewards of this site (as outlined in the 2008 Programmatic Agreement) to ensure that this resource is respected and rehabilitated for present and future generations. The Cultural Landscape Report (CLR), Landscape Preservation Plan (LPP) and the Landscape Management Plan (LMP) set the framework to DEFINITIONS retain, repair, rehabilitate and manage the landscape features on the campus. These documents detail “how rehabilitation treatment The terms rehabilitation and restoration are both common terms in the historic preservation standards guides the protection and appropriate modification of and restoration ecology communities. Within 1 the landscape to suit new uses” . both communities the terms help distinguish The St. Elizabeths West Campus was established as a mental health institution in 1855, reaching its fullest development in the late 1930’s. Historic features remaining from that time include the hospital buildings, residence cottages, curving drives, brick paving, and a variety of incidental landscape structures, set within an equally historic landscape of wide lawns, mature shade trees, and wooded slopes. A historic cemetery, dating from 1856, remains on the wooded slopes below the campus. Landscape changes from the 1940’s onwards have been judged to be non-contributing to the site’s historic integrity.2

an act that literally reproduces elements from a reference point (restoration), from the act of retaining desired features that have integrity, but altering it slightly to perform a modern function (rehabilitation). Although the definitions are similar in both disciplines, please refer to the Society of Ecological Restoration’s definition of rehabilitation when referring to the “living” landscape (soil and vegetation) and the National Park Service’s definition when referring to the “non-living” landscape (hardscape materials, landscape features, etc.) and culturally-defining features.

1 The Secretary of the Interior’s Standards for the Treatment of Historic Properties, Department of Interior Regulations, Standards for Rehabilitation 36 CFR 67 and US Department of the Interior, National Parks Service, updated 2005: Charles A. Birnbaum, with Christine Capella Peters, Secretary of the Interior’s Standards for the Treatment of Historic Properties with Guidelines for the Treatment of Cultural Landscapes, Washington DC, 1996. 2 For more detail, see the Cultural Landscape Report and the Landscape Preservation Plan, Heritage Landscapes (2010)

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The 1937 and 2009 Land Use Plans document which landscape features existed during the campus’s “period of significance” (1937) and which landscape features have been lost over time; see Fig 1, page 199. In addition, the 2016 Plan, described in the Landscape Preservation Plan, is a holistic guide for landscape design at St. Elizabeths West Campus, including preservation and repair of remaining historically significant features and the inclusion of appropriate new features sympathetic to the historic framework. The plans shown in this report reflect the goals of the 2016 Landscape Plan; see Fig 2, page 200 and Chapter III. It is critical that anyone involved in the design and construction of St. Elizabeths West Campus be familiar with any character-defining landscape feature in their project area. These elements include land uses, natural systems, spatial organization and land patterns, views and visual relationships, topography and drainage, vegetation, circulation, landscape structures, constructed water features, and small-scale furnishings and objects. The appropriate treatment to these features is mandated in the Programmatic Agreement (2008) and guidance for this treatment is outlined in the Landscape Preservation Plan and Landscape Management Plan.

Site physiographic Assessment The biophysical characteristics of the campus directly influence and should help guide planning for: •

Plant species selection

Viewsheds in and out of the site

Soil protection and enhancement

Placement of built-elements

Stormwater management

The St. Elizabeths West Campus lies in the Chesapeake Rolling Coastal Plain ecoregion, which is typically underlain with low nutrient, alluvial soils that support Oak-HickoryPine Forests; see Fig 5 Ecoregions and Physiography, page 203 and the stormwater section of this chapter for a full geological description. Within the regional context, this ecoregion is a slightly hilly area between the Piedmont and Middle Atlantic Coastal Plain and this transition is also known as the fall line or zone. The fall line is the steep

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topographic transition between the consolidated rocks of the uplands and the sands, gravels and clays of the coastal plain. Characteristically within the fall line, water in local streams and rivers slows in velocity as it leaves the rolling Piedmont and enters the flat Coastal Plain. These waterways are commonly flanked with marshes and wetlands when left unobstructed by man made elements. Paralleling the Potomac River, below the fall line, bluffs are a geological feature that remains from the historical floodplain, now severed from the natural hydrological processes of this watershed in the D.C. area. The St. Elizabeths West Campus wooded slopes form part of this line of bluffs that encircle central D.C. and are also known as D.C.’s “Green Bowl”; see Fig 5 Ecoregions and Physiography, page 203. The St. Elizabeths West Campus site encompasses a range of physiographic conditions. The upland plateau overlooking the confluence of the Anacostia and Potomac Rivers descends steeply to small-stream lowlands (the former Anacostia river flats). The steep transitional slopes are divided by several ravines; see Fig 6 Site Physiography and Slopes, page 204. Much of the southern and western portions of the campus consists of slopes greater than 25%. This condition paired with the naturally erosive soils, demand careful planning of built elements and high performance erosion and sedimentation control. Each of these topographic conditions has their own unique differences in microclimates, hydrological regimes and plant communities, which should be considered in preserving and restoring site vegetation. Slope aspect is of particular interest for the future landscape along existing and new forest edges, as appropriate species must be chosen based on their tolerance of sun and shade. Attention to these macro and micro physiographic conditions will assist in sustainable planning and design for St. Elizabeths West Campus. See Chapter IV for further discussion.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations The “Green Bowl” Of Washington, D.C. From the National Park Service:

“Washington, D.C. is situated in a topographic bowl. The bottom of the bowl, where the White House and Capitol are located, is in the floodplain of the junction of the Anacostia and Potomac Rivers. Extending out from the floodplain is a series of rising river terraces. These high ridges nearly surround the city (the “bowl”) and are where the earthen Civil War fortifications were strategically built. This fort “circle” could defend the city from any enemy approach. Over the century following the McMillan Plan significant forests have reclaimed some of those ridges and high ground that make up the Civil War Defenses of Washington corridor. Conversely, the city has evolved during that period as well, with a city grid landscape composed of new neighborhoods, commercial strips, apartment complexes, and broad avenues. Interestingly, today the forests and greenspace of the Civil War Defenses of Washington create an important green “curtain” or backdrop that is visible from many vantage points in and approaching the nation’s capital and serve to break-up the otherwise hardened cityscape. Additionally, the natural areas that make up much of the Civil War Defenses of Washington are composed of remnant eastern deciduous forest communities and provide habitat to an impressive array of native plants and wildlife.”

View from St. Elizabeths (1897). Courtesy of Picture History.

St. Elizabeths

St. Elizabeths

Map of “Circle of Forts” Parks Today. Civil War Fort Locations Surrounding Washington D.C. Courtesy of Picture History.

Civil War Fort at Washington D.C. Courtesy of Picture History.

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Site Soil Assessment3 Site soil investigations and soil design are a critical component of any landscape rehabilitation project. Soils are a living system that not only support all biological systems, but also contribute to ecological health. Healthy soil on St. Elizabeths Campus can positively contribute to the landscape by reducing landscape maintenance and improve infiltration for stormwater management. Information about the soil of St. Elizabeths West Campus highlights: •

Potential limitations to development due to soil composition and structure

Appropriate construction laydown areas

Favorable areas for stormwater management

Protection of areas of pristine, natural soil

Prioritize areas for soil remediation and renovation to better support landscape planting

Areas for the rehabilitation of native plant communities and habitats

Many different sources were used to provide a complete picture of the existing conditions of St. Elizabeths West Campus soil [historical aerial photographs, borings by soil scientists and geologists, and existing National Resources Conservation Service data from the Soil Survey Geographic Database (SSURGO)]. Craul Land Scientists have assessed 3 In collaboration with Craul Land Scientists

St. Elizabeths Campus

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much of the existing soil and added detailed information about soil conditions to supplement the NRCS data for the site. In addition, Craul Land Scientists have outlined recommendations for soil protection, mitigation and rehabilitation for St. Elizabeths West Campus. Please see Fig 8 Soil Analysis, page 206 and Chapter III for a summary of these recommendations. The soil of St. Elizabeths varies considerably by location, from pristine, undisturbed soil (NRCS, 2009 and Craul, 2009) to contaminated incinerator waste and debris at depths of up to 12 meters (40 feet) (Applied Environmental, 2005). The native soil of St. Elizabeths West Campus includes silt loam and silty clay loam “loess” over fluviomarine deltic fans and alluvial terrace sediments. Locally, sediments of rounded pebbles and quartz can be found throughout the campus. These types of soil are typically low in pH and are moderately to highly erodible, especially when subjected to disturbance. Dense fragipan (less permeable) soil layers occur frequently at depths around 600 mm (24 inches). The upland plateau includes large areas of native soil that are in excellent condition. These soil areas have high horticultural value, but are also fragile – they compact easily and are vulnerable to inadvertent damage by even light surface traffic. They are also susceptible to erosion. Furthermore, lowering of surface grades may contribute to wetter, less desirable, growing conditions, by bringing plant rooting zones closer to the fragipan. For these reasons, the central spaces, with the highest quality soil, are recommended as Soil Protection Zones; refer to site issues section in Chapter I.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations

Soils of St. Elizabeths Campus

Pristine, Natural Soil. Areas of the campus that have never been developed have pristine, natural soil that should be protected during the construction process, as seen above in the south lawn. In addition, the natural soil can contain rounded pebbles that were historically used on the campus for the aggregate.

Boring data provided by Applied Environmental.

Contaminated Fill. In contrast to the pristine soil, contaminated fill and debris can also be found on the campus, as seen in these pictures above the south ravine. These fill areas can be as deep as 12 meters (40 feet). Native vegetation cannot out compete invasive, exotic vegetation in these areas of severe disturbance without active management.

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Vegetation and Habitat Assessment Context St. Elizabeths Campus represents a crossroads of several environmental conditions. These “confluences” are both physiographic and hydrological and occur at both at the regional and site level. Within the regional context, the site lies at the transition between the Piedmont and Coastal Plain, near the confluence of the Anacostia and Potomac Rivers – each with distinctive plant communities. Within the site, the varied topography, small streams, and groundwater springs create a rich environmental setting, and allow the campus to possibly support a wide variety of vegetation and wildlife. In addition, St. Elizabeths West Campus has the potential to contribute positively to the existing vegetated corridors that parallel both the Anacostia and Potomac Rivers. These corridors provide much needed habitat and green infrastructure for the Anacostia neighborhood and the D.C. metro area; see Fig 12 Regional Context- Vegetation Cover, page 210.

Typical Forest Types on St. Elizabeths Campus as they relate to the soil and hydrological Systems Lowland Forest Communities Riparian Edges + Wetland

Upland Slope Forest Communities Wetlands

Mesic

Dry

Silty Sands

Plastic Clay

Silty Clay

Interlensed clays and sands

Permanent ground water level

note: actual wetland locations on the St. Elizabeths West Campus are not yet confirmed.

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Individual Trees

Cultural Significance

The individual trees on the upper plateau of St. Elizabeths are an invaluable cultural and natural resource. The majority of the trees in landscape units 1 and 2 have been on the site before the 1940’s (CLR, 2009; Bartlett, 2008; Morris Arboretum, 2009) and some are much older, rare species collected from several countries by the second superintendent’s son, Alvah Godding (Dr. William Godding was superintendent from 1877-1899) (CLR, 2009; United States Department of Interior, 1986). Trees of this age and variety, along with the arboretum-like setting, are a unique asset. All precautions should be taken to preserve and maintain them during the construction process. It takes more than a lifetime to produce trees of this size. Removal of these trees could result in changes to the historic views in and out of the site and also change the overall ambience and character of the cultural landscape.

Age

Condition

Rarity/ Unusualness

To preserve this special resource while also accommodating an updated infrastructure and systems for the future users of St. Elizabeths West Campus, information about the individual, specimen trees on the campus has been consolidated and updated within a database.4 Using this database, each tree was assessed based on its significance then mapped; see Fig 14 Indiviudal Tree Assessment, page 212. This information will guide development adjacent to the trees. The purpose of the individual tree assessment is to: •

Delineate structural root zones and tree protection zones in order to protect trees from construction activities5

Locate construction activities away from high value trees

Help design teams make informed decisions about construction methods, construction sequencing and tree protection measures

The individual tree assessment ranks the overall significance of each tree as “excellent, great, good, fair and low”. The ranking for each tree is based on a summation of the following criteria:

4 A synopsis of all the sources of tree data and what kind of data can be found in each source can be found in Appendix C and D. The detailed methodology for the tree assessment is located in Appendix F. 5 Tree locations shown on plans are approximate. The location of each tree and tree protection zones must be verified by a surveyor. Tree Protection Zones were calculated according to Matheny and Clark (1996), with input from the Morris Arboretum.

In addition to individual assessments, the following tree characteristics were flagged to guide the design and construction process: •

Historically significant (Cultural Landscape Report, 2009)

Invasive species (from the VA and MD invasive species list)

Potential disease susceptibility (Morris Arboretum)

Short life expectancy (Morris Arboretum)

Chapters III and IV provide more information on the tree assessment for use in design and construction activities. Refer also to Appendix F for a detailed explanation of the methodology; refer to site issues section in Chapter I.

Native Plant Communities

The current native plant communities are predominantly forest communities of various ages and conditions. In addition to forest, there is a section of woodland (young, open forest) in the south ravine, and a small area of meadow in the adjacent upland. For the purposes of the following discussion, the woodland is included as part of the overall forest system in the assessment of vegetation.

Forest System Overview

At St. Elizabeths West Campus two forest systems overlap, the Northern and Southern Atlantic Coastal Plain Hardwood Forests. St. Elizabeths West Campus exhibits forest associations and alliances within both of these systems. The northern system is typically represented by drier forests with an ericaceous shrub and ground layer on gravelly soils (TNC, 2009). Plant communities associated with the Piedmont are found on the upper plateau and dry slopes, while plant communities on the midslopes and lowlands are more characteristic of the Coastal Plain. Overall, the existing forest of St. Elizabeths West Campus is an eastern deciduous, mixed hardwood forest with few evergreen canopy trees and a low diversity of understory vegetation. The slopes vary from relatively flat to those surpassing a 50% grade. The underlying acidic soils with low fertility and the (remnant) presence of ericaceous shrubs differentiates these communities from the oak-hickory forests common in this region, which have high levels of available nutrients and relatively circumneutral soils. S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations The predominant tree species on the campus are, in alphabetical order: tree-of-heaven (Ailanthus altissima) - an invasive exotic, pignut hickory (Carya glabra), American beech (Fagus grandifolia), ash (Fraxinus sp.), American holly (Ilex opaca), tuliptree (Liriodendron tulipifera), black cherry (Prunus serotina), white oak (Quercus alba) , chestnut oak (Quercus prinus/montana), black locust (Robinia pseudoacacia), and various oaks within the red oak group. In the vicinity of the historic cemetery, there are four primary species in the canopy: tree-of-heaven, black walnut (Juglans nigra), northern red oak (Quercus rubra), and American elm (Ulmus americana).

Forest and Woodland Communities:

Existing Forest Communities

The focus for the ecological rehabilitation plan for St. Elizabeths West Campus is to first fully understand the existing forest communities and then use this understanding as the basis of the plan for future forest communities on the site. Assessment and characterization of the existing communities will contribute to: •

Choice of plant species that will thrive in this setting

Planting plans that reflect the regionally specific vegetation structure, pattern, heterogeneity, function and resilience embedded in natural systems

Design future landscapes in Units 3, 4 and 5 able to cope with disturbance and provide effective ecological services with little long-term human intervention

American Beech – Red and White Oak – Tulip Tree Forest (Mesic Upland Slopes)

American Beech – Chestnut Oak Forest (Dry Upland Slopes)

Box Elder Forest and Green Ash – Black Walnut and American Sycamore Forest (Mesic and Wet Lowland Riparian Edges)7

Red Maple – Blackgum Forest (Upland Slope Wetlands and Lowland Wetlands)8

Successional Woodland (Mesic Upland Slopes)

Please refer to Appendix G for a detailed description of the native forest communities found on the campus and Chapter III for descriptions of the aesthetics and character of these proposed communities.

7 These two communities are combined because their boundaries overlap, are small areas and may represent similar communities with different successional ages. 8 This forest type represents a wetland adapted community. Actual boundaries of delineated wetlands are not yet confirmed for the campus.

Forest communities observed on St. Elizabeths West Campus are summarized below and mapped; see Fig 13 Existing Plant Communities, page 211. Devastation of the ground layer and subcanopy by overpopulation of whitetailed deer (Odocoileus virginianus), along with the degree and repetition of disturbances within the natural areas make it difficult to pair St. Elizabeths West Campus plant communities with documented healthy plant communities defined by local plant community ecologists.6 However, every effort was made to be accurate and the findings were peer reviewed by a professional ecologist, Dr. Roger Latham. The methodology for forest community classification can be found in Appendix H. 6 Ecological communities are defined by the International Classification of Ecological Communities: Terrestrial Vegetation of the United States (Grossman et al. 1998) and the Ecological Systems of the United States: A Working Classification of U.S. Terrestrial Systems (Comer et al. 2003). These classifications are compiled into a searchable database by NatureServe (non-profit conservation organization) and state natural heritage member programs within a web-based information resource called NatureServe Explorer (http://www.natureserve.org).

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Occasional spring wildflowers may be found in the oldest forest sections at the St. Elizabeths West Campus. Although the abundance of wildflowers is likely diminished by heavy deer browing, their populations may rebound following deer control and the installation of the perimeter fence.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Forests of St. Elizabeths Campus

American Beech – Red and White Oak – Tulip Tree Forest (Mesic Upland Slopes)

American Beech - Chestnut Oak Forest (Dry Upland Slopes)

Box Elder Forest and Green Ash – Black Walnut and American Sycamore (Mesic and Wet Lowland Riparian Edges)

Red Maple – Blackgum Forest (Upland Slope Wetlands and Lowland Wetlands)

Successional Woodland (Mesic Upland Slope)

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Forest System’s Current Integrity At St. Elizabeths West Campus the forest as a system is in relatively poor health. It is important to improve forest health in order to ensure its continued viability, improve the aesthetics, and restore ecosystem services, such as erosion control, for the site. This need is discussed at greater length in Chapter III. The first step in stewardship of natural areas is to understand what impacts led to their decline and to identify the severity of the disturbance. This information will help in:

and more importantly by the lack of ground layer vegetation and the prevalence of plant species unpalatable to deer. In a study done by biologists at University of North Carolina at Asheville and the National Park Service at nearby Rock Creek Park in northwest Washington, it was found that excessive deer browsing in a mixed oak-beech forest, much like the forest at St. Elizabeths, resulted in: •

Increases in bare soil, and reduced herbaceous, woody and native plant cover

Reduced density of vegetation less than or equal to 1 meter in height

Increases in invasive species, particularly Oriental bittersweet vine (Celastrus orbiculatus), due to the reduction of plant competition by excessive browsing

Determining the appropriate rehabilitation techniques for each area

Anticipating the level of intervention needed for each part of the campus

Prioritizing rehabilitation

Poor oak regeneration

Identifying and Preparing for emerging disease on the campus

Little to no effect on American beech populations

Drafting a long-term management plan to ensure that rehabilitation efforts are not wasted

The most severe impacts that undermine forest health and impair its ability to provide meaningful ecological services and healthy habitats at St. Elizabeths West Campus are: 1. Lack of biodiversity and pervasiveness of invasive species — Deficient in biodiversity, the forest of St. Elizabeths West Campus would benefit from forest stewardship that actively promotes the regeneration of a wide range of native species and eliminates non-native invasive species in an economically feasible way. Currently, invasive vines are prevalent and smother young seedlings and saplings, contributing to the decline in canopy trees. The lack of spring wildflowers on the forest floor is also an indicator of poor forest health. Increasing native plant diversity and removing invasive species will promote a healthier ecosystem by allowing the forest to support a greater variety of plant and animal species, improving the system’s resiliency when disturbed. Increasing the number and the quality of ecosystem services the natural landscapes can provide. 2. Overpopulation of herbivores, mostly white-tailed deer (Odocoileus virginianus) — From several site visits to St. Elizabeths West Campus over the course of a year, it is obvious that the deer population on the campus is excessive and is beyond the ecological carrying capacity of the site. Evidence of a large deer population can be seen in the abundance of deer pellets found throughout the campus, 16

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In contrast to the West Campus, the East Campus has fewer deer and correspondingly greater oak regeneration and a thicker leaf litter than the West Campus. Oak seedlings are one of deer’s favorite food sources.

Researchers have noted that if the deer population at Rock Creek Park is ignored, the forest will ultimately become almost entirely American beech (Fagus grandifolia) with severely reduced plant diversity (Rossell, Patch and Salmons, 2007). These observations mirror what can be seen at St. Elizabeths West Campus-American Beech predominate and the ground layer is sparse. In addition, when a shrub layer can be found on the campus, it is almost entirely the native shrub, pawpaw (Asimina triloba)- a plant that deer do not typically browse.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations In contrast, the East Campus forest has a considerably smaller deer population and the composition and structure of the forest is different. Although the soils and slopes are similar, conifer species are present (Virginia Pines, Eastern Red Cedars, etc.), young oaks are abundant, American Beech is not nearly as common and the ground layer is healthy and diverse. 3. Past man-made disturbances — The land occupied by St. Elizabeths West Campus has been altered by man on a regular basis since the founding of our nation’s capital and, presumably before by Native Americans. Due to the recent (19th and 20th century) historical importance of the site, these man-made disturbances are well-documented. The range of disturbances on St. Elizabeths West Campus varies in their severity and impact on the site. Factors that govern the severity of a disturbance and the ability of the disturbed area to return to a healthy functioning forest include: •

Frequency of the disturbance

Size and shape of the disturbance

Amount of vegetation removed

Amount of forest floor vegetation, forest floor biota, seed material and soil removed (Oliver and Larson, 1996)

Characteristics of introduced pollutants

Comparisons of the forests on the contaminated ash and debris fill and the returning forest on the abandoned agricultural fields demonstrates the very different disturbances that shaped the site and how plant communities reestablish based on these various conditions. A high frequency of tree falls are likely due to unstable soils in the ash/debris fill area and steep slope areas. These highly manipulated soils have encouraged a woodland that consists mainly of aggressive, invasive non-native species. 4. Signs of emerging disease — Devastating pests and diseases are increasingly becoming a significant concern in the Eastern Deciduous Forest. Specific threats to the St. Elizabeths West Campus forest are the emerald ash borer and bacterial leaf scorch. Of the greatest concern are trees susceptible to these pests and diseases found in places where people frequent, particularly trees in and around the cemetery. Morris Arboretum has echoed this concern, “Some red oaks were exhibiting Bacterial Leaf Scorch symptoms. This is threatening the red oak population in this area. Because of this chronic disease, [the Morris Arboretum arborists] expect that the majority of red oaks will decline and die within an estimated 20 years. There are American elms in this area that are threatened by Dutch Elm Disease. [Also ash trees are threatened by the emerald ash borer]. Anticipate that, if untreated, these tree species will decline and die as well, further decreasing species diversity. The canopy gaps formed by these trees’ demise will probably allow and encourage the establishment of invasive exotic tree species. Native canopy trees should be planted in canopy gaps to help stop invasive exotic trees from getting a foothold (Morris Arboretum, 2009). ” Anticipating these concerns can help with monitoring the overall health of the forest and steward the health, safety and welfare of people on the campus. 5. Erosion and degradation of receiving streams — The negative effects of land clearing and grading, dumping and antiquated and undersized stormwater conveyance systems can be seen in the erosion and slumping of soils, undercutting of surface drainage channels and sedimentation within the drainage channels. This compromise of soil structure has destabilized some trees, particularly near the existing stormwater outfalls from the plateau. In addition, the overpopulation of deer exacerbates erosion and sedimentation problems as they compact the forest floor and browse on plant material that would otherwise support long-term development of a healthy soil system.

Due to the unstable nature and toxicity of the ash fill and debris of the south ravine, trees commonly topple over with greater frequency than in adjacent forest stands. Photo by Tim Craul.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations

Existing Forest Assessment In order to delineate culturally significant, high quality and high functioning forests, each forest stand was assessed; see Fig 15 Forest Assessment, page 213. This assessment identified: •

High quality and ecologically significant areas that need to be protected and/or appropriately mitigated during and after construction of the DHS consolidation

Areas suffering from severe disturbances and overtaken by invasive species

Low quality areas and those areas predominately invasive species, where construction activities can be directed

From current research about the historical campus and forest health, five criteria were chosen to evaluate each vegetation type (Appendix I details the methodology for this assessment). Each vegetation type was described by its environmental characteristics, composition, structure and amount of disturbance. Each was then assigned a weight based on the following criteria. •

Successional status

Cultural Significance

Habitat Value

Overall Health/Integrity

Rarity/Conservation Status.

Each stand was then categorized based on overall significance as excellent, great, good, fair, and low. In addition to the forest assessment calculations, stands that had the following characteristics were flagged to aid in the design and construction process: •

Designated historically significant by the Cultural Landscape Report

A majority of invasive species (VA and MD invasive species list, Appendix J)

A high percentage of large diameter trees

Please refer to Chapters III and IV for more information on the forest assessment for use in design and construction activities.

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Invasive Species Assessment – Proposed Levels of Intervention The removal of invasive exotic plants is an effort that will vary in both intensity and method. In areas where the native plant community is relatively healthy, invasive species may be removed without disrupting the integrity of the plant community. In contrast, areas with high proportions of exotic invasive plants (particularly tree species) and other high levels of disturbance may need to have phased removals, to leave the essential structure of the forest intact. This latter effort is more intensive. The relative level of forest restoration across the site is mapped; see Fig 16 Severity of Disturbances , page 214. •

Minor level of intervention: wooded areas where the native tree canopy is relatively intact. Anticipated invasive plant removals are likely to mimic natural canopy openings (in the case of tree removals) or to focus on understory shrubs, vines and saplings. Subsequent native plant regeneration can be monitored. Naturally occurring native re-establishment may be sufficient. Otherwise, restoration planting can supplement natural regeneration in larger canopy gaps and where exotic re-sprouts outweigh native seedlings.

Moderate level of intervention: includes some forest edges and the security fence corridor, where visibility is critical. The areas of moderate intervention also include new forest (proposed woods per the 2016 plan; Fig 2, page 200), which will require initial maintenance and care during establishment.

Major level of intervention: wooded areas where the tree canopy contains a high proportion of invasive exotic species and/or the woods edge contains many exotic shrubs and vines. Plant removals will need to be paired with replanting. Where the canopy contains many exotic trees, removals must be phased in order to retain the closed canopy structure of the forest.

Intensive level of intervention: wooded areas where invasive plants are prevalent and where the establishment of native forest trees is complicated by soil problems. These are low priority areas for intervention, since a high level of effort is necessary for change. In particular, at the south ravine, soil contamination and compaction likely limits the rooting depth of existing canopy trees, making wind throw of mature trees a more frequent occurrence. These soil issues may


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations restrict the development of mature woods on this site (Appendix B). Restoration work in this area is further complicated by work restrictions related to the bald eagle nest protection zone; see Chapter II for more detail. The continued presence of white-tailed deer outside the security fence, who will continue to browse tree seedlings, is also a consideration.

Site Hydrology Assessment9 History Historically, the Anacostia River was located along the western edge of the campus until a large portion of the river basin was filled during the construction of the Bolling Air Force Base, Anacostia Naval Annex, and the

Approximate Location of St. Elizabeths Late 1700’s historical stream and river network. Much of D.C.’s streams and wetlands were filled and piped in the first half of the 1900’s with dredged material from the Anacostia and Potomac Rivers. Before this, both rivers had a wider floodplain and were commonly flanked with wetlands (Williams, 1977)

I-295 State Highway.

Watersheds The St. Elizabeths Campus lies within the Anacostia River Watershed which is part of the larger Chesapeake Bay Watershed; see Fig 39 Regional Watersheds, page 237. There are seven smaller watersheds on the West Campus. Refer to Chapter III and see Fig 40 Pre-development Watersheds,

page 238 for the locations of Watersheds 1 through 7. Watersheds 1 and 2 are broken into smaller watersheds for runoff computations as required by the regulations of the District Dept. of the Environment (DDOE). The total drainage area of all watersheds associated with the western campus is 99.25 hectares (245 acres), including off site areas. These 7 watersheds are included in the model of the pre-development flows for the western campus. A summary of information for each of these watersheds is described below: Watershed 1 Watershed 1 consists of 7 sub-sheds that total 64.88 hectares (160.3 acres). Approximately 46 acres of Watershed 1 are off site areas. Watershed 1 contains approximately 2/3rds of the total on site area associated with the west campus and is located on the southern section of the site. This watershed drains from east to west through a series of existing on site storm sewers and open channels and ultimately outfalls into an existing 54” pipe that leaves the site and flows into an existing storm drainage system underneath Interstate 295. The higher plateau on the eastern portion of Watershed 1 contains the majority of the existing campus buildings and site infrastructure. The western portion of Watershed 1 includes heavily wooded areas. There is an existing ravine located within Watershed 1 that is severely eroded. This ravine is further addressed in the Ravines section of this chapter. Watershed 2 Watershed 2 consists of 4 sub-watersheds that total 21.29 hectares (52.61 acres). Approximately 1.235 hectares (3.05 acres) are off site drainage areas. Watershed 2 contains approximately 1/4th of the total site area and is located on the northern portion of the site. This watershed drains from east to west through a series of existing on site storm sewers and open channels and ultimately outfalls to an existing storm sewer system located at the northwest corner of the western campus site. Approximately 1/3rd of Watershed 2 is on the plateau. A portion of Building #1 and surrounding roadways drain to the west. Runoff also collects on the plateau and drains to another severely eroded ravine (addressed in the Ravine section of this chapter). The remaining 2/3rds of the watershed consist of open grassed fields to heavily wooded areas on the lower western side of the site.

9 In collaboration with William H. Gordon Associates and GeoConcepts

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Watershed 3 Watershed 3 is 2.09 hectares (5.16 acres). Approximately 0.09 hectares (0.24 acres) is off site drainage area. Watershed 3 is located near the middle of the northern property line and is a relatively small drainage area on the site. This watershed drains from south to north and ultimately outfalls onto the adjoining Barry Farm residential area. Watershed 3 consists of impervious areas (existing roads and driveways) and a portion of Building #18. The area is flat before approaching the north outfall where it drops down a very steep slope that is overgrown with heavy underbrush.

Watershed 7 Watershed 7 is entirely on site with a relatively small drainage area of 0.32 hectares (0.78 acres). It is located in the middle of the property line on the northern side of the site. This watershed drains from south to north and outfalls by sheet flow off site onto the Barry Farms residential area. Watershed 7 contains a small portion of the open field on the plateau. Water from this area sheet flows onto a very steep slope, overgrown with heavy underbrush.

Watershed 4 Watershed 4 is 1.85 hectares (4.56 acres). Approximately 0.23 hectares or 0.58 acres is off site drainage area. Watershed 4 is located in the northeast corner. This watershed drains from south to north and ultimately outfalls at the northeast corner of the site as a concentrated flow that drains to the existing storm sewer system located under Martin Luther King Junior Avenue. Watershed 4 contains the existing greenhouse buildings that are in a state of disrepair, as well as the main security checkpoint entrance to the campus. The area has both impervious surface (roads and parking) as well as open fields.

Up until the 1970s, the campus’s storm sewer was connected to the District’s Combined Sewer System (CSS). Today, CSS’s make-up approximately 1/3rd of the District’s stormwater management system. Pipes of this combined sewer system were designed to carry both stormwater and raw sewage during major storms, often dumping raw sewage directly into the waterways when the storm system overflows. Today on St. Elizabeths Campus, stormwater is managed by a conventional curb and gutter system that conveys stormwater from the plateau, via pipes, to outfall structures on the slopes. This water is part of the Municipal Separate Storm Sewer System or MS4. Water from this system is discharged directly into portions of the Potomac, Anacostia and Rock Creek Watersheds without treatment.

Watershed 5 Watershed 5 is 0.35 hectares (0.86 acres). This is a relatively small watershed located in the southeast corner of the western campus site. Watershed 5 drains from west to east and outfalls into an existing storm sewer system under Martin Luther King Junior Avenue. Site conditions within Watershed 5 consist of an existing inter-campus road that connects the eastern campus through a tunnel that runs below Martin Luther King Junior Avenue. Currently, this tunnel is closed. Watershed 6 Watershed 6 is 9.86 hectares (24.37 acres). The majority of this drainage area is off site with an area of 9.36 hectares (23.12 acres). This watershed is located at the southwest corner of the site and drains from south to north. Watershed 6 ultimately outfalls into an existing storm sewer system located near the southwest corner of the site. Watershed 6 consists mainly of heavily wooded areas, except for a small portion of residential area in Congress Heights.

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Stormwater-Quantity and Quality

Although a separate sewer system for stormwater has been seen as an improvement when compared to combined systems, the discharge from separate systems often contains pollutants that stormwater picks up with it on its way to the sewer system and then our water bodies. These pollutants can be chemical stressors, like pesticides, fertilizers, oil, grease, metals and nutrients; biological stressors, such as pathogens; and physical stressors, such as increased velocity of water flow, temperature changes and sediment loads (Barrios, 2000). Field et al. (1997) have found that separate stormwater systems can contain suspended solid concentrations equal to or greater than those of raw sanitary wastewater. Some of the sources of these stormwater pollutants can be lawns, sport fields, cars, pets, construction sites, power plants, chemicals applied to pavements, failed septic systems, and illegal discharges (Barrios, 2000). Urbanization of land increases these negative effects by increasing impervious surfaces that do not allow water to infiltrate into the ground.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations The Sewersheds of Washington, D.C.

Separate Sewer System, District of Columbia

Stormwater discharge from the St Elizabeth West Campus flows to the Anacostia River. The Anacostia, as an urban river, recieves a high proportion of its water from storm sewers, and is consequently one of the most polluted rivers in the region (citation).

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Under natural conditions, the soil filters and stores water. By increasing the amount of rainfall that is infiltrated, the St Elizabeths West Campus has the potential to help improve water quality in the Anacostia River. At St. Elizabeths, approximately 20-30% of rainfall on the plateau (above elevation 125 meters) infiltrates. This proportion is above the DC average for developed sites (12%) but below its potential, even at the full build out of the DHS Headquarters. Best management practices, such as Low Impact Development strategies which emphasize infiltration and water quality improvement, can further reduce runoff and increase infiltration. Furthermore, recent federal legislation requires an increase in the amount of runoff contained on site; see the Site Environmental Regulatory Zones and Restrictions section at the end of this chapter.

The second and lower zone of groundwater is found in a confined aquifer that consists of intercalated layers of sand in the Arundel Formation (clays of the Potomac Group). Recharge to these sand layers occurs as seepage from the overlying perched water table and, to a limited degree, from precipitation that infiltrates along the lower western slopes where the Arundel Formation meets the ground surface. The steepness and erodibility of these slopes mean that this recharge zone has little potential as part of a site-wide stormwater strategy.

Goundwater Investigation

In order to evaluate the long term dewatering that could occur with new structures built below the perched water table, analysis of the surface hydrology of the site is necessary. This analysis includes delineating the surface drainage divides in order to estimate the amount of precipitation available to recharge the perched water table. The amount of water that recharges the Arundel Formation aquifer from the perched water table aquifer is difficult to quantify. Although pump test data have confirmed a connection between these two aquifers, quantifying the amount of recharge that occurs is extremely difficult because of the unpredictable nature of the connecting fractures. See Appendix Q for the full hydrogeological investigation report by GeoConcepts.

As discussed in GeoConcept’s Hydrogeological Investigation Saint Elizabeths West Campus Redevelopment Appendix Q (2010) and based on their review of the available hydrogeologic reports, there are three zones of groundwater beneath the site. The upper zone consists of a perched water table on top of clay soils of the Potomac Group, within the terrace deposits. These deposits are found throughout the site ; see the hydrogeological investigation report in Appendix Q of this report. The major source of recharge to this perched water table is the precipitation that falls on the site and adjacent areas upgradient. Water here generally flows laterally to emerge as springs on the west- and northfacing slopes at about elevation El. 120 meters to El.130 meters. In addition, this water may provide minor amounts of recharge to the aquifer below through natural fractures and minor continuous sand and ash layers.

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The third zone of groundwater is extremely deep and is found within the “Patuxent Formation.” This aquifer is a significant source of groundwater regionally and feeds the Potomac River. Borings drilled for the GeoConcepts study did not penetrate this lowest aquifer.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations

adapted from Cahill Assoc. Environmental Engineers

Effects of Imperviovs Surfaces

Hydrological System- Natural Condition

Hydrological System- Urban Condition with High Percentage of Impervious Surfaces

Illustration of the difference between the distribution of water under natural conditions and the very different distribution of this water under developed conditions

Changes in the Hydrological System Based on the Percentage of Impervious Coverage (Adopted from Arnold and Gibbons, 1996)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations

Ravines Several steep ravines still exist on the campus today. Many others have been filled in over the years by development. Many of these ravines are fed from a series of natural springs located on the upper slopes of the north, west and southern portions of the campus; see Fig 6 Site Physiography and Slopes, page 204. A large majority of the campus’s site drainage is managed through these ravine systems. The remaining campus ravines have been significantly compromised over the years. Major clearing of vegetation, filling with debris and other hazardous materials, as well as erosion from stormwater dumped into these channels, have all contributed to their degradation. The largest ravine is located on the southern portion of the campus. This ravine drains watershed 1, which is the largest watershed on the Campus and a small portion of the residential development to the south. The first major clearing of this ravine was in the early 1900s when the Baltimore & Ohio Railroad extended a spur to bring coal to the campus’s power plant (US GSA, 2008). This ravine was cleared again in 1963, and again in 1965, during the construction of the Interstate 295. The ravine contains fill which is primarily ash from the power plant, and other materials that reach depths of over forty-five feet in certain locations (Applied Environmental. 2005). The ash deposits pose significant environmental and health concerns due to the amount of contaminants found in the soils. These contaminants include: •

Volatile Organic Compounds (VOCs)

Polynuclear Hydrocarbons (PAHs)

Dioxin and Furon (D/F) cogeners

Heavy Metals

“Previously prepared environmental studies confirmed the presence of total petroleumhydrocarbons (TPH) in the form of diesel range organics (DRO) and gasoline range organics (GRO), lead, and barium at levels that exceeded Washington, DC (DC) action levels, cleanup levels, Groundwater Quality Standards, and/or U.S. Environmental Protection Agency (EPA) risk-based concentration (RBC) in multiple areas of the St. Elizabeths West Campus”.

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The low-point is located at the south-west corner of the campus, in what will be the future pond area of the USCG Building. A significant portion of the campus’s surface runoff drains to this future pond through contaminated ravine soils. Any additional surface runoff from new development could further erode these ravine soils and cause contaminants to leach into the groundwater. If left in place with no amendments, these soils pose severe limitations for stormwater management. The second largest ravine is found at the northern-western end of the campus, north of Sweetgum Lane. This ravine is identified as one of the most historically important forests on the site (Heritage Landscape CLR, 2009). The stream in this ravine appears to be fed from a natural spring and has the characteristics of a ephemeral, first order stream. However, this stream is deeply incised because of the high velocity of runoff discharged into the ravine from several points. The banks of the ravine have been scoured and continue to erode as vegetation and soil are stripped away during the larger storms. The third important ravine is located to the north of Burrough’s Cottage. The ravine has been buried, but is believed to be spring fed and may also have an ephemeral, first order stream that is still active below grade. This stream may be one of the causes of the periodic flooding of the Barry Farm development to the north.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Photos of Plan South Ravive: 1906,1961,1966 and 2008

1908 (Courtesy of GSA)

1961 (Courtesy of Heritage Landscapes)

1966 (Courtesy of Heritage Landscapes)

1988 (Courtesy of Heritage Landscapes) Historic maps and aerial photographs document the history of the south ravine. The woods in the ravine remained largely intact until the 1960s, when the ravine began to be used as a disposal site for incinerator waste. The present-day ravine is a shallow echo of its original topography; although plant cover has returned, the open woodland is highly affected by the nature of the fill soils.

2008 (Courtesy of D.C. Planning Office)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Existing Condition of Sweetgum Lane Ravine The ravine along the north side of Sweetgum Lane, while altered by high stormwater flows, is the best remaining example of the small stream valleys that originally intersected the plateau. The current condition of the stream is illustrated in the photos.

Top of Ravine- Evidence of the instability of the stream channel can be seen in these two photos showing an eroded stream bank. Stream bank erosion can be due to large volumes of stormwater runoff and an insufficient riparian buffer.

Middle of Ravine- Despite the trash that can be found along the stream bed, lovely remnant stone structures, such as this check dam, can be found along the stream channel. These structures should be saved and used as inspiration for future stream channel restoration projects.

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Middle of Ravine- Numerous stormwater pipes empty directly into the stream exacerbating the instability of the channel.

Bottom of Ravine- Here the stream is meandering and dissipating energy from stormwater surges. This is how streams cope with large flows when given sufficient space. These stable flood plains have the potential to be biologically rich places.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations Photos and Plans Burroughs Cottage Ravive: 1906,1961,1966 and 2008

1908 (Courtesy of GSA)

1948 (Courtesy of Heritage Landscapes)

1966 (Courtesy of Heritage Landscapes)

2008 (Courtesy of DC Planning Office)

Historic maps and aerial photographs document the history of the ravine near Burroughs Cottage. The ravine remained part of the campus’s natural landscape until the 1960s, when it was cleared and filled. No visible trace remains today of the original stream valley, although the groundwater flows that fed the stream persist below grade.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations

Site Environmental Regulatory Zones & Restrictions The following areas are subject to environmental regulatory restrictions on new construction at St. Elizabeths West Campus:

Eagle’s Nest Buffer The wooded property south of the campus contains a bald eagle’s nest. The woods on the southern portion of the St. Elizabeths West Campus are part of the regulatory buffer around the nest site. Eagles and their nesting sites are protected under the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act. Under the Acts, disturbance (considered ‘taking’) of eagles and their nest is prohibited. The following general guidelines are summarized from the National Bald Eagle Management Guidelines, which are intended to assist with compliance with the Acts. Specific measures to comply with the Acts are listed below. Any proposed interventions should be reviewed by the US Fish and Wildlife Service (US Fish and Wildlife Service, 2007).

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Maintain a forested (natural landscape) buffer around the nest, with a minimum radius of 660 feet.

Avoid any site activities within the 660 foot buffer, visible from the nest. Small scale, non-visible activities may be permitted outside of the breeding season provided a minimum distance of 330 feet is maintained.

Avoid temporary activities that are noisy and might disturb the eagles during the breeding and nesting season (approximately November through July in the Mid-Atlantic states). Hiking and other non-vehicular recreational activities should remain at least 330 feet away from the nest at this time. Blasting and other very loud events (e.g. fireworks) should only be conducted one half mile or further away from active nests.

Avoid construction activities within the 660 foot buffer during the breeding and nesting season.

Aircraft, such as helicopters, should remain at least 1000 feet away from the nest.

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Stormwater Management Requirements In 1972, Congress passed the Federal Water Pollution Control Act, commonly referred to as the Clean Water Act (CWA). The primary objective of this act was to restore and maintain the chemical, physical, and biological integrity of the nation’s waters by preventing point and nonpoint pollution sources. It also provided assistance to publicly owned treatment facilities to improve waste and stormwater treatment, in order to preserve the integrity of the nation’s wetlands. In accordance with this law the majority of the combined sewer systems (CSS) throughout the District, including the branch that serviced the St.Elizabeths Campus, were separated to reduce the amount of pollutants that entered rivers and streams. While the separation of these combined systems was an improvement, it did little to reduce the direct discharge of pollutants into waterways. In 1987 the CWA was updated in order to require the Environmental Protection Agency (EPA) to establish a program to address stormwater discharges. In response, the EPA initiated NPDES stormwater permit application regulations, which required a NPDES permit for (1) a discharge associated with industrial activity; (2) a discharge from a large or medium municipal storm sewer system; or (3) a discharge determined to violate water quality standards. This permitting process now requires the engineers to implement stormwater management practices that address pollutants at their source and improve stormwater collection, conveyance and treatment before it is discharged from a site. During the next two decades “Green Design” and “Sustainability” increasingly influenced building design and site planning. Many nearby states (New Jersey, Maryland and Pennsylvania) have developed manuals for alternative stormwater management practices to encourage infiltration and treatment of water through solutions modeled on natural systems. In addition, an increased awareness of the consequences of global climate change and the need for protection of natural resources has lead to legislation, which emphasizes reduced energy use and conservation of water resources. In October 2009, President Obama signed Executive Order 13414 (EO 13414). The focus of this order is primarily significant reductions in energy consumption and greenhouse gas emissions. However, this EO also strengthens the requirements for the protection and conservation of water resources. In addition to the EO, the


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Site Assessment & Key Considerations EPA recently issued Section 438 of the Energy Independence and Security Act in December of 2009. This act imposes strict requirements for the stormwater management of all Federal projects. This government legislation, in concert with the District Department of the Environment’s (DDOE) stringent guidelines for water quantity and quality, and the LEED™ and SITES™ criteria, has made stormwater management a priority for the sustainable design and development of St. Elizabeths Campus. Section 438 Section 438 of the Energy Independence and Security Act is “stormwater runoff requirements for federal development projects. The sponsor of any development or redevelopment project involving a Federal facility with a footprint that exceeds 5,000 square feet shall use site planning, design, construction, and maintenance strategies for the property to maintain or restore, to the maximum extent technically feasible, the pre-development hydrology of the property with regard to the temperature, rate, volume, and duration of flow.” (House Bill 6, 2009) In order to achieve Section 438 requirements the 95thpercentile rainfall event must be prevented from running off the site. In the D.C. area this rainfall is 1.7”over a 24 hour period. This depth is weighted over the entire development footprint by accounting for both impervious and pervious surfaces. DDOE The District Department of the Environment (DDOE) developed a design manual that presents the minimum standard criteria to be used by design engineers and planners for the planning, design, and construction of Best Management Practices (BMP’s) in order to comply with the District of Columbia Storm Water Management Regulations (District of Columbia Municipal Regulations (DCMR) Title 21, Chapter 5). This Stormwater Management Guidebook requires both water quantity and quality controls.

The post-development peak discharge rates of both the 2-yr and 15-yr storm events must be reduced to at or below the 2-yr and 15-yr pre-development peak discharge rates. The above ground stormwater management facilities should be designed to safely pass the 100-yr storm events. (District of Columbia, Department of Health, Storm Water Management Guidebook, 2003)

Contaminated Soils There have been extensive studies done on the contaminated soils on the St. Elizabeths West Campus. The majority of these soils exist in the southern and western portions of the Campus; primarily, in the south ravine area. These soils consist of ash and other solid wastes that are suspected to have come from the on-site waste incinerator and coal-fired power plant. Contaminants identified include volatile organic compounds, polynuclear hydrocarbons, elevated levels of various metals and dioxin and furan congeners. These soils pose extreme limitations on stormwater management and landscape restoration efforts, and raise health concerns for portions of the Campus.

Wetlands Probable wetland areas at the St. Elizableths West Campus, including ephemeral 1st order stream corridors and seeps along the south and west facing slopes, are indicated in the Master Plan (Jones, Lang and LaSalle and SmithGroup, 2008). Preliminary delineations for the westlands on site are currently being reviewd by the Army Corps of Engineers.

The water quality requirements are determined by applying 0.5” of runoff depth to all impervious areas on the proposed site. To improve quality x amount of water volume must be treated by filters, natural percolation, detention, or extended detention or an equivalent processwithin 48 hours and then released. (District of Columbia, Department of Health, Storm Water Management Guidebook, 2003)

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CHAPTER 3

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g

CHAPTER 3 Design Guidance

Introduction Chapter III presents the overall approach and integrated design concepts for the schematic and early design development phases of the St. Elizabeths West Campus landscape. It is intended to provide the coordination necessary to give cohesiveness to the landscape character, restore the campus to an ecologically healthy and culturally rich place, streamline construction activities and prevent waste. Although the details of the strategies summarized here have, inevitably, evolved throughout the writing process, and will continue to be updated as the construction process proceeds, the goal of this Chapter is to summarize key design concepts. These concepts remain consistent in intent, and also provide sufficient flexibility to deal with unforeseen changes over time. Please refer to the Site Issues section of Chapter I for items that will require further investigative studies. Chapter III is organized by subject- Historic Landscape, Soil Management, Vegetation, Hardscape Materials and Stormwater Management. These sections consist of: •

Introduction

Approach

Design Guidance

Design Guidance Terms The following sections of Chapter III will highlight significant natural and historic features and the integrated effort needed to preserve and protect, relocate, rehabilitate, replace or introduce these features within the Landscape Integration Plan framework. These terms are defined as follows: •

Preservation and Protection – first do no harm. Then, take measures to prevent damage during the construction period. Preservation and protection means stewardship aimed at protecting and stabilizing existing site features.

Relocation – moving or salvage of valuable items in the landscape to save them from damage or destruction.

Rehabilitation – making possible contemporary cultural uses by rehabilitating site features, while maintaining their historical and ecological integrity. In the case of soil, vegetation and stormwater management, rehabilitation means reestablishment of ecosystem functions to support an overall healthy system where it has been adversely impacted. For site circulation, rehabilitation means reestablishment of the historic hardscape to allow for modern use.

Replacement – the introduction of new landscape features similar to those that existed in the period of significance.

Introduction – new compatible elements added to the historic landscape.

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Project Limits There are numerous projects being implemented concurrently on the St. Elizabeths Campus that are in varying stages of planning and construction documentation. Construction of these projects will be achieved in phases through 2016 (See Chapter IV for detailed phasing plans). As a large portion of the campus will be disrupted, the site and landscape projects can be implemented in conjunction with the building, utility, and security projects. Coordination between landscape protection and rehabilitation, security requirements, utility tunnel construction, site access and on-site movement during construction, is essential. Fig 3 Project Area Plan, page 201 represents the most current plan for proposed projects. This diagram is intended to help consultants understand key opportunities and design coordination issues in relation to the rest of the campus. In addition it gives the GSA project managers a clear view of the proposed projects’ construction limits to help facilitate the DHS consolidation of St. Elizabeths West Campus.

Historic Landscape The Landscape Preservation Plan (Heritage Landscapes, 2010) provides a description of the historic landscape and guidance on how to preserve its integrity while being adapted to new use.

Approach

The Landscape Preservation Plan (LPP) emphasizes the need to “accommodate future uses within a philosophy of respect for what has survived from the period of significance” (Heritage Landscapes, 2010). The LPP divides interventions in the campus landscape into three categories: 1. Preservation of remaining historically significant landscape features. Surviving historic features within the campus landscape include identified paving and walls, mature trees, sections of the forested landscape, and a number of other built features. These features are identified and described in the LPP. Guidance for their stabilization and repair is provided in both the LPP and in this report. Each feature should be respected and repaired as part of the individual design project. 2. Adaptive rehabilitation of existing historically significant features to new uses. This category includes roads and walkways that must accommodate higher levels or additional types of use. It also includes basic stewardship of existing natural areas, which require

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rehabilitation in order to accommodate security needs while maintaining their historic and ecological integrity. Guidance for adaptive rehabilitation of historic features is provided in this report. 3. Introduction of new, compatible elements into the historic landscape. This category includes ADA access ramps, bus shelters, security facilities, recreational amenities, and water features (both decorative and for stormwater management). In addition, design teams may chose to reintroduce lost features that previously existed in the historic landscape. In general, new features should be appropriately designed to be similar, but not identical to their historic counterparts. Ideally, new features may be designed to help renew the historic character of the campus by removing incompatible modern elements and making use of historic precedents (Heritage Landscapes, 2009). This chapter provides guidance on the conceptual design of anticipated new features.

Design Guidance 2016 Landscape Plan Fig 2, page 200 , by Heritage Landscapes illustrates the proposed campus land use, cover types, circulation, facility expansion, and areas for vegetation restoration. This plan, and its relationship to the existing (2009) and historic (1937) campus are described in detail in the Landscape Preservation Plan. The overall intent is to: •

Illustrate the integration of intact character-defining features into the design of the renewed campus

Reintroduce historic features (trees, forest, paving, minor landscape features) which are appropriate to the contemporary use and function of the campus

Remove contemporary additions (excess paving) which detract from the historic integrity of the campus and are not necessary to the contemporary facilities

Individual landscape elements are discussed in the following sections under Soil Management, Stormwater Management, Vegetation, Circulation, and Hardscape Improvements. Historic features are also discussed in the Cultural Landscape Report, the Landscape Preservation Plan, and the (long term) Landscape Management Plan.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Site Soil Assessment1 Soil is the foundation of the visible landscape. Protection and management of existing soil is key to a healthy, functioning campus landscape. Healthy soils are essential to vigorous plants, important for effective stormwater management, and reduce landscape maintenance. Conversely, soil damaged through compaction, contamination, or improper mixing will have, in all likelihood, higher plant mortality and contribute to increased maintenance efforts over the long term. Protection and management of soil also benefits trees. The majority of campus trees are mature, irreplaceable (in a reasonable time-frame) and historically significant; their continued well-being relies on healthy soil. Access to healthy soil areas must be severely restricted during the construction phase. This section highlights design considerations related to the protection and rehabilitation of soil within the campus landscape. Opportunities for soil salvage as a resource for campus landscape repair are also summarized. Construction staging directions, outline specifications and schematic construction details are found in Chapter IV. Please refer to the Site Issues section of Chapter I for items that require further investigative studies.

Approach Protect high quality soil from construction activity, especially pristine natural soil, to the greatest extent possible. Areas of natural soil with large historic trees should be rigorously protected. These efforts will save time, money and limit the chance of planting failure. Appropriate soil design and soil enhancement is important for success on all landscape projects. Soils are living systems that are the foundation of the other biological systems on 1 In collaboration with Craul Land Scientists

the campus. Poor soil produces poor plant health; therefore, soil health should be the first and foremost consideration in planting. Steep slopes should not be developed to minimize potential for erosion. The steep slopes of the St. Elizabeths campus are highly erodible. To avoid future problems these slopes should be avoided during construction.

Design Guidance Soil Preservation and Protection

Craul Land Scientists, in collaboration with Andropogon Associates, have assessed the current soil on St. Elizabeths West Campus. The soils are grouped according to their horticultural value, ability to support construction activities, vulnerability, and need for protection; see Fig 8 Soil Analysis, page 206 and Table 1. page 33 Soil Assessment .2 Avoid planning activities for lawn areas which would contribute to soil compaction. The soil may be affected through routine, frequent use, or by single intensive events. The soil will be most vulnerable when it is wet, typically in spring or after heavy rainfall. Soil requiring high, moderately high and moderate levels of protection must be barricaded during construction to prevent unauthorized construction staging (see Fig 4 Site Protection Zones and Construction Areas, page 202 ). Site protection fencing will also provide a high level of protection for the historic trees within the same area. See section: Preservation and Protection for Individual Trees, for more information on trees and design. See also Chapter IV for construction related guidance. Highly erosive soil and steep slopes should be avoided during construction unless absolutely required. Fencing and associated infrastructure should be made to fit the landscape and be designed to minimize soil erosion and protect existing historic trees. 2 Please refer to Appendix B for full soil report by Craul Land Scientists.

Table 1. Soil Assessment STAGING AREA

LARGE SCALE PLANTING

EROSION CONCERNS

LEVEL OF PROTECTION

CANDIDATE FOR REMEDIATION

Pristine Natural Soils

Poor

Excellent

Moderate

High

Limited

Mixed Natural Soils

Poor

Fair

Moderate

Moderate - High

Moderate

Compacted Natural Soils

Fair

Fair

High

Moderate

Moderate

Compacted Fill

Good

Poor

High

Low

Extensive

Gravelly Sandy Loam Fill

Excellent

Poor

Moderate

Low

Replace / Extensive

Contaminated Fill

Poor

Poor

High

Low

Replace / Cover

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Soil Salvage

Good quality soil, salvaged from proposed construction areas, is a potential resource for landscape repair. Locations that could benefit from ‘transplanted’ soils include areas of non-historic paving slated for eventual removal, areas of severely damaged soil where remediation is not feasible and construction staging areas. Potential areas for soil salvage and replacement are indicated in Fig 9 Soil Salvage Opportunities, page 207 . The specifics of sequencing and coordination between salvage and placement locations will need to be resolved by the architectural teams on a project by project basis. Transplanting Soil “Blocks” In areas with high quality natural soil and desirable vegetation, such as open historic lawns (away from trees) or wooded areas where native species predominate, the entire ground layer (approximately 18” of soil that includes herbaceous plants, soil microbes and topsoil) can be dug up and transplanted to a new, similar location. The advantage of this technique is that the transplanted soil is biologically intact. Soil salvage is only worthwhile where the natural soil and ground layer are in good condition. Soil sods may be re-set in place to restore a temporary disturbance (e.g. utility corridor) or moved to a new location on-site as part of a re-vegetation strategy.

Forest soil salvage: removal of “soil sods,” from site of origin onto wooden pallets. The pallets are then moved to the new planting site.

Soil Rehabilitation

Some existing soils on the campus have been affected by past construction activities. These effects include compaction, mixing (deep soil horizons brought to the surface), and intermingling with imported fill or other debris. Where severe compaction currently limits potential root development, the area is recommended for construction staging. Repair of the compaction will be necessary after construction and prior to replanting. Soil rehabilitation should be included in the construction scope for site projects. See Chapter IV for more detail on soil repair and construction sequencing.

Soil Replacement

The most feasible and cost-effective option for some campus sites may be to replace or cap the existing soil. These sites include areas where planting will replace existing paving, areas where severe compaction makes native soil rehabilitation impractical, fill areas at new building construction, contaminated soil and areas where the desired soil performance needs cannot be met by the existing native soil (e.g. infiltration areas, high-performance sports fields). In these cases, replacement soil may be obtained from either on-site salvaged soil or by imported engineered soil, as appropriate. Sand-based engineered soil have the potential advantage of being less fragile and therefore more easily worked than many existing native soil on campus. 34

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Forest soil salvage: removal of “soil sods,” from site of origin onto wooden pallets. The pallets are then moved to the new planting site.


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Vegetation The design strategies for vegetation integrate several considerations: •

Preservation of historic integrity

Protection of beneficial natural resources

Improvement to stormwater management

Accommodation for security needs

Rehabilitation of existing woods

Approach Preserve and rehabilitate historical landscape types. Historically at St. Elizabeth’s West Campus, the landscape types ranged from ornamental courtyards to natural forests. The Cultural Landscape Report (CLR) and Landscape Preservation Plan (LPP) describe the historic conditions, proportions and types of vegetation cover and the locations of pre-1937 trees and forest. The guidance of the CLR and LPP emphasize the preservation of pre1937 trees and woods and the re-establishment of both the historic tree canopy within the open lawns and the historic woods at former ravines; see Fig 1 Comparison Plan, page 199 . In addition to woods, the plans provided in the LPP propose meadow establishment in areas where there once were meadows or agricultural fields. This report uses this guidance as a baseline for its recommendations, while also seeking to accommodate the new uses of the campus. Support the ecological integrity and health of significant trees, meadows and woods; in order to maintain their long-term presence on the site. Specimen trees within the historic hospital grounds require advance design consideration and protection to ensure their long term viability on the campus. These considerations must include soil-based measures to maintain the favorable rooting conditions essential for tree health. Also, in an urban setting such as this, meadows, woodlands and forests require some degree of management to ensure their optimal health and maximize the ecosystem services they provide over the long term.3 Without active management of the urban meadow or forest , heavy deer browse of seedling trees and/ or the competitive pressures of aggressive exotic

plants will inhibit the reproduction of native plants and result in the decline of the native landscapes into a tangle of weedy exotics. Ironically, active intervention is necessary for native landscapes to remain as such in urban areas. Maintain the visibility and open structure typical of managed forests, to enhance safety and aesthetics. At St. Elizabeths West Campus several interests converge – historical, ecological and security. Open forests, thinned of shrubs and saplings, have been a component of the historical landscape at St. Elizabeths and of the earlier forests managed by Native Americans. Forests with open understories are preferred for security needs. Conversely, forests that have high proportions of invasive shrubs and vines appear tangled and ‘messy’. The forests of the St. Elizabeths West Campus are characterized by a large proportion of invasive, exotic plant species, particularly at the forest edges and areas that have suffered severe disturbance. Removal of exotic shrubs, vines and saplings would not only benefit the health of the present-day forest, but also fulfill the needs of the future users of DHS and those responsible for preserving the historical integrity of the campus. Protection of existing trees and forest should be holistic and be part of all design and construction strategies. The character and integrity of the tree collection within the therapeutic grounds (the plateau) and the integrity of the surrounding forest are each considered as a whole. Soil and hydrological considerations are integrated into the planting recommendations. The integration of individual tree and forest rehabilitation into site protection and stabilization during the construction process is critical. This approach will leave the campus with an improved historic and ecological integrity at the close of construction. It is always preferable to avoid damage or loss of mature trees through sustainable design. However, where impacts are unavoidable, their relocation, rehabilitation, or replacement should be considered and may be of benefit to the campus.

3 Ecosystem services provided by forests include cleaning the air and water; stormwater management; prevention of erosion and sedimentation; provision of habitat for wildlife; climate regulation and cultural benefits.

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No Management

Invasive, Exotic Vegetation

Active Management

Native Vegetation

Above: Urban forests, like those at St. Elizabeths Campus, require active management to prevent invasive species from overtaking the forest after a disturbance, as shown in the two illustrations above.

Left: At St. Elizabeth West Campus, the forest on the left side of the photograph is mostly native. However, on the right, invasive species are proliferating in an area that was disturbed approximately 40 years ago. Sites overtaken with invasive species will not return quickly to a healthy forest without active management. Tree development is slow on the altered soil, and the canopy layer has yet to re-establish. Exotic species have invaded the open woodland setting.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Visibility in the Forest

Design Guidance Proposed Landscape Types In this section, campus plant communities are discussed in the following hierarchy: (see Table 2. Summary Of Proposed Landscape Types., page 38 )

Photo 1

Landscape Type

Natural Plant Community Structure

Target Natural Plant Community (primary)

Target Natural Plant Community (secondary)

Landscape type is the broadest category for all proposed vegetation on the campus. The proposed landscapes are divided into ornamental and natural cover types. These vegetation types are shown in the proposed landscape types plan; see Fig 17 Proposed Landscape Types, page 215 . Each cover type has an implied degree of human intervention. They range from areas that are completely planted to areas that are organized largely by natural processes – from ornamental gardens and courtyards to forest and meadow.

Photo 2

Natural Plant Community Structure and Target Natural Plant Communities (primary and secondary) provide more detailed information for each of these landscape types, but are mostly applicable to the rehabilitation of natural landscapes (forest, woodland and meadow). Detailed information is based on existing plant communities, plant species common to the area, levels of current and proposed disturbance, microclimate, physiography, hydrology, soil, historical goals, and location (whether the area lies within a forest interior or edge).

Photo 3 Historically, forests on the St Elizabeth’s Campus had a thinned understory (Photo 1). Managed woods are typically open and attractive, while woods dominated by non-natives are tangled and dense. Photos 2 & 3 show Philadelphia’s Carpenters Woods at different locations with a person standing at the same distance from the camera. Photo 2 shows a managed forest with native plants, which drop their leaves early in the fall and leaf out late in the spring, increasing seasonal visibility within the woods. Photo 3 shows an unmanaged portion of the same forest, on the same day. Note the decreased visibility and denser shrub growth of the non-native plants. Non-native plants often leaf out earlier in the spring, and hold their leaves later in the fall compared to native species.

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Table 2. Summary Of Proposed Landscape Types. LEVEL

I

II

III

IV

V

CATEGORY

Proposed Landscape Types (Fig 17, page 215)

PURPOSE Provides the overall structure of the vegetation type and identifies the degrees of management proposed. The following examples are ordered as a continuum of intervention from ornamental to natural.

EXAMPLES ORNAMENTAL: • Historic Gardens and Courtyards • Historic Tree Collection* • Historic Cemetery • Historic Cemetery Woodland NATURAL: • Meadow • Woodland** • Forest

Severity of Disturbances (Fig 16, page 214)

Gives insight for landscape project managers and maintenance supervisors and identifies the amount of effort required to fulfill historical, ecological and security goals in each area from 2009-2016.

• • • •

Minor Moderate Major Intensive

Proposed Natural Plant Community Structure (Fig 19, page 217)

Indicates the horizontal and vertical arrangement of plant species and the planting densities required for each area. Based on threats of nearby invasive species, aesthetic considerations and sun exposure.

• • •

Forest Edge Forest Interior Young Woodland, Future Forest

• • •

American Beech - Chestnut Oak Forest (Dry Upland Slope) American Beech - Mixed Oak - Tulip Tree Forest (Mesic Upland Slope) Black Gum - Sweetbay Forest (Upland Slope Wetlands) Box Elder - Eastern Poplar Woodland (Wet-Mesic, Mesic Upland Slope) Green Ash-Black Walnut and Sycamore Forest (Wet Lowland Slopes and Riparian Edges) Red Maple - Black Gum Forest (Lowland Wetlands and Upland Slope Wetlands) Meadow

• • • •

South and west-facing edges North and east-facing edges Forest interior where exotic species predominate Forest interior where native species predominate

Target Natural Plant Communities (primary) (Fig 20, page 218)

Target Natural Plant Communities (secondary) (Fig 21, page 219)

References the plant species proposed for each area. Each natural plant community is associated with large scale environmental conditions, such as physiography and hydrology, as noted. These suggestions are starting points for planting during the construction phases. Over the long term, these plant communities may shift in response to environmental conditions and require new strategies. Helps choose plant species from the primary plant community lists, most appropriate for small scale differences in environmental, ecological or cultural conditions.

• • • •

* Refer to the Landscape Preservation Plan for the Historic Tree and Garden Collection plant groups. ** The term “woodland” is used to refer to a successional forest, with a relatively open tree canopy (approximately 20-60%), remaining for a long period of time based on anticipated, persistent or severe disturbances, such as contaminated soil or regular mowing schedules. Forests, by contrast, are defined as having canopy cover of over 60% (Grossman et al., 1998)

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Historic Gardens and Courtyards Desired Design Character The arboretum-style planting of specimen trees within the lawn on the plateau and in the historic cemetery is unique and historically significant. The Landscape Preservation Plan (LPP) discusses their historical significance in depth and should be referred to for more detailed information. Overall, these areas are informal plantings of large, specimen trees that shade the lawn below. The historic campus had many more shade trees than exist at present; consequently many additional trees should be planted in locations where they existed historically. The species are very diverse. The LPP documents these specific locations and lists recommended species. Also of significance are remaining tree allées, such as the double line of white oaks east of the Center Building, and the trees lining both sides of Cedar Drive between Burroughs Cottage and Gatehouse 1. New planting should consider options for repairing the allées.

The garden courtyard at the south of the Center Building included two water features. The multi-tiered cascade fountain remains in the landscape today. (Photo R-STEgarden 1898.jpg. Courtesy Heritage Landscapes and Library of Congress)

Within the cemetery, a similar arboretum-style landscape exists. However, within the lawn is a blanket of spring wildflowers (mostly Claytonia virginica- spring beauty), which bloom in April-May. These spring wildflowers are dormant in summer, and consequently are no longer visible by July.

The historic oak allée at east of the Center Building remains within the present-day campus

Former sitting area at Burroughs Cottage

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Individual Trees – Preservation and Protection4 Tree Protection Zones Many existing campus trees are protected from construction activity as part of the larger Site Protection strategy. Tree protection zones within construction areas have additional restrictions related to excavation and trenching. The tree protection zone includes both the structural and biological roots, which extend well beyond the drip line (canopy extent) of the tree. The outer portion of the tree protection zone represents the biological root zone – the area where the feeder roots are concentrated. The majority of these roots lie within the top 18 inches of the soil and collect water and nutrients for the tree. The inner portion of the tree protection zone also represents the critical area where the structural (supporting) roots are concentrated (Morris Arboretum, Appendix M). Both biological and structural root zones are important to tree preservation and long term health. Since the majority of a tree’s roots lie close to the ground surface, all construction activities should avoid the entire tree protection zone. Refer to Chapter IV for details. When preserving trees within construction sites – especially significant trees such as those at the St Elizabeths West Campus – it is important to define the tree protection zone as realistically as possible. This report uses a published method (Matheny and Clark, 1996) to calculate the approximate tree protection zones for each tree. This methodology bases its calculations on tree size, age class, and the tolerance of the species to construction disturbance. The appropriate tree protection zones are shown in Fig 22 Tree Protection Zones- Overall, page 220 , and tabulated for individual trees in Appendix X. See Chapter IV for specific details regarding the tree protection zones and construction activities. 4 In collaboration with Jason Lubar, ISA Board Certified Master Arborist, Morris Arboretum

Tree Root Zone

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Examples of individual trees within the Historic Tree Collection (top, middle) and Historic Cemetery (bottom)


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Root Zone Investigations Mapping a tree’s actual root system can be used to ‘individualize’ a tree’s Tree Protection Zone, to help determine low-impact utility routes and other architectural elements, such as footings, requiring excavation. This investigation may be useful where available space outside of the tree’s root zone is limited and where the tree is a high quality, historic specimen. In mapping an individual tree’s roots, an air spade temporarily exposes the root system. There is some evidence that air spade work damages soil biology, so sensitive trees such as oaks, beech and pines may benefit from remedial applications of compost teas or mycorrhizal fungi following air spading. This investigative work needs to be requested, bid, and approved during the early phases of a project if it is to be effective in informing design decisions. Such work must be done under the supervision of a qualified arborist. Pre-stressing Trees Trees which are “prepared” in advance for the stresses of nearby construction have a higher probability of successful outcomes in the long term. Typical horticultural activities include chemical treatments to promote root development and reduce drought stress, advance root pruning (where excavation is anticipated), fertilizing, and other measures aimed at promoting overall tree health. These methods of preparing trees should be begun at least one growing season in advance of construction, and must be requested, scoped, bid, and approved during the early design phases of the architectural/engineering project. While this investment requires forethought, these measures can save the mature trees on campus. Grade Beams, Piers, and Cantilevered Foundation Walls Small building additions and other site structures should consider specialized foundation designs as an alternative to continuous footings. Point footings, grade beams, and cantilevers have a limited extent of excavation and may reduce the impact to the root systems of adjacent trees.

Root Zone Protection from Compaction Due to Construction Traffic When construction activities cannot avoid movement over tree roots, measures must be taken to limit the effects of compaction to the existing soil. Access routes that cross through Tree Protection Zones must protect the soil from compaction, contamination, and other disturbances. In the design stage, consider potential access limitations and strategize appropriate architectural details. Avoid designs that require large equipment where space is limited near existing trees that are to be retained. Traffic lanes must first be directed to areas where sidewalks or roads will be placed. In other areas, a matting system should be used to protect the soil from compaction. Canopy Pruning for Construction Access Architectural construction and renovation near existing trees may require advance canopy pruning to minimize canopy damage and allow vertical access to the façade. Consider potential access limitations and design architectural details that protect trees and their root systems from damage. Grading Design within Tree Protection Zones Site and architectural design should preserve existing grades within the Tree Protection Zones to the extent possible, in order to minimize the risks to existing trees. The exception to this direction is pavement design, which may be built slightly above existing grade to minimize excavation within the root zone (see Chapter IV). Where grade changes are unavoidable, slight increases in elevation (up to 12 inches fill) are preferable since tree roots may survive a small increase in soil cover. Cut conditions, which sever roots, are undesirable. Fill should never be designed around tree trunks since the added soil will rot the bark. Tree wells or low retaining walls will maintain air circulation around the trunk.

Grade Beam Alternative For Foundation Walls

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Walkway Design within Tree Protection Zones Walkways and other paving have the potential to cause damage to tree roots through both the excavation and subsequent compaction for the sub-base construction. Impacts to adjacent trees can be reduced with the following measures: •

Where possible, avoid high-load bearing (vehicular) pavements, which have thicker sub-bases, within tree protection zones.

Where possible, use low-load bearing (pedestrian) pavements

Design shallow pavement sections, to minimize excavation

Design for finish grades slightly above existing grade to ensure minimal to no excavation

Retain existing roots in the aggregate base course

Curve walkway alignments to avoid trunk flare and minimize future pavement upheaval

Consider flexible pavements with supporting geotextiles and minimal compaction

Irrigation Design within Tree Protection Zones Irrigation should only be considered when it is absolutely necessary, and should be a temporary measure to alleviate a site specific problem. These situations include:

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When existing trees may be extremely close to construction activities and under a lot of stress

Trees that are within close proximity to new construction, where deep excavation is proposed

If there is an unusual condition of prolonged drought during the construction process

Where irrigation is necessary within tree protection zones, the following must be considered in the design:

Do not drastically alter the existing hydrological conditions of the area

Consider using harvested rainwater for irrigation, however make sure it is properly filtered

Spray from irrigation heads should not be directed to the above-ground parts of the trees; Drip irrigation is preferred

Plot the least disruptive route for the irrigation lines outside of the tree protection zones

Consider irrigation software that is capable of sensing a n d r o p o g o n a s s o c i at e s lt d .

the current climatic conditions or has a convenient manual override system to prevent unnecessary irrigation after rain. Examples include soil moisture sensors, digital rain gauges, and remote access irrigation software which can be viewed and controlled from any computer with internet access

Individual Trees – Relocation Existing Tree Relocation It may be appropriate to consider transplanting large trees in selected cases where historically significant, mature trees would be severely impacted by construction. Mature trees require lead time, in advance of construction, to prepare the tree for the move. Advance planning should be coordinated with an experienced contractor specializing in large tree moving. Considerations include: •

Proposed site characteristics: the slope, aspect, and soil conditions of the new site should match the original site as closely as possible

Preparation time: preparation work will include root pruning, canopy pruning, chemical treatments and, time permitting, other measures to improve tree health. This preparation is most effective if done throughout the growing season prior to the move (i.e. 9 to 14 months in advance), however shorter times may be feasible

Time of year: moving large trees during the dormant season (approximately November to February) is most desirable. Transplanting at other times of year may be feasible, depending on the specific situation and with sufficient post planting care.

Species type and individual tree health: a professional arborist with experience in large tree moving can provide an opinion of survivability and transplant feasibility for the tree in question

Utility clearances: existing underground utilities may conflict with proposed root ball excavation. In addition, sufficient overhead clearance will need to be confirmed along the moving route

Post-transplanting care: should be contracted for at least 2 years following the move. Care will need to include irrigation and monitoring


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Individual Trees – Rehabilitation Consider Emerging Disease Risk when Choosing Plant Species Over the years, several efforts have been made to document tree health, take proactive measures to support the health of the trees , and treat disease and pest infestations on the campus. Within Appendices C and D is a detailed, consolidated summary of each tree that has been documented, its health history and any actions taken to support its optimal health. In the future, this database should be continuously updated for use by designers and arborists. Careful attention to tree health is especially important in places where people will frequently be passing through or visiting. Ultimately, trees should need little help in surviving, but during construction activities it is possible that undesirable environmental conditions can stress trees and make them more susceptible to pests and diseases. The goal of the Landscape Integration Plan is to minimize such conditions through the construction process, but there are also proactive measures that can be considered before the construction process to prevent declines in tree health. The GSA has a policy of proactively managing their urban forest to protect noteworthy trees from emerging diseases and insects. The following tree species are subject to severe insects/diseases and, at present, may require annual inspections and/or treatments in order to support their long-term health: •

American elm – Dutch elm disease. Without annual preventative treatment, American elms have an uncertain lifespan

Ash – emerald ash borer. The emerald ash borer has been found in southern Maryland within the past 6 years (Prince George’s County, 2003 and 2006; Charles County, 2008). While Maryland Department of Natural Resources and the Maryland Department of Agriculture have implemented an eradication and monitoring plan (Maryland Department of Agriculture, 2009), containment of pests is a difficult task and the long-term outlook for ash species is uncertain. Annual preventative treatments are available for individual trees.

Red oak group (e.g. red oak, pin oak, scarlet oak), and to a lesser extent sycamores, maples, elms – bacterial leaf scorch (BLS). This chronic disease causes infected trees to chronically decline and die. While there is neither prevention nor cure for BLS, watering during

drought periods may reduce disease symptoms and help extend infected trees’ lifespan. Prompt removal of infected wood may help slow the progress of the disease; however, this management technique has not been scientifically validated. Trees at risk for BLS, especially the red oak group, should be protected from environmental stresses such as drought, salt, and root damage. Successful tree protection during design and construction is important because it can help extend the life span of trees susceptible to BLS. The design teams should not necessarily ‘write off’ elms, ashes, oaks, or other tree species within the St Elizabeths West Campus due to potential disease concerns. Individual trees receiving preventative treatment should be confirmed with the GSA. Soil Structure Remediation Tree health is largely dependent on soil health and the health of the biota that live within the soil, such as mycorrhizae. Ideally, soil around trees should consist of 5% organic matter, 50% mineral particles and 25% pore space (Neely and Watson, 1998) and have a texture that is 20% clay, 40% sand and 40% silt (Fazio, 2000). Compaction and other construction damage within tree protection zones can alter soil characteristics in such a way that destroys roots, decreases air space within the soil, and kills soil biota. Although trees can tolerate certain levels of disturbance, trees which have experienced past soil compaction or have necessary construction or equipment access within their Tree Protection Zone may require soil remediation following construction. Soil remediation should be appropriately budgeted and scoped within the construction documents and specifications to improve soil conditions for trees. Refer to Chapter IV for specific recommendations for soil structure remediation. Protection from Drought Stress during Recovery from Construction Damage As trees recover from past disturbance, such as construction, it is helpful to protect them from further environmental stress. Proactive irrigation is beneficial during drought periods, since the recovering tree will have fewer reserves to combat subsequent stresses. Irrigation needs to be carefully balanced so as not to change the hydrology of the soil. An alternative effective treatment is a tree growth regulator such as paclobutrazol, a foliar spray that reduces water loss from the leaves and promotes root growth. Paclobutrazol has been shown to benefit tree recovery following construction (Rainbow Tree Care, 2010). S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Soil Chemistry Remediation (fertilizing and other health boosts) Fertilizing, via top dressing with compost or compost teas, can benefit the tree and soil biota. For certain species, it may be beneficial to inoculate tree roots with mycorrhizae. Pruning Pruning of dead wood within the canopy can be both a health and safety benefit. A certified arborist should determine if pruning is necessary and be present for the work.

Individual Trees – Replacement The Landscape Preservation Plan requires that the historic tree canopy within the plateau be restored. This requirement translates to the replanting of approximately 400 trees within the open lawns surrounding the historic buildings. In addition, it is the recommendation of this report that very large, healthy trees also be replaced in kind, consistent with the requirements of the Urban Forestry Administration’s regulations for large trees (Special Trees) within the District of Columbia (Urban Forestry Administration 2002). This is the requirement for private development within the District of Columbia, and it would be appropriate to hold this historic site to at least the same standard. The LPP recommends the following standards for tree planting: •

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The extensive tree canopy that historically shaded the lawns of the hospital grounds shall be restored through extensive replanting. The LPP provides an analysis of historic tree locations and appropriate sites and species for replanting. See Chapter IV for recommended phasing.

Consider replacing in-kind any mature trees larger than 17.5 inches dbh (55 inches circumference), which are also of high quality (>2 on the Individual Tree Assessment). The replacement trees should have an aggregate diameter equal to the diameter of the original tree.

The minimum sapling size for new trees is 2 inches caliper, unless the desired species is available only at smaller planting sizes (e.g. hickories and some oaks).

Trees species shall preferably be straight species (not a cloned cultivar), unless specific cultivars offer better disease resistance or regional hardiness. Selected trees shall not include invasive species, as documented in the Maryland and Virginia Department of Natural Resources lists (Maryland Department of Agriculture, 2009). Note that Acer platanoides (Norway Maple),

a n d r o p o g o n a s s o c i at e s lt d .

Ailanthus altissima (Tree of Heaven), and Morus sp. (Mulberry) are not permitted to be planted within the District of Columbia. •

Trees shall be field grown and balled-and-burlapped. If wire baskets are used, they must be removed during planting. Avoid the use of container-grown stock, since research indicates that trees grown in containers have higher frequencies of delayed failure from girdling roots and other root defects. Trees shall conform to the Urban Tree Foundation’s standards for quality nursery stock (Urban Tree Foundation, 2010).

Historic Cemetery and Cemetery Woodland Desired Design Character The Cemetery is a naturalistic, park-like setting with mature canopy trees over a diverse lawn and low-growing forest wildflowers. The Cemetery is framed by a zone of managed forest which is thinned for greater visibility and neatness. See the Cultural Landscape Report and Landscape Preservation Plan for more detail about the cemetery’s history and culturally significant features. Preservation and Protection The spring wildflowers are a key part of the unique character of this place. Lawn maintenance and invasive species management should be adapted to avoid unintentional damage to the wildflowers. Important considerations are potential wildflower loss from herbicides, fertilizers, and too-frequent mowing; consider sustainable, organic techniques, and scheduling work for the wildflower dormancy period (typically July through February). Additional tree protection measures are discussed in the Individual Trees section.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Rehabilitation Since many of the tree species in the cemetery and adjacent woods are vulnerable to disease, pro-active establishment of young saplings would be appropriate in order to maintain the overall integrity of the tree canopy, and the defining pattern of mature forest canopy trees in lawn and wildflowers. Replacement Within the limits of disturbance for adjacent construction (i.e. US Coast Guard Building and the West Access Road), it is recommended to re-establish forest cover to the greatest extent possible, to maintain the character and quality of the wooded setting for the Cemetery.

Landscape character at the Historic Cemetery and Cemetery Woodland

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Natural Landscapes – Meadows, Woodlands and Forest Desired Design Character – Meadows Meadow is proposed where historically relevant (Landscape Preservation Plan), and in limited areas to protect steep slopes from erosion by absorbing stormwater runoff (see stormwater section). In this historic setting, meadows should be short and discretely ornamental. The following are additional recommendations for meadow character: •

Uniform in texture and height, preferably between 300 and 600mm (12 and 24 inches) high

Framed by neat edges, such as well-maintained lawn, grass path, or well-defined forest edge

Dominated by fine-textured grasses, including both cool- and warm-season native grasses. Warm season grasses are green in summer, provide fall color and upright winter structure; cool season grasses green up in early spring when other plants are still dormant. Landscape character of meadows within arboreta Drifts of wildflowers (optional) for seasonal bloom and pastoral settings

Desired Design Character – Forest and Woodlands

In general, the woods at the St. Elizabeths West Campus are not intended to be aesthetically enhanced as a horticultural display typical of a botanical garden. However, some aesthetic aspects of the woods are important to the new campus uses and the historic integrity of the wooded slopes. These include: •

Attractive Forest Edges The edges of the woods are the most visible from the ornamental landscapes on the upland plateau and from the access roads. These forest edges are critically important to the perception of a well-ordered and well-kept landscape. Removal of vines, invasive shrubs, and dead wood are important at the visible edges.

Visibility Sight lines into the woods are desirable from a security standpoint. Strategic thinning for visibility can be combined with invasive plant management.

Neat, Legible Forest Structure Minimize the extent of ‘tangled’ woods, caused by excessive vines and low quality plant communities dominated by invasive exotic species. Stewardship measures aimed at supporting a baseline level of forest health will also increase the attractiveness of the woods.

The woods immediately around the Cemetery have their own specific aesthetics and management. These are discussed in the section “Historic Cemetery and Cemetery Woodland” of this chapter.

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a n d r o p o g o n a s s o c i at e s lt d .


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Forest and Woodland – Preservation and Protection Forest Protection Zones Existing forested areas that have an assessment calculation of fair or better and those that fall at the fringe of any construction activity and its associated limit of disturbance should be protected, much like the individual trees on the plateau; see Fig 15 Forest Assessment, page 213 and Chapter IV for a discussion of limits of disturbance. For forest edges, the forest protection zone should be delineated as the horizontal distance equal to the height of principal trees at the forest edge. Principal trees are those that are native species and greater than 25mm (1 inch) dbh. For construction activities within the forest, it is preferable to limit construction activities to the smallest area possible. Place protection fencing at the edge of this area to prevent workers and machinery from damaging the forest. Forest Trees within the Limit of Disturbance It is preferable to work around stands of forest trees that fall within the limits of disturbance if they pose no hazard to people or the construction process. When wooded stands within the limit of disturbance must be removed, trees can be “coppiced” or cut back to approximately 100mm (4 inches) above the ground. If the remaining stumps do not create a safety hazard for construction workers, the benefits of leaving the stump include the possibility of the tree re-sprouting and the benefits of soil stabilization that root systems offer. Invasive plant species within the limits of disturbance should be removed with the most effective methods5. Large woody material that is removed can be chipped and composted for reuse throughout the campus; small woody material that may re-root should be disposed of appropriately off-site.

Proposed landscape character of forests at St. Elizabeths

An attractive and healthly forest edge.

5 Refer to the USDA’s Nonnative Invasion Plants of Southern Forests by John Miller for identification and removal recommendations of invasive exotic plants found in Appendix 5.10.

Neat, legible forest structure. (Courtesy Virginia Natural Heritage Program)

Visibility. (Courtesy Virginia Natural Heritage Program)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Minimize Root and Soil Damage within Construction Zones and Limits of Disturbance Utilize the Soil Preservation and Protection guidelines for high quality soil in the Soil Management section for soil recommendations through the forest.

Meadow, Woodlands and Forest – Rehabilitation

As discussed in the introduction to this section, the goal of meadow, woodland and forest rehabilitation is to maintain a healthy, stable, and attractive native landscape, appropriate to the historic character of the campus. This landscape must also support security needs with increased visibility. Rehabilitation at St. Elizabeths aims to achieve initial success within a relatively short time frame. The specific rehabilitation strategies presented in this Chapter include recommendations for: •

How to prioritize where rehabilitation should take place- Prioritization for Rehabilitation

How to execute a rehabilitation effort- Critical Steps for the Rehabilitation Process

Priorities for Rehabilitation It is recommended that rehabilitation of the campus meadows, woodlands and forests be prioritized in the following order; see Fig 18 Natural Plant Community Management Priority, page 216 : Priority 1 • Areas of new disturbance. Since resources are being allocated to these new areas of disturbance, it is recommended that they also be the first priority for rehabilitation. Priority 2 • Healthiest and historica lly significant existing forest. High quality woods with low levels of invasives (historic woods) and any new/small infestations of fast-spreading exotics (i.e. areas with greatest potential damage without management). It is most effective to put in a small amount of effort to support a forest which is already relatively healthy. The remaining high quality areas, including the most historically significant forest, are therefore a high priority for early restoration. •

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Highly visible meadows and forest edges. Since healthy managed woods typically have better internal visibility than woods with many exotic vine and shrub species, the restoration of forested and meadow areas closest to the perimeter fence and plateau edge should also be a a n d r o p o g o n a s s o c i at e s lt d .

high priority. Early removal of aesthetically undesirable (“messy”) invasive plants in these areas would also foster a good impression of the campus forest in general. Priority 3 • Moderate quality forest • Meadows Priority 4 • Areas dominated by invasive plants and those that are both low quality and have low visibility. Lowest priority is given to places with more severe infestations of invasive species, where the integrity of native plant community is already compromised. Since restoring heavily damaged (low quality) areas requires considerable time and resources with potentially less significant results, these areas are considered a low priority. Critical Steps for the Rehabilitation Process It is essential that short-term management of the St. Elizabeths forests follow a critical path for rehabilitation in order to avoid wasted efforts. The first step in forest rehabilitation should address the factors that currently suppress the regeneration of native trees and contribute to decline of the existing native forest, before attempting to rehabilitate the native tree canopy. These current influences include excessive deer browse of native vegetation, and the presence of invasive exotic plant species. Therefore, the critical path for forest rehabilitation is first, deer population management; second, invasive species management; and third, re-establishment of native species. Step 1: Deer Population Management – Ensure that deer will not destroy newly planted areas and continue to degrade the existing forest. The construction of the security fence will provide effective exclusion of new deer to the majority of the campus. However, there will be areas on the campus that are exterior to the security fence that will continue to be accessible to deer, but will require new planting. It is also possible that deer may still be present within the security fence after construction. Deer should be effectively controlled to ensure that new planting efforts will not be wasted. For those areas inside of the security fence, it is suggested that the deer population be removed or reduced to not more than 10-12 deer per square mile (about one deer for the St. Elizabeths West Campus woods) ensuring that few, if any, remain inside after the final construction phases of the fence. Removal techniques can include either driving them out or culling the herd. Close monitoring of the forest


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance inside the security fence will help decide whether or not the deer population is at a level that is destructive to planting efforts. Performance criteria indicative of an appropriate deer population level are the renewed presence of tree seedlings and woodland wildflowers on the forest floor. These should be visible as early as the first growing season following reduction of the deer herd. Annual review of the deer population and the remediation of any impacts should be a part of the forest management strategy. In the forested areas outside of the security fence, it is recommended that the planting strategies consider the following: •

Large caliper trees with the majority of the branches above 1800 mm (6 feet)

Trunk protection, such as rebar stakes

No or limited use of seedlings or whips

No or limited use of shrub and herbaceous plant material, except for those proven to not be attractive to deer, such as Asimina triloba (paw-paw), Lindera benzoin (spice bush) and some ferns. Note that with a high deer population, even unpalatable material, including the bark of trees, will be eaten.

Deer repellents

Temporary fencing for rehabilitation areas- Fencing that is used for limits of disturbance can be left and moved to the planting extents after construction to serve as deer protection until newly planted vegetation has reached a “deer-proof” size.

Step 2: Invasive Species Management – Remove invasive species prior to planting and in critical areas to support overall forest health, fulfill security needs and to ensure that new planting is not smothered my aggressive, invasive plants. As summarized in the introduction to this section, both the historic appearance of the forest and the efficiency of security procedures would benefit from a strategic thinning of the understory layers of the existing woods. Many of the non-native invasive plants, which contribute to the suppression of native tree seedlings, occur as shrubs, vines, and saplings in the forest understory and are often more visually dense, leaf out earlier in the spring and hold their leaves later in the fall when compared to native vines and shrubs. By removing the exotic shrubs, vines and saplings, the West Campus woods will become more open at eye level and will also become healthier because native saplings

(the next generation of forest canopy trees) will be able to establish. While the initial effort of removing invasive species is relatively high, on-going thinning and invasive plant removal should be much more modest. However, it is also important to balance desired visibility within the forest with an appropriate level of native saplings and shrub regeneration. Some native sapling growth is necessary for the long-term renewal of the forest canopy. Some shrub layer is critical for wildlife habitat, especially small mammals, forest birds, and beneficial insects. Step 3: Re-establishment of Native Species-Choose appropriate plants and short term management strategies based on surrounding existing native plant communities, environmental conditions, visibility, historical context and security needs. When choosing plants and/ or short-term management strategies for rehabilitation, consider the following: Landscape Type – First, acknowledge which landscape type the project area falls in: forest, woodland, meadow, historic cemetery woodland or historic cemetery; see Fig 17 Proposed Landscape Types, page 215 ). Plant Community Structure and Pattern – The second consideration for choosing plant species or management strategies for rehabilitation is the arrangement, type and density of plant material that is appropriate for the rehabilitation effort. Security needs, sun exposure, existing plant material, visibility and historical character are all considerations for plant material that may be appropriate in a project area. The Proposed Natural Plant Community Structure (Fig 19, page 217) indicates specific conditions, or ‘end points’ which would be the result of forest rehabilitation. These forest conditions include: • Forest/Woodland Edge, including the security fence corridor. Forest edges on the campus are important for campus security and for overall forest health. These areas must provide both openness at the eye level, but also be planted and maintained in such a way as to prevent ideal conditions for non-native invasive plants. Consequently, it is suggested that forest edges: 1. Receive a higher level of stewardship to maintain openness in the forest 2. Be replanted with native plants that “seal the edge” to prevent the invasion of dense, nonnative plants 3. Be carefully monitored to ensure that native tree regeneration is occurring S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance • Forest/Woodland Interior: These areas should receive a minimal level of ongoing thinning to control invasive plants and maintain visibility. Because they are further from security perimeters, saplings and shrubs may regenerate here with little intervention. • Young Woodland – Future Forest: This should be a “two layer” forest, consisting of closely spaced, even-aged young trees above, and a shade-tolerant meadow below. The tree canopy shall be closed, with only occasional sunny gaps; the shady conditions and dense trees will help limit shrub growth. Over time, this pattern will develop a more layered vertical structure, as the maturing trees thin out. • Historic Cemetery: The cemetery is currently maintained as a mature tree grove with a ground layer of lawn and spring wildflowers. Saplings are minimal and the shrub layer has been removed. This character should be maintained by regular thinning of the understory and infrequent mowing schedules, which are delayed to allow the spring wildflowers to flower. • Historic Cemetery Woods: The woods immediately surrounding the cemetery should be managed to limit the density of understory vegetation. Currently, a mature tree canopy shades the tallest saplings (subcanopy) and herbaceous ground layer. Young saplings should be thinned to provide greater visibility and the shrub layer should be minimal. •

The third consideration for rehabilitation of the natural landscape types is choosing the appropriate species for the project area. Based on the surrounding existing plant communities and environmental conditions, Fig 20 Target Natural Plant Communities- Primary, page 218 indicates what plant communities are appropriate for a given location and indicate the dominate species. A plant list for these communities can also be found in Appendix O.

There are six primary native forest communities proposed for St Elizabeths West Campus—four upland and two lowland – and meadow. The proposed forest types presently occur on or near the site. Although the forest communities are currently fragmented and highly disturbed, they have the potential to be made more distinct through long-term management. The target plant communities include:

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American Beech – Chestnut Oak Forest – xeric upland slope forest

American Beech – Red and White Oak - Tulip Tree Forest- mesic upland slope forest

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Black Gum – Sweetbay Forest (“Magnolia Bog”)- hydric upland slope wetland forest

Box Elder – Eastern Poplar Woodland- mesic upland slope forest

Green Ash – Black Walnut and Sycamore Forest- hydric lowland riparian edge floodplain forest

Red Maple – Blackgum Forest- hydric lowland and wetland forest

Meadow

The upland plant communities are proposed for the bluffs at the fringe of the plateau and midslope areas. These upland plant communities are differentiated as dry, mesic or wet, based on microhydrology. The wetlands are very small freshwater wetlands caused by groundwater seeping out of the hillsides. The lowland plant communities are proposed for the ravines and the former floodplain of the Anacostia River, where surface water accumulates continuously, seasonally or only after rain storms. Floodplain communities are proposed for areas adjacent to surface water channels that flood occasionally. Wetland plant communities are proposed where surface or groundwater causes saturated soil. Meadows are proposed in areas once used for agricultural purposes or in areas that historically were meadows or infrequently mowed lawn. These areas should need very little maintenance (irrigation, fertilizers, herbicides, mowing regime) and offer more seasonal interest when compared to conventional turf. However, short-term maintenance plans should include removal of invasive species. If managed properly in the establishment period, invasive species management in the long term should be minimal. Mowing schedules for meadows should take into consideration growing periods for native versus non-native species, to use mowing as a method for invasive species suppression, and native ground-nesting birds nesting seasons. In addition, these areas can be graded and designed to support stormwater management on the campus by retaining and infiltrating stormwater. The Target Natural Plant Communities Plan (secondary) Finally, when considering specific plants within a Primary Target Natural Plant Community, topographic aspect and prevalence of invasive exotic species should help guide what specific species to include and short-term management strategies for rehabilitation. These are mapped in Fig 21 Target Natural Plant Communities- Secondary, page 219 and a plant list can be found in Appendix O.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Meadow Establishment

There are different methods for establishing meadows. Two viable options are presented here: Method #1: Managed Conversion of Existing Lawn. This method is viable where native soil is relatively intact, and where field observations suggest that natural regeneration of native meadow plants will occur from the existing seed bank. The method is based on a simplified technique developed for homeowners by the New Jersey Audubon (Matsuoka, Tama et al. 2009). The conversion has the advantage of exposing no bare soil and maintaining ‘meadow’ plants from the start. It may be summarized as follows: •

A change in mowing timing and height, which favors the growth of native warm-season grasses over turf grasses

Monitoring the native meadow species that emerge;

Prompt removal of weed species and invasive exotics before they can spread

Plant specific wildflowers or grasses, if desired, into the meadow as plugs

Method#2: Meadow Establishment by Seeding or Planting. This method is best for bare soil areas (e.g. regraded areas following construction), areas where the soil is sufficiently disturbed to require amendment in order to be suitable for meadows, or where very specific plant species are desired. The advantage of this method is that it allows the designer to plant a specific species mix with a relatively high degree of control. The downside is that the existing plant cover must be killed first, and the early meadow appears very sparse. Proper site preparation and weed control are especially important in this establishment method.

Young Woodland – Future Forest The forest establishment areas are proposed where forest cover has been lost on the west-facing slopes and ravines. Some of the forest was lost in the mid-twentieth century following the end of the period of historic significance. Other losses will occur as a consequence of construction activity. With a greater efficiency in architectural design or construction operations and a reduction of the limit of disturbance, some of this reforestation may be unnecessary. Proposed forest locations are shown on the 2016 Plan; see Fig 2 2016 Landscape Plan, page 200 . Aesthetic Character of Forests and Woodlands.

Young Woodland: initial tree planting and lawn conversion to short meadow

Forest and Woodland Replacement Stabilization of New Forest Edges Where construction disturbance removes portions of existing woods, the newly exposed forest edge should be replanted with fast-growing native trees and shrubs. The existing trees on the newly exposed woods edge may be vulnerable to wind throw, since their root systems are adapted to the conditions of an interior forest, and may not provide adequate support in high winds. Supplemental replanting along the new forest edge helps shelter existing forest plants from the “edge effects” of increased wind and sunlight. These plants will also occupy space and shade areas that may otherwise be prime target areas for invasive species. Invasive species should be controlled in the planted area for at least 5 years.

Young Woodland: developing (pole-stage) woodland with a shady meadow on the ground below

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Site Circulation, Access, & Hardscape Improvements This section provides guidance to GSA Project Managers and architectural/engineering design teams as they develop the circulation and hardscape improvements within their individual project areas. The intent is to provide an overview of the opportunities and constraints on the site, in the context of the historic campus, and as envisioned in the Landscape Preservation Plan. It also includes updated information on site circulation, hardscape and materials from the construction documentation underway for the Security Perimeter and Gate Houses, Phase 1b Adaptive Reuse, and West Access Road projects. For this reason, the LIP mapping may have updates not shown in the overall concept plans presented in the LPP

Approach Coordination of a coherent circulation plan with improvements to the existing hardscape is essential to the successful functioning of the St. Elizabeths campus. The following approach was developed to maintain and enhance the historic character while allowing new uses and integrating operational and sustainability goals. Key elements of this approach include:

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Provide guidance for GSA Project Managers and architectural/engineering design teams regarding overall circulation, landscape elements and hardscape materials to be incorporated within the various design and construction projects for the West Campus.

Design circulation to reinforce the priorities of preservation, restoration, rehabilitation and reconstruction, established in the Landscape Preservation Plan and the Landscape Management Plan, both during and after construction.

Provide safe vehicular and pedestrian movement including ADA access during all phases of construction. Provide service and delivery routes that do not impair natural or historical resources, especially for employees and VIPs during the phases where occupancy and construction overlap.

Keep the landscape protection zones (as delineated in the Landscape Preservation Plan) free from circulation routes, construction staging, and parking areas.

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Design Guidance The Master Plan, Cultural Landscape Report, and Landscape Preservation Plan document the historic circulation patterns and create the organizing principles for new patterns for future users. As the master plan is implemented, additional considerations that address the day to day functioning of the site will need to be included in the planning and design of the site and individual projects. New roadways must be integrated into old alignments, new uses must be accommodated and new codes must be met, as the site becomes a secure 21st century campus.

Vehicular Circulation Roadways The roadway network on the Campus is designed to provide construction, delivery, fire and emergency access during the construction phases as well as support the campus after full build out in 2016. The 2016 Circulation, Elements & Objects plan included in the Landscape Preservation Plan (LPP) outlines the proposed road network. It shows the rehabilitation of the existing historic road network as well as the construction of new roads to support the campus. The Master Plan and the LPP emphasize a pedestrian oriented campus. All passenger vehicles are directed to the parking decks at the periphery of the Campus. The only exceptions to this requirement are VIP vehicles that will be allowed on campus after a VIP screening at Gate 1. In addition to the VIP vehicles, fire, emergency, and delivery service vehicles carrying perishable goods will also be allowed on campus. The perishable deliveries will be screened at the large truck facility located at Gate 6. All other deliveries will be routed to the Remote Delivery Facility (RDF) at the north western corner; see Fig 27 Campus Roadways, page 225 . Historic Road Rehabilitation The major roadways of the historic campus will be rehabilitated. The historic alignments and widths will be restored and roadways will use historic materials. The minor roadways that were historically constructed with crushed aggregate and concrete will be reconstructed with pervious or bituminous asphalt. All rehabilitated historic road sections should be constructed to modern standards. Some delivery service, fire, and emergency vehicles are currently unable to successfully navigate turns along the historic roadway network; the turning radii at these locations (e.g. the road east of the Letter Buildings) will be enlarged. Historic circulation routes should be widened in accordance with the guidelines provided by the Landscape Preservation Plan and should use the construction techniques illustrated


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance in Chapter IV of this report. Historic alignments should remain visible within the roadway paving and should retain the historic materials. Any additional road segments should be complimentary in treatment, but sufficiently different so as not to be confused with the historic roadway. See the Design Character and Hardscape Materials Framework section for character and material guidelines for historic roadway rehabilitation. New Road Construction New roadways without historical precedent will be constructed to modern standards. All roadway construction will be carefully coordinated with the construction phasing. Uniformity of materials and techniques must be monitored throughout the construction process. A new two-way service road will be constructed south and west of Sweetgum Lane to improve delivery and service to the historic plateau from gate 6. An additional one way fire access road will be built south of the Phase 3 buildings. This fire road will also be the security trail at this location. The roadways within Phase 3 will be developed based on the overall guidance provided in

the Landscape Preservation Plan (Chapter IV, Circulation) and in this report. Temporary Road Construction Temporary roadways may be necessary during the several different construction phases. These roadways should be constructed of materials salvaged from demolition on campus that can be recycled and incorporated into the base course of the final roadway alignments. These temporary roadways should be located where they will cause minimum disturbance to the cultural and natural landscape. Temporary Parking Temporary parking will be provided for contractors during the various construction phases. This parking should not be located within the landscape protection zones. Rather, it should only be placed in areas where soil quality is low ; see Fig 8 Soil Analysis, page 206 ; and where future construction and/or demolition will take place. These parking areas will evolve along with the

Historic Road. Concrete roads and a drop-off loop are evident in this historic-period image looking north across Unit 2. (Photo R-STE-DC0137SE0P017.jpg Courtesy Heritage Landscapes and National Archives II)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance corresponding construction phases. Appropriate and safe pedestrian circulation to and from these areas will be necessary. Where possible, pedestrians should move along existing pavements. However, during some phases new walkways may need to be constructed. Construction of these new walkways should follow the guidelines in this chapter. Permanent Parking Permanent employee and visitor parking will be provided primarily in three new parking structures. When employees are using the campus while it is still under construction, small temporary parking areas may be constructed at designated locations on the plateau. These locations should be coordinated with the GSA and the Proposed Laydown plan (see Fig 53, page 251)

Passenger (VIP) Vehicle Movement VIPs will be allowed vehicular access within the campus. Signage should delineate zones where this access is permitted. Some VIP parking spaces may be provided at each building.

Delivery Service Network The delivery service network has been placed on the periphery of the site and will have minimal impact on the primary visual zones, as defined by the Landscape Preservation Plan. It is also recommended that GSA/DHS schedule deliveries to miss peak pedestrian traffic times on the campus. Some routes will be appropriate for vehicles of all approved sizes, while some will have limitations due to historic design parameters, which must be preserved. The turning radii of some of the historic roads will need to be modified to allow access for WB-50/ WB-15m vehicles. As the design and layout of the Phase 3 buildings is underway, the Landscape Integration Plan only indicates areas for potential access. Actual delivery zones and building entrances will be shown by the design team. Perishable goods should only be delivered to locations providing food service. Dry goods may need to be delivered to every building on campus. Dry goods delivery will be at the RDF. After screening, dry goods will be allowed on campus, but only in the approved small delivery vehicles. Perishable goods allowed access to the campus will be screened at the large vehicle screening facility at Gate 6.

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Delivery Zones / Lay-By Areas/ Service Vehicle Parking/ Vehicle Storage Delivery vehicles may require special access points at each building. The delivery access points should be located away from the most public side of the buildings, to ensure minimum impact to the historic character of the Campus. Deliveries can be accommodated at the loading docks, or at specially designated service doors. However, design of the service access points should allow other vehicles to pass and provide adequate space for these vehicles. Lay-bys as well as delivery parking spaces are indicated on Fig 28 Delivery Service Network, page 226 . Campus delivery vehicles will be parked in the RDF.

Maintenance/ Waste Removal Network Maintenance vehicles will require access to all portions of the site once the campus is fully operational. Many of the buildings on campus may require periodic servicing including, but not limited to, paper shredding, trash pickup, building maintenance, and recycling services. Larger vehicles will be given designated routes. Smaller vehicles will have greater flexibility; see Fig 29 Maintenance/ Waste Removal, page 227 for location of major and minor routes. Maintenance zones will be designated and parking spaces provided. Because the design and layout of the Phase 3 buildings is underway, the Landscape Integration Plan only indicates areas for potential access. Actual maintenance and waste removal routes will be shown on the documents of the design team. Additional consideration must also be given to a strategy for campus waste management and for the composting of wet waste, to comply with the recommendations of the Sustainability Working Group. Dumpster Location and Sizing The intention is to have as few dumpsters as possible. New dumpsters may be required at certain locations, such as dining facilities. Where feasible, a single dumpster can service a group of buildings. Where possible, they should be located outside of the historic viewsheds. The United Facilities Criteria (UFC 4-010-01) Standard for Trash Containers requires 10 meter offsets from new and existing buildings. If these criteria cannot be met, alternatives include placing the trash containers in hardened enclosures or securing them from unauthorized placement of objects. Screen walls, which are compatible with the historic character, should be considered for screening the dumpster areas; see Fig 29 Maintenance/ Waste Removal, page 227 for proposed dumpster locations. Dumpster sizing will be dependent on building use and population.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Maintenance Equipment Storage Maintenance equipment will be stored in the designated zones highlighted in Fig 29 Maintenance/ Waste Removal, page 227 . In addition to serving other functions, Building 49 will house the campus maintenance office.

Emergency and Fire Network Emergency and fire access will be required throughout the campus. The existing circulation network will need to be enhanced and expanded in certain locations to meet current code requirements. The United Facilities Criteria (UFC 3-600-01) requires that every building greater than 465 meters (5,000 square feet), or more than two stories high, must have at least one means of all-weather ground access to allow emergency vehicles unimpeded access to the building. All-weather ground access must be paved. It must begin at the road, and terminate no farther than 10 meters (33 feet) from the building. Buildings do not need to have access on all sides, but every portion should be reachable by fire hose, within 150 feet of the access road. Any dead end fire access roads in excess of 150 feet must be provided with a turnaround provision such as a hammerhead or culde-sac. For further reference see the International Fire Code (IFC). Fig 30 Emergency/ FIre Network, page 228 indicates a general direction for emergency access. All plans must be approved by the GSA and the fire marshal as the designs are further developed. Historic Circulation Enhancement/ Modification For fire emergency access for buildings within the landscape protection zones, efforts should be taken to ensure that the new engineered surfaces blend in with the surrounding landscape. New materials should match surrounding materials while incorporating features that will distinguish the route from the historic circulation pattern. In some locations, the historic roadway does not adequately provide for the turning radii of modern emergency vehicles. In these situations, the outline of the historic radii should be retained, while the expanded radii are constructed with complimentary materials. Additional consideration must also be given to the locations of fire hydrants, siamese connections at buildings, and to the requirements for sprinkler (versus non-sprinkler) buildings.

Shuttle Bus Routes St. Elizabeths West Campus will have a shuttle bus service for employees and visitors. The employees and visitors can connect to external shuttles, to other DHS locations and to the Metro at Gates 1, 2 and 4. The shuttle bus routes shown on Fig 31 Shuttle Bus Route, page 229 need further development for individual routes and schedules. Three types of Shuttle Stops are recommended for the Campus. Bus Stops: • Bus stops will be generally located at the staff entrances of office buildings. The locations may be coordinated with building awnings. Multiple stops will be provided for large buildings or buildings with widely separated access points along the shuttle route. Clusters of smaller office and / or shared use buildings, all major shared use facilities (such as USCG Exchange / fitness center - Building 49); conference and training - Building 37; food service - Building 33; Center building - Building 2; Letter buildings, etc. can share stops. Bus Shelter: • Free Standing bus shelters should be provided for areas outside of the primary visual zones, as identified by the Landscape Preservation Plan (Chapter IV, Views and Visual Relationships). The design of these shelters can be based on the vocabulary of the historic Summer House on Campus. See the schematic details for Shuttle Bus Shelter Options in Chapter IV. Bus Shelter Incorporated in Architecture: • Bus shelters should be provided at locations where large numbers of people would typically gather to wait for shuttle buses, including parking garages (multiple locations for large garages) and/or gatehouses connected with parking garages at Gates 1, 2, and 4. These shelters can be either free-standing or incorporated in the new building program.

Emergency Access During Construction Phasing Emergency access will also be required throughout the construction phases, which must be coordinated by the GSA’s appointed construction manager.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Pedestrian Circulation The walkway network on the Campus is designed both to provide pedestrian access during the construction phases, as well as to support an upgraded functioning campus after full build out in 2016. The Circulation 2016 plan included in the Landscape Preservation Plan (Chapter IV, Circulation) outlines the pedestrian network. This network includes rehabilitated historic walkways as well as new sidewalks and trails; see Fig 32 Campus Walks, page 230 . Pedestrian Flows/ Movement (am, pm, & noon) Based on surveys conducted for the DHS Headquarters Consolidation at St. Elizabeths (Transportation Management Program report), pedestrian movement patterns on the campus will likely be heaviest in the morning and evenings; see Fig 33 Pedestrian Flow Analysisam/pm, page 231 . Midday traffic during lunchtime will also probably be heavy; see Fig 34 Pedestrian Flow Analysismidday, page 232 . Because the campus is intended to be predominantly pedestrian, it is essential that the circulation network accommodate the demand. If demand is not met, the adjacent landscape may be impacted. If there is no existing walkway, people will take the shortest route between two points forming “desire lines” across the landscape. Over time these “desire lines” will erode and degrade the ground plane. If walkways are not wide enough for projected volumes, the edges will receive heavy foot traffic and also erode. It is the intent of this report to retain the historic circulation patterns and widths wherever possible. It is also understood that, because of its pedestrian nature, spillover foot traffic may need to be accommodated in the roadway. As the campus population increases, highuse pedestrian routes should be monitored to ensure that they can accommodate the demand. Historic Walkway Rehabilitation All walkways on the historic campus will be rehabilitated. Widening of historic walkways should follow the guidelines provided by the Landscape Preservation Plan and should use the construction techniques illustrated in Chapter IV of this report. The historic alignments should remain visible and retain the historic materials. Any additional segments should be complimentary in treatment and significantly different in character so that new introductions will not be confused with historic features. See the Hardscape Materials Framework Section for character and material guidelines for the historic walkway rehabilitation.

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New Walkway Construction New construction of walkways and trails should adhere to the materials discussed in the Landscape Preservation Plan and the construction techniques detailed in Chapter IV of this report. Concrete walks with new alignments should use the identical concrete mixes and scoring patterns shown in the Outline Specification Section of Chapter IV. However, these new sidewalks should not mimic the historic walkways. The locations of all historic and new routes are shown in the 2016 Circulation, Elements & Objects plan included in the Landscape Preservation Plan (Chapter IV, Circulation) as well as on Fig 32 Campus Walks, page 230 . New walkways should be designed and constructed to cause minimal disturbance to the landscape protection zones. Temporary Walkway Construction Temporary walkways should be located along existing routes or along the proposed routes shown in the Landscape Preservation Plan. Where it is necessary to provide a temporary, smooth walking surface, degraded historic walks should be repaired with concrete. Care should be taken when replacing or adding temporary walkways within the landscape and individual tree protection zones. See Chapter III and IV for design and construction guidance within Tree Protection Zones. Demolition materials should be recycled and used as a base course for final walkway and roadway construction where possible. Pedestrian Circulation During Construction During the construction phases, all pedestrian circulation should be outside of the protection zones; see Fig 4 Site Protection Zones and Construction Areas, page 202 . Circulation routes should be directed away from areas of potential conflict with construction activity. Barriers and clearly marked routes with temporary signage will help employees and contractors to orient themselves in the evolving landscape. Routes should be flexible so that pedestrian traffic can be redirected with unforeseen construction. Walkways should be wide enough to avoid the severe congestion caused by high volumes of people during peak traffic hours (morning, midday and afternoon). Movement of pedestrian traffic should be coordinated with GSA/ DHS security requirements. The Manual on Uniform Traffic Control Devices (MUTCD) is a valuable resource that should be consulted prior to


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance beginning any construction on site. Some considerations suggested by the MUTCD include: • A safe, convenient pedestrian travel path should avoid leading users into direct conflict with site vehicles, equipment or operations. •

Provide clear and positive work area information throughout the construction zones clearly showing entrances and exits.

Clear paths of debris or other items that may obstruct circulation.

Ensure that all traffic control devices are in a good and safe condition.

Prohibiting pedestrians from entering a work site may be preferable to channelizing pedestrian traffic within construction zones.

Fencing should not create sight distance restrictions for road users.

Movement of work vehicles and/or equipment across designated pedestrian paths should be minimized and when necessary, controlled by flag men.

Access to the work space across pedestrian walkways by workers and equipment should be minimized. This access often creates changes in grade and rough or muddy terrain, which pedestrians will then tend to avoid by attempting non intersection crossings.

Where necessary a canopied walk may be used to protect users from falling debris. These should be sturdily constructed and adequately lighted.

When pedestrian and vehicle paths are routed in close proximity, separation by temporary traffic barrier should be considered.

Temporary Traffic Control (TTC) devices, jersey barriers, and wood or chainlink fencing with a continuous detectable edging are sufficient to define a pedestrian path.

Tape, rope, or plastic chain strung between devices should not be used as a control for pedestrian movement, as they are often hard to see.

ADA Accessibility Guidance Much of the historic St. Elizabeths campus does not meet current code requirements for accessibility. As such, modifications or additions to the historic landscape may be required. Applicable codes referenced in this section are from the American’s with Disabilities Act (ADA)

General Guidance and Strategies Modifications or additions to accommodate accessible routes on campus should use materials that are compatible with the historic character, but can be distinguished from the historic fabric. Some buildings requiring accessible routes may be able to accommodate the necessary changes within the building architecture. Others will require exterior landscape interventions to meet code requirements; see Fig 35 ADA Slope Analysis, page 233 . The materials used for the accessible pedestrian paths should be both historically accurate and compliant with the relevant codes. Some areas of the campus may not be required to meet accessibility standards. In these instances, use of appropriate materials takes precedence. The design teams should confirm the location of these areas with the GSA’s Historic Preservation Group prior to proceeding with documentation. Transitions between accessible and inaccessible routes should be consistent and seamless. Additional areas of consideration include: •

ADA parking will be provided at the parking decks. Vehicular access will not be allowed on campus except with special permission

Shuttle buses and bus stops should be handicapped accessible. Shuttle bus stop design should fit within the historic context, while meeting modern safety requirements.

Crosswalks along accessible routes must be code compliant. In areas where ADA ramps were not present historically, modifications may have to be made to the historic alignment.

Ramps must have rails with landings at every 9 meters (30 feet) with a slope no steeper than 1:12.

In natural areas, where accommodation of accessible routes may involve significant disturbance to ecologically significant areas, accessible viewing areas or platforms should be provided to provide handicapped users with the opportunity to experience these places.

ADA Accessibility during Construction As noted in the MUTCD, additional changes may be required during construction to comply with ADA requirements: •

A continuous, accessible route either around or through the construction site should be maintained throughout construction.

The sidewalk should be a minimum sidewalk width of

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance 900 mm (36 inches). Curb ramps and passing spaces, (a 1.5m x 1.5m or 5’ x 5’ space, every 60 m or 200 feet), must be added to this minimum width. •

Maintain a smooth surface to avoid tripping hazards and to maximize wheelchair accessibility.

All barriers and channeling devices should be detectable by pedestrians with visual disabilities. Caution tape alone is not adequate or acceptable.

• •

Audible devices for those with visual disabilities should be considered. Temporary nighttime lighting should be provided for pedestrian walkways throughout the construction zone.

Site Amenities

The new campus requires outdoor spaces for social interaction. New site amenities and new landscapes should be compatible with the historic landscape as recommended in the Landscape Preservation Plan. Some of these amenities may include outdoor seating (both individual chairs and benches), rehabilitated historic fountains and other water features, rehabilitated historic arbors and/or gazebos, rehabilitated baseball field, and new and rehabilitated fitness stations and trails. Large scale amenities such as amphitheaters should be avoided as they might have a negative impact on the landscape. Other amenities that may be desirable, but may not integrate as well with the historic landscape character, such as bike racks and storage, should be accommodated in the parking garages or within the building program. The designers should also consider combining low-cost, multi-purpose amenities with elements from the existing and historic landscape. For example, jogging trails can be integrated with the security trail inside the secure perimeter, courtyards with outdoor seating can be part of the site designs for either new or adaptive reuse buildings, and a soccer field using portable goals can be located in an existing open green space; see Fig 36 Landscape Amenities, page 234 for ideas on locations and Table 3. Site Amenities Program, page 58 for a potential site amenities program.

CF - Character defining Feature P - Previously present DHS/GSA - Requested by DHS/GSA F- Functional need * to be coordinated with Signage MP ** amenities could be combined with other activities *** can also be incorporated into buildings Sources: STE-HL-CDFs-List-from CLR-Jul09.xls courtesy of Heritage Landscapes; DSH Shuttle Bus Facilities and Site Amenities Guidance dated 15th October 2009.

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Table 3. Site Amenities Program SITE AMENITIES PROGRAM

REQUESTED BY

Recreation/Fitness

▷▷ ▷▷ ▷▷ ▷▷ ▷▷ ▷▷ ▷▷

baseball field Soccer Field** Tennis court Basketball Court&** Fitness Trail/ Security Path Fitness stations Barbeque

CF DHS/GSA CF DHS/GSA DHS/GSA H&DHS/GSA P

Gathering

▷▷ Ceremonial Spaces ▷▷ Courtyards ▷▷ Outdoor seating (small groups to intimate) ▷▷ Benches ▷▷ Gazebo ▷▷ Arbor ▷▷ Summer House ▷▷ Building Entrances/ Thresholds

F F F

P & DHS/GSA CF CF CF P

Transportation / Circulation

▷▷ ▷▷ ▷▷ ▷▷

Shuttle stop*** Bike path** Bike storage / rack*** Service Access/ route

Interpretive Signage*

▷▷ ▷▷ ▷▷

F DHS/GSA DHS/GSA DHS/GSA

F

History Ecology Architecture

Constructed Surface Water Features

▷▷ ▷▷ ▷▷ ▷▷

Fountain Bird bath Pond Runnel

CF CF P F

Stormwater Features

▷▷ ▷▷ ▷▷ ▷▷

Underground cisterns Recharge Beds Retention Basin Swale

F F F F

Maintenance/ Remote Delivery Facility

▷▷ ▷▷ ▷▷

Equipment Storage*** Stockpile areas Receiving

F F F


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Design Character & Hardscape Materials framework6 The guidance for hardscape materials is based on the materials defined in the Landscape Preservation Plan. For schematic details refer to Chapter IV of the report. New roadway surface materials should be coordinated with stormwater concepts proposed in the Phased Stormwater Management Plan section as well as the circulation phasing addressed in Chapter IV. Hardscape materials should also be coordinated with site wide initiatives like LEEDŽ and Sustainable Sites Initiative (SITES™). Throughout the campus, pavements, landscape elements and objects will be restored and preserved to the extent possible. All rehabilitation will be designed to harmonize with and enhance the character-defining landscape of the campus.

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Design Guidance Roads and Curbs Desired Design Character Broad sweeping curvilinear alignments of predominantly exposed aggregate concrete paving with a center line scoring pattern are characteristic of much of the roadways of the historic St. Elizabeths West Campus. The form and character of the present day drives reflect these patterns and materials. Drives throughout the landscape will continue to use the historic alignments and locations. Roads generally measure about 7.3 meters (24 feet) wide for the travel lanes. Drop-off areas (elliptical arches off roadways to approach selected buildings) are generally 2.75 meters (9 feet) to 3.35 meters (11 feet) wide. Over time, many roads have been resurfaced with asphalt. As the historic road network is renewed it is important to retain the historic alignment, scale and materials of these drives.

In collaboration with from Heritage Landscapes

Road Materials and Historic Alignment. Remaining concrete roads follow original alignments and locations. The change in surface concrete in this drive interprets road widening efforts. The original center line score pattern remains evident. Photo R-STE-cdf_20090728_0152.jpg courtesy of Heritage Landscapes.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance All new introductions should be designed to harmonize with the historic character of the campus. Contemporary concrete circulation features must be compatible with the character of historic roads and walkways. New roads should create curvilinear alignments similar to the historic network but use a surface treatment different from the historic exposed aggregate. Construction efforts include: • Rehabilitation of the historic roads to recapture the historic character. •

Return of the asphalt drives in Units 1 and 2 to the historic exposed aggregate paving. (Golden Raintree Drive is the exception.)

Adaptation of the new roads to the geometry and layout of the historic roads.

Historic Road and Curb Materials The primary road material for the historic West Campus is exposed aggregate concrete with a large local aggregate and a center line scoring pattern. The drop-off areas for different buildings are within the same family of materials and details as the historic exposed aggregate concrete walks, however they use a larger aggregate. The historic road network will be rehabilitated by following the construction details seen in the remaining historic concrete roads that are found in Units 1 and 2 today; see the historic concrete roads detail for profile and Fig 27 Campus Roadways, page 225 for location. The primary curb detail used throughout the campus is a rolled curb that adjoins a gutter. There is a joint 609 millimeters (24 inches) from the back of a continuous 152 millimeters (6 inches) concrete curb rising 152 millimeters (6 inches) above the paved travel surface, as shown in the Curb Gutter detail in Chapter IV. In certain locations on the campus granite curbs were historically used; see Fig 27 Campus Roadways, page 225 for curb material guidance. In these places a 203 millimeter (8 inch) wide 152 millimeter (6 inch) high granite curb will be constructed, as shown in the historic granite curb detail in Chapter IV. In the vicinity of Gate 2, 508 millimeter (20 inch) diameter granite vehicle bumpers were also present and will be restored, replaced, or reclaimed as appropriate. See the Security Fence & Gate Houses Package for precise locations and the Granite Vehicle Bumper detail in Chapter IV.

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New Road and Curb Materials Where new drives do not follow historic alignments, new surface applications are permissible. They should be compatible with the historic circulation, but identifiable as contemporary additions. The intent is to use the qualities of the historic materials in the new road layouts with subtle variations in surface treatment that does not create a false impression of genuine historic character or details. Materials for the new major roadway will be concrete with a center joint, crowned profile and 152 millimeters (6 inches) curb (height and width) with a warm beige tone. New or Re-aligned roadways that are not on the plateau, such as the access road from Gate 6 and the entry road approaching the plateau from Gate 4, will be asphalt with concrete barrier curb and granite curb respectively. Minor roadways that were historically gravel, will now be constructed of asphalt pavement; see Fig 27 Campus Roadways, page 225 for specific guidance on materials proposed for vehicular circulation. While the concrete sand/aggregate mix and dimensional standards are constant, future roads can have a broom finish. Other considerations There are several additional requirements that influence the choice of materials for the campus. To fulfill the requirements of sustainability, locally sourced materials should be used. Where subsurface percolation will allow, and soil can drain, pervious asphalt or concrete should be used as part of the stormwater management system to satisfy the regulatory requirements.

Pedestrian Crosswalks and Pavement Markings Crosswalks Pedestrian Crossings should be easily distinguishable from the greater roadway surface while adhering to the historic character of the site. Three possible strategies can be incorporated into crosswalk design: •

As noted in the Landscape Preservation Plan (Chapter IV, Circulation), contemporary brick crosswalks can be introduced to calm traffic and to delineate pedestrian routes. Reflecting the historic brick roadway precedent, red brick should be used in Landscape Unit 1 and yellow brick in Landscape Unit 2. These pavers should only be utilized where brick walks intersect the roadway. They should also be able to withstand the loads of modern traffic.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance •

Where roadways are constructed from concrete, a scoring pattern can successfully demarcate crosswalk locations.

Where roadways are constructed from asphalt, a band of granite block banding can be used to delineate crosswalks.

Pavement Markings Paint markings will meet applicable codes and regulations and will be limited to entry gates and access to parking structures.

Pedestrian Walks, Building Edges/ Plazas, and Edge Restraints

Desired Design Character Walks throughout the campus provide ways for pedestrians to move between buildings and to stroll the grounds, enjoying this scenic landscape. Brick walks were the earliest paving system on the campus, installed in the second half of the 19th century. Historic concrete walks are found throughout the campus with a concentration in Unit 2, (the Pavilion area of the plateau). These walks remain in good condition from the 20th century construction. The historic pedestrian patterns and landscape character should be reinforced by the construction of additional concrete walks. Recaptured concrete walks must match the historic character and original alignments, widths, grade and finishes. New walks should create curvilinear alignments similar to the historic network and reflect a surface treatment subtly different from the historic exposed aggregate. Typically, historic concrete pedestrian walks on the campus are 1.5 meter (5 feet) wide with a center joint and control joints to create a 762 millimeters (30-inch square) pattern with an interior dimple pattern. One site specific concrete walk variation is located at Building 49, the Construction Shops. The variation includes a full 1.5 meter (5 feet) square panel with a tooled edge, an interior dimple pattern and without a 762 millimeters (30-inch square) control joint pattern . This walk should be replicated to match the historic variation; see Fig 32 Campus Walks, page 230 . Red brick walks and paved building edges are located primarily in landscape Unit 1 around the Center building and the nearby building clusters. The historic brick walk system should be rebuilt to match the hard-fired red brick. This brick is laid in a herringbone pattern, as a hand-tight installation without mortar. Different edge details reflect a variety of edge conditions, based on location. It is important to match the historic alignment, scale, and materials of these walks, as the system is recaptured. To reconstruct the brick paved areas and walks that will replace former historic

brick pavement, salvaged original materials should be used, provided they meet current loading criteria. Existing brick pavements removed during construction should also be rebuilt using the original materials. Where required, brick pavers of the same dimensions can be used. While these walks and edges must be built to accommodate occasional vehicle crossing for service access, they should maintain their historic alignments, widths and grades and match original details. Historic Pedestrian Walk Materials The historic concrete walks have an exposed aggregate surface finish. Concrete walks will be constructed with smaller 1/8-inch to ½-inch exposed aggregate and will be restored to match their historic conditions. Historic brick paths will be excavated and re-laid to return them to functional use; see Fig 32 Campus Walks, page 230 for the specific guidance on proposed pedestrian circulation materials. Historic building edges should maintain a character consistent with the historic campus. Brick, laid in a basket weave or herringbone pattern, was the predominant paving material around the buildings in Unit 1 and should be maintained in this location. New Pedestrian Walk Materials Understanding that St. Elizabeths will have to accommodate to new uses, additional materials will be permitted in the locations highlighted in Fig 32 Campus Walks, page 230 . Any new concrete and brick pavement areas must use a pattern that distinguishes them from the historic patterns discussed above. Pedestrian plazas within or adjacent to new building additions (visible from the historic landscape) must use either concrete or red brick pavers. Plazas that may be completely enclosed within the new buildings can use other materials such as granite or asphalt block pavers. Special consideration should also be given to the requirements for underground access to utilities. Stormwater management should be integrated into plazas wherever possible. Designs that minimize the need to salt and plow should also be explored. Edge Restraints All unit pavements should have strong and durable edges. Ease of construction, cost of application and historical context can help to identify the most appropriate material. See Chapter IV for edge restraint details. Curb Ramps New curb ramps will match the materials of the corresponding sidewalk. A perpendicular curb ramp, which intersects the curb at a 90-degree angle, must have

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance flared sides if people are required to walk across them. The slope requirements for the flared sides depend on the width of the sidewalk at the top of the ramp. If this distance is less than 1.2 meters (48 inches), then the slope of the flared sides must be no more than 8.33 percent (1:12). If it is 1.2 meters (48 inches) or more, then the flared sides may slope up to 10 percent (1:10). When pedestrians are not required to walk across the ramp, such as where there is a nonwalking surface (grass, for example) curb ramps are allowed to have returned curbs. A curb ramp with returned curbs must have a landing with maneuvering space at the top of the ramp at least 1.2 meters (48 inches) from the back of the ramp. Curb ramps are also required to have detectable warnings consisting of an integrated series of small domes that contrast in color with the surrounding sidewalk or street. The material for the truncated dome paver should be granite where it is adjacent to granite curb and should be concrete where it is adjacent to concrete pavers. The US Department of Transportation (DOT) encourages these domes to extend the whole width of the ramp, but cover only two feet of the ramp closest to the street.

Landscape Furnishings

Inclusion of some of the historic furnishings can enhance the character of the St. Elizabeths Campus: Benches Benches provide opportunities for individual and social recreation. Over 200 benches on the therapeutic campus attest to the therapeutic and social use of the landscape and the importance of sitting outdoors. Informally positioned, movable benches were flexible and allowed the user to help shape his outdoor experience. Historic photographs and surviving examples of the oak and painted metal strap settee benches can serve as models for new replica benches on the Campus today.

Historic benches were typically 1.3 meters (4feet and 6 inches) long and constructed from metal and wood slats. There are a number of the old historic benches that have survived. Where possible, these benches should be used after restoring them to their original condition. Replications of these benches will enhance the character and use of the historic landscape. Any additional benches should complement the historic character and should be used throughout all the landscape units highlighted in the Landscape Preservation Plan. Bench style within completely enclosed courtyards can be different but should be sympathetic to the historic character. Benches should be located around buildings, in gathering areas and along walkways. See the historic bench and new bench details in Chapter IV. Trash receptacles Trash receptacles were not historically present on the St. Elizabeths Campus. Their use should be limited, especially within character defining view sheds shown in the 2016 Visual Spaces and Views Plan (Chapter IV, Views and Visual Relationships) of the Landscape Preservation Plan. Seasonal use of trash bins can also be considered. The trash receptacles can be located at building entries, trail heads, dining facilities, shuttle bus stops, entry gates, etc. Any receptacles used for garbage should be triple bins for recycling, in a neutral color palette. Dining Tables and Chairs Dining tables and chairs are not permitted within the primary character defining view sheds shown in the 2016 Visual Spaces and Views Plan (Chapter IV, Views and Visual Relationships) of the Landscape Preservation Plan. They can, however, be used in certain courtyards to support outdoor dining activity; see Fig 36 Landscape Amenities, page 234 .

A few remaining historic wood and strap iron benches are found in the landscape today. These historic features serve as models to construct standard bench replicas. (Photo-right- R-STEf_20090728_0068. jpg Courtesy Heritage Landscapes)

Detail of the benches outside the Allison Buildings.

(Photo R-STE-DC1345SE0P001-detail.jpg Courtesy Heritage Landscapes and

National Archives II)

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Landscape Elements

Water Features Ornamental fountains and pools at St. Elizabeths West Campus once served as focal elements in the therapeutic landscape. Three special water features were located near historic buildings. The large pool in the landscape of trees and lawn south of the Center building was the central landscape feature in this space. A tiered fountain was centrally placed in the courtyard south of the Atkins Building. The small fountain in the south Center Building courtyard the only extant water feature in the landscape today, is framed by three building walls, making this modest, tiered water feature, a strong focal element. The water features attracted people and drew them into the landscape. Where possible, water features should be recreated at the locations indicated on Fig 36 Landscape Amenities, page 234 . •

The existing fountain should be preserved and repaired as necessary.

The two missing historic water features should be reconstructed based on historical documentation. Recapture and on-going care of these historic water features will enhance the visual and recreational quality of the landscape.

New water features, ornamental pools, and fountains on the therapeutic campus should match the aesthetic of the historic pond, fountains and birdbaths. Consideration should be given to the historic placement, size, materials, and details of earlier water features where new water features are designed.

The ornamental pools and fountains are important to the overall quality and experience on the St. Elizabeths Campus and deserve to be renewed. Basins should retain a low profile and be set at grade level, with very low coping of stone, brick or, in some instances, cast iron or lead. The basins were circular in form and in several instances have a multiple, tiered cast iron center cascade. The finish of the basin interior was light in color reflecting the color of the water and sky.

A multi-tiered fountain sat at the center of the courtyard defined by the Atkins Building, Detached Dining Hall, and the Relief Building. (Photo R-STE-DC1345SE0P004-flipped.jpg. Courtesy Heritage Landscapes and National Archives II)

The pool south of the Center Building was surrounded by a rail for safety. (Photo R-STE-DC1458SE0P002 flipped cropped.jpg. Courtesy Heritage Landscapes and National Archives II)

The multi-tiered cascade fountain is one of a few remnants of the former south Center Building garden courtyard.

The historic photo of this fountain is shown in earlier in this chapter, in the Vegetation section covering Historic Gardens and Courtyards. (Photo R-STE-cdf_20090728_0038.jpg. Courtesy Heritage Landscapes)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Planters & Urns Planters & Urns should used only in outdoor courtyard spaces or other gathering areas that do not fall within the primary character defining view sheds (as shown in the 2016 Visual Spaces and View Plan of the LPP). These garden elements can be used to reinforce the design of these spaces and should compliment the overall aesthetic of the campus. Shade structures & Arbors Historically there were very few shade structures on campus and they were limited to two summer houses, an arbor and a trellis. New shade structures should be designed to work with the historic character and these structures should be limited to areas outside the character defining view sheds found within the LPP; see Fig 36 Landscape Amenities, page 234 for potential locations. Bus Shelters Bus shelters were not present on the campus, but may be necessary to serve future users of the site. The proposed bus shelters recall the design of the historic summer houses though the use of complimentary materials and dimensions. However, the ornamentation is reduced and the design is streamlined in order to distinguish them as modern additions; see Fig 31 Shuttle Bus Route, page 229 for proposed locations and the bus shelter detail in Chapter IV for the proposed design. Site Walls Historic site walls should be reconstructed to match the materials present on the campus during the period of significance. Depending on the landscape units in which they will be constructed, as defined in the LPP, proposed site walls should use historically appropriate red brick (Units 1, 2) or stone (Units 3, 4, 5) veneer. Dumpster Screening Where necessary, dumpster screening should use materials similar to those found on the existing architecture, to allow these often unsightly features to blend into the historic campus. They will typically be free-standing brick veneer walls. These screened enclaves should be placed away from major entrances to avoid visual intrusion on the landscape and to limit the experience unpleasant smells. Their location should also meet appropriate criteria for trash container standoff distances as found in the UFC. See the brick veneer screen wall detail in Chapter IV for a typical wall section.

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Historic Steps Steps at St. Elizabeths West Campus help pedestrians traverse the landscape and provide access to buildings and destinations. The steps on the St. Elizabeths campus are integrated with the topography and rarely rise above finished grade, with exception of the steps at building entries. Responding to the relatively subtle grade variations on the plateau, steps throughout campus are generally associated with a building structure, providing access to the facility. •

Bluestone and Brick Steps: Bluestone treads with brick risers are sympathetic to the brick structures and the brick sidewalks throughout the campus. Bluestone and brick steps should be stabilized and repaired or rebuilt to match original locations and details. The character and construction of these steps should be preserved, along with the related historic patterns of topography, pedestrian circulation and architecture.

•

Concrete Steps: Concrete should be used to construct steps where concrete was the original step material. These steps were most frequently used at service and safety exits.

New Concrete Steps and Ramps Concrete steps may also accompany new construction on the site. Concrete steps with stone treads should be used for new construction in appropriate locations such as new courtyards. Concrete ramps will be needed at buildings where handicap access is required. Ramps should be designed for the minimum length needed and placed where they can best achieve the desired grades. Whenever possible these ramps should be 5% grade or less and function as a walk. When ramps are required with maximum ADA grades, use 9.1 meter (30 feet) sections at 8.33% maximum slope with a 1.5 meter (5 feet) landing at 2% maximum slope at the top and bottom. Work with starting and ending grades and limit ramps to 9.1 meters (30 feet) in length. When longer ramps are required, they should be carefully integrated with the building facades and the surrounding context. Ramps require handrails on both sides. They must be constructed to meet all applicable codes and standards.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance

Red bricks and bluestone create the risers and treads for these historic steps at the northwest side of the Center Building. (R-STE-July09-CT-0064.jpg).Courtesy Heritage Landscapes)

Concrete steps are situated at a fire exit at the front of the Q Building. (Photo R-STE-July09-CT-0208.jpg. Courtesy Heritage Landscapes)

Bluestone and brick steps connect to a herringbone red brick walk in Unit 1. (Photo STE-cdf_200 10-27(11).jpg Courtesy Heritage Landscapes)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Railings & Fences The small-scale elements and objects on the St. Elizabeth West Campus include railings along the walkways. These railings define the walkways, control access, guide circulation, and maintain safe routes for pedestrians. Historic iron railings and a few sections of iron fences are located primarily in Units 1 and 2. Railings vary in character based on the formality of the setting from decorative castiron posts to more utilitarian pipe rails. The materials and details of remaining historic railings and fences provide models for renewing missing elements. These vertical features of the circulation system give a special depth to the user experience. These elements require preservation, renewal and on-going maintenance.

Four types of railings still remain on the campus with the original character shown in historic-period images. •

Type 1 Railing: Decorative cast-iron hand rail, in their original locations.

Type 2 Railing: Pipe hand rail - a simple fabrication that uses pipe, “t” and elbow components.

Type 3 Railing: Pipe hand rail - a slimmer rail with welded joints at “t” junctions and bent or welded elbows.

Type 4 Railing: Dual pipe guide rail with ball joint fittings is a heavier version of type 3.

Type 1:

Historic railing Type 1 encircles the lawn panel east of the original Storeroom and Kitchen. (Photo-right) Andropogon Associates, (bottom) R-STE-July09-CT-0304crop.jpg Courtesy Heritage Landscapes)

Type 2: Historic railing Type 2 lines a concrete walk at Redwood

Drive. (Photo R-STE-JULY09-CT-0288.jpg, Courtesy Heritage Landscapes)

Type 3: Historic railing Type 3 is depicted in this historic period image.

Here it guides pedestrian movement along this wide path near the original Detached Dining Hall, Building 33. (Photo R-STE-DC1452SE0P006-flipped. jpg Courtesy Heritage Landscapes and National Archives II)

Type 4:

Historic railing Type 4 helps ensure pedestrian safety at the Martin Luther King Jr. Boulevard underpass. (Photo R-STE-July09-CT-0172-crop.jpg Courtesy Heritage Landscapes)

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The historic decorative cast iron and wire fence defines the garden courtyard at the south side of the Center Building. (Photo STE-cdf_20090728_0034.jpg Courtesy Heritage Landscapes)

Cast Iron and Wire Fence One section of decorative fence is located in the courtyards to the east of the Center Building south entrance. This low decorative railing, depicted in photographs, combines cast iron and wire components and served as a defining edge for a courtyard framed on three sides by building walls. Historic fence panels are templates for replica panels that complete the fenced enclosure along the south edge of the courtyard.

Site Lighting7

Design Guidance

A variety of lighting currently exists on the St. Elizabeths campus; however, much of this is not historic in nature. During the Richardson and White Era, two types of pedestrian-scale light fixtures were installed. The first was a teardrop shaped fixture and the second was a standard upright fixture. Fixtures were also installed on the top of the southern entrance piers. Security or large-scale site lighting should adhere to a similar aesthetic. Site lighting should balance concerns for light pollution with legitimate concerns for safety. The lighting for the six residential structures on the campus should be residential in scale. Sweetgum Lane will not be lighted for historical reasons. Generally, the lighting levels should be low throughout the site. Where possible, integrate security lighting (crash lighting) onto site poles or buildings so that the green areas are not dotted with additional light poles. Where possible, lighting of larger streets and adjacent pedestrian pathways should be integrated. Certain landscape features, like the fountain at center building, can also be lit.

Overall Design Guidance

7

contributed by HLB Lighting

The overall lighting design guidance goals are: •

Establish the minimum illumination levels necessary for safety.

Use site and exterior building lighting that illuminates only the areas required for safety and comfort.

Lighting energy consumption should not exceed 80% of the lighting power densities for exterior areas and 50% for building facades and landscape features as defined in ASHRAE/IESNA Standard 90.1-2004.

Fixtures selected should illuminate the paths and roadways and eliminate glare by hiding the light source within the body of the light fixture. Fixtures should be energy efficient, have full cut-off with low or zero mercury content lamps and use solar power where possible. Energy efficient and full cut-off lighting fixtures should be used in public open spaces.

All new lighting should be coordinated with security needs.

As noted within the Landscape Preservation Plan new standards and fixtures should match the historic aesthetic where possible. S e n s i t i v e B u t U n c l a ss i f i e d

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Security Considerations Facilities operating on a 24-hour basis demand a unique set of lighting criteria that do not confirm with the majority of exterior lighting projects. For the Entry Gates at St. Elizabeths Campus, these concerns are amplified because this facility is a security check-point for entry into a secure military facility. To be successful, the lighting design must carefully respond to each of several special lighting criteria. •

Special care is required for the design of the quantity and quality of light supporting the security force at the facility. High luminance ratios may create glare or excessive contrast and shadows for the inspectors, reducing their ability to perform. The wrong quality of light (color, color rendering, directionality, etc.) will detract from the inspectors’ ability to see and understand what they are viewing.

In addition to the concerns of the inspectors manning the Entry Gates, consideration also needs to be given to the constructability and maintenance of the facility. The lighting design should minimize the effort and cost required to build, operate and maintain the fixtures. This will involve coordination with the architect to ensure that all fixtures are in the proper location, have adequate access for maintenance and require minimal attention.

To meet all of the goals for this project, it will be necessary to recognize the latest research and utilize cutting edge, but proven lighting technology. This will ensure that the design will provide the best quality of light with the longest lamp life, while requiring the fewest fixtures. This plan summarizes both research and technical advances in lighting that are pertinent to establishing the lighting criteria and schematic approach for this project. A set of criteria is listed below that represents a summary of lighting advances.

Current Standards The following is a list of lighting standards for this project: •

IESNA – Illuminating Engineering Society of North America

ANSI – American National Standards Institute

ASTM – American Society for Testing and Materials

ASHRAE:Standard 90.1 – Energy Standard for Buildings Except Low-Rise Residential Buildings

CBM – Certified Ballast Manufacturers

ETL – Electrical Testing Laboratories

NEMA – Association

UL – Underwriter’s Laboratories

National

Electrical

Manufacturers

The IESNA publishes lighting recommendations that are considered the North American lighting industry reference standard. Following these recommendations will help produce a project where the lighting has a positive impact on the visual environment and the lighting needs for specific tasks will be met. These recommendations address both general lighting requirements as well as those specific to certain project types based on special conditions. Note that all information from IESNA is taken from the 9th Edition.

IESNA – General Visual Issues There are several conditions that affect visual acuity under night time conditions. Facial recognition The recommended vertical illuminance for facial recognition is 0.25 fc, and for facial identification is 0.5 fc. Facial recognition occurs when a viewer detects another person at a distance. Facial identification occurs when the details of the face can be described. Adaptation For exterior lighting conditions, one physiological condition of the human eye to consider is adaptation. Adaptation occurs when one transitions from low light to high light conditions or the opposite. It can take up to 60 minutes to fully adapt all the way down to extreme low light level conditions (Scotopic vision) after leaving an area of higher illumination. Glare ‘Glare’ occurs when someone experiences either too much light from a source, such as a light fixture, or the overwhelming brightness from a surface compared to its surroundings. Glare can also diminish a person’s visual

Table 4. Exterior Lighting Criteria

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ZONE

HORIZONTAL ILLUMINATION (AVERAGE)

HORIZONTAL UNIFORMITY

CRI

LAMP LIFE (minimum)

LAMP LIFE

Typical Roadway

0.8 fc

6:1 (avg:min)

85+

12,000 hours

CMH, LED or Induction

Pedestrian Walkways

0.6 fc

6:1 (avg:min)

85+

12,000 hours

CMH, LED or Induction

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance performance and become a disability. Where high light levels are required in specific locations, such as inspection areas, and the surrounding area is substantially darker glare is one of the most difficult aspects to address. It is also one of the most difficult to quantify. Luminance Contrast ‘Luminance contrast’ is perceived as the brightness ratio between two objects of different luminance levels. In order to provide quality visual performance and comfort, the luminance ratios, (i.e. the relative brightness levels) of an area in someone’s field of view should be limited to a maximum of 5 to 1 for normally viewed surfaces. Color Rendering There are several parameters available to determine how accurate a light source renders colors. The Color Rendering Index (CRI) indicates how well a light source renders colors compared to a base source. The higher the CRI value of the light source (with 100 being the maximum) the truer a color will appear. A lamp’s spectral power distribution (SPD) indicates which wavelengths of light it produces. In order to render a particular color accurately, that wavelength of light must be present in the light source. A property of HID, fluorescent, and LED light sources is that they emit spikes of light in very narrow spectral ranges. So even though some lamps in these categories might have a high CRI, they will render some colors better than others. At low illuminance levels like those typically found during exterior night lighting conditions, human vision operates within the ‘Mesopic’ range. Mesopic vision occurs between high luminance levels (daylight) called Photopic vision, and extremely low light levels (moonless night) called “Scotopic vision”. In the Mesopic range, the eye is more sensitive to white light, in particular light at the blue end of the spectrum. Although the research is not conclusive, there is evidence that blue-white light provides better visibility at lower light levels than more amber light, such as that produced by high pressure sodium (HPS) lamps.

Lighting Goals

Minimize light “trespass” from the building or the site.

Light trespass occurs when ‘unwanted’ light falls on adjacent properties. Shielding (for example, by internal back shields on pole top mounted fixtures) should be used to minimize light trespass. Exterior luminaires must comply with all local zoning laws.

Zoning laws that address lighting are often based on a desire to control glare and light trespass (for example, “Dark Sky

Ordinances”), or to provide minimum and/or maximum light levels for specific conditions such as roadways. Use consistent lamp correlated color temperature (CCT) throughout the project site.

Controlling the color temperature range of a light source allows the use of different wattages and types of lamps while maintaining a uniform look throughout the facility. All sources should maintain a consistent color throughout the life of the lamps. Coordinate the site lighting with the security CCTV system.

Video cameras have limited luminance (brightness) ranges. Each camera’s make and model has unique lighting requirements. In addition, camera technology continues to advance with the reduction of illumination requirements and the development of new low-light and infra-red cameras. Once the security CCTV system is selected, light sources need to be positioned appropriately to avoid spill into the camera’s lens.

Research in New Technology Ceramic Metal Halide / Lamp Technology Advance High color rendering sources (70+) are recommended to support critical security tasks. Light sources that produce a high CRI are suggested to enhance visual clarity in as many areas as possible, particularly exterior areas where lighting levels are lower. Ceramic Metal Halide lamps have a rated life of up to 30,000 hours, which exceeds that of universal orientation conventional metal halide lamps and rivals that of high pressure sodium. These lamps have the potential to tremendously increase visual acuity through the campus because of their high CRI and optimum color temperature. Light Emitting Diodes / Lamp Technology Advance Light Emitting Diodes (LED’s) have substantially improved over the last few years and advances are expected to continue at an even faster pace in the near future. These lamps provide a stable white LED source with good, controlled color and high CRI values, and have led to the development of increasingly viable lighting fixtures for both interior and exterior use. An additional advantage for exterior lighting (not possible with HID sources such as conventional metal halide, ceramic metal halide or high pressure sodium), is the LED’s ability to come to full brightness as soon as energy is applied. This light can also be dimmed. These two characteristics

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance offer great savings in initial cost by eliminating redundant tungsten-halogen fixtures for emergency lighting and by providing increased security with their ability come to full light output as soon as they are turned on. LED’s provide operational savings through partial dimming during low use periods. Unlike fluorescent sources LED’s are not affected by cold temperatures. They do not need to be protected and carefully specified for proper operation. When a new advancement is made, the quality of product manufacturing varies tremendously. Given the existing offerings, the development of quality fixtures and the continued advances of LED technology LED fixtures should be used for portions of the exterior lighting. The manufacturers selected, however, must be of the highest quality and experience and must have control of all of the technology involved in the development and manufacturing of the fixtures.

LED End of Life Issues Consideration must be given to disposal and replacement of LED’s when they fail or reach the end of their useful life. Some manufacturers are developing replacement LED circuit boards and drivers while others are advocating complete replacement of the fixtures as a more reliable and economical approach. The current 50,000 hour useful life figure, advertised in the industry, suggests a 10-year period before replacement. At that time, the LED’s availability and fixture opportunities may support complete replacement with new fixtures that will likely use significantly less power to produce the same amount of light. Luminaire Family The typical luminaires to be installed throughout the campus are shown in the Hardscape section of Chapter IV. Two different pole heights are used. Taller poles are proposed for larger roadways with greater amounts of pedestrian or vehicular traffic. Shorter poles are used in pedestrian-only areas and provide a more appropriate scale. The XF1 style luminaire is intended for locations where historical site lighting was originally installed. The yellow dots on Fig 37 Site Lighting, page 235 indicate these locations. The XF1 attaches to the supporting pole with a historically accurate ‘bishops crook’ design. The XF2, using a more subdued mounting arm, but with the same optical control, lamping and mounting height 70

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design as the XF1, delivers identical light. This luminaire is used to provide uniform light distribution where there were no historic luminaires. The XF3 has the same optical characteristics as the XF2, but has a reduced wattage and a shorter mounting height. These luminaires are used when a more pedestrian scale or residential feel is desired. In all cases, luminaires are full-cutoff to avoid light pollution.

Exterior Lighting Diagrams Fig 37 Site Lighting, page 235 identifies the roadways where XF1 or XF2 luminaries are used as well as pedestrian areas served by XF3 luminaries. Historically significant locations where XF1 luminaires will be installed are also shown. Fig 37 Site Lighting, page 235 depicts the high security crash lighting system. This system is activated with an alarm and has two basic functions. The first function integrates crash lighting within the roof architecture of the guard booths at the perimeter security fence and provides illumination along the security fence in both directions. The second function uses pole mounted floodlights to illuminate the yellow area shown on Fig 38 Security Lighting, page 236 . It is critical for crash lighting to enable an officer to perceive color. Photopic vision is what the human eye perceives under well-lit conditions. It allows the perception of color when the ‘cone cells’ in the eye are activated. According to the Illuminating Engineering Society of North America (IESNA) Handbook, 9th Edition the human eye cannot see color below a luminance of 3dc/sq meter. This luminance translates to 3fc on green grass and other dark, rich colors but on skin tones it only produces levels of 1 to 3fc. Based on this criteria, pole mounted crash lighting is spaced at 150 ft on center.

Site Signage Signage on the historic campus was very limited. A signage consultant will provide the approved types and locations of signage throughout the campus to ensure that they work with the historic aesthetic.


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Stormwater Management (in collaboration with William H. Gordon Associates)

Approach Stormwater Management Requirements EPA Section 438 requirements for federal properties mandates that the 1.7 inches of runoff [the 2 year storm] be contained on-site. At St. Elizabeths, the first 1.7 inches of runoff must be either infiltrated or harvested for re-use. See Chapter II for regulatory requirements.

Stormwater Management Plan for the St. Elizabeth’s West Campus As part of this report, a stormwater management concept plan was prepared (Fig 48 Stormwater Management Concept, page 246 ), indicating an appropriate range of stormwater management strategies and desirable locations for individual Best Management Practices (BMPs). The stormwater management concept incorporates the following goals: •

Support the natural site hydrology and the historic site vegetation, through the harvesting, and infiltration of precipitation, and through the collection and reuse of groundwater, beyond what is required by code and within the constraints of new construction and the contaminated ash-fill soil.

Minimize or eliminate stormwater entering the combined storm sewer system through best management practices (BMPs).

BMPs such as vegetated swales, green streets, green roofs, meadows and subsurface storage and treatment should improve stormwater quality, minimize stormwater quantity and fit within the general character zones set out in the LPMP.

Harvest stormwater from adjacent building roofs, foundation drainage systems and groundwater springs. Store this water in underground cisterns for reuse.

Create a decentralized stormwater management system that can be phased and includes BMPs for infiltration such as recharge beds and subsurface storage such as cisterns, or if practical the re-use of abandoned structures such as the steam tunnels; see Fig 48 Stormwater Management Concept, page 246 .

critical to reclaim and/or infiltrate this groundwater to mitigate potential draw down. Excess runoff should be directed to overflow into recharge beds. Other surface runoff will be directed to the new pond to be built at the southwest corner of the campus as part of the USCG Facility. The appropriate volumes and proportion of runoff directed to each of these systems will be determined by geotechnical testing and the civil engineer’s water budget calculations; see Fig 44 Preliminary Groundwater Impact Study- existing, page 242 , Fig 45 Preliminary Groundwater Impact Study- construction, page 243 and Fig 46 Preliminary Groundwater Impact Study- proposed, page 244 . The proposed pond may be used as a primary or secondary water source for irrigation and fire suppression. All stormwater for reuse or infiltration should be pretreated as per DDOE regulations. Structures such as underground sand filters, UV sterilizers, and water quality catch basins must be visually discrete to be compatible with the historic campus landscape. Site drainage areas will be slightly different post construction from what currently exists; see Fig 47 Post-development Watersheds, page 245 .

Design Guidelines for Proposed BMPs Vegetated Swales Vegetated swales are used to convey stormwater and are modeled on natural drainage channels. Plants adapted to these conditions are both drought and flood tolerant. Vegetation planted in these swales should have deep roots, which help slow the velocity of the stormwater and increase the infiltration capacity, which in turn reduces peak flow. In addition, the micro-organisms on these plants, breakdown pollutants and clean the water. These vegetated swales can be extremely attractive with native wildflowers blooming during the growing season. They help structure the site, by calling out the drainage pattern. They also provide habitat corridors for birds, butterflies and small mammals.

New building construction may impact the perched water table with the proposed subterranean construction. It is S e n s i t i v e B u t U n c l a ss i f i e d

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Cisterns Cisterns are reservoirs built to catch and store rainwater. They can also detain the peak flow of the “design storm” and release it slowly over time. They can be placed either above or underground. Given the important historical nature of the site, only subsurface cisterns are recommended. Cisterns range in capacity from a few liters to thousands of cubic meters and will be sized for the Campus according to the engineer’s calculations. These calculations are based on several factors: •

If irrigation is used, the cistern should maintain a 6 to 8 week supply of water for drought periods common to the project region.

The determination of the volume of water that will be depleted from the perched water table due to the deep construction of the USCG Building and subsurface parking structures.

The determination of whether the water will be reused within a building for toilet flushing, which could possibly be combined with a gray water reuse system.

The requirement to provide detention capacity for the design storm event (the 95th Percentile Rainfall Event), above the storage level for irrigation.

Vegetated swale at Cherokee Park.

Design strategies that increase the efficiency of vegetated swales include: •

If the gradient of the swale is steep (5 %<) the bottom of channel should be reinforced with either and natural matting (coconut fiber), or local stone of varying sizes (river jacks). If these swales also have steep banks, they should be reinforced with jute netting or coir logs and stabilized with planting. If the gradient of the swale is shallow (5%>), the bottom of channel should be heavily planted with vegetation that is both drought and flood tolerant. Meander swale alignment to lengthen the journey, which will slow the water and dissipate its energy. Slowing the water also increases infiltration.

• To collect excess sediment, build check dams within these swales. These dams create steps and pools that also dissipate the velocity of the flow and oxygenate the water.

Check Dam at Washington Cathedral.

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Different types of cisterns include: • Modular storage structures •

HDPE Structures

Precast concrete pipes and chambers

Modular cistern system.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Modular Storage Structures: modular storage structures are usually stackable and are placed underground. These systems should have vertical supports that can handle H-20 loading. HDPE Structures High-Density Polyethylene structures are simply a different kind of cistern and can be custom designed for any site specific requirements. HDPE is a preferred material over other materials due to its environmental benefits (ability to be recycled, is a single compound of carbon and hydrogen and takes less energy to make and transport). Precast Concrete Pipes and Chambers: “On-site, underground stormwater retention /detention accomplishes the capture and storage of stormwater collected from surrounding impervious areas. Riser pipes or curb cuts lead surface storm water to subsurface vaults or systems of large diameter interconnected storage pipes or chambers. Stored water is then released directly through an outlet pipe back into natural waters at rates designed to reduce peak water flows during storms to mimic pre-development conditions. In some cases stored water can be allowed to infiltrate to recharge groundwater (if soil types are suitable and the groundwater table is located sufficiently below the water storage units). Underground stormwater storage provides minimal stormwater quality benefits, but can be a successful addition to a development’s overall stormwater management plan, when coupled with other stormwater BMPs. The addition of pretreatment features at the system’s inlet can improve water quality by removing floatables, skimming off oils and grease, and trapping sediments through deposition. Pretreatment is important if stored water is to be allowed to infiltrate into the soil, otherwise rapid clogging of the system could occur. Pretreatment features can be designed and built into the system or there are commercially available, prefabricated units that can be incorporated within a system during the planning and design. Subsurface storage relies on construction of water storage structures made of concrete (vaults), or large diameter, rigid pipes or arches, with capped ends and made of plastic, steel or aluminum. A number of pre-built, modular systems are commercially available. Storage structures, inlet and outlet pipes and maintenance access (manholes) are fitted and attached in a predetermined excavated area and then the entire area is back-filled to surrounding landscape surface

Infiltration Trench.

height with gravel and subsequently surfaced. Because of ongoing maintenance requirements and the potential of needed repairs at some later date, underground storage facilities should not be built over and preferably should be located in areas where large sized maintenance vehicles can easily operate and excavation remains possible, if required.”(Lake Superior Streams, 2009)

Infiltration Basins The main priority for stormwater management design is to return the rain water to the soil mantle where it can seep into the groundwater. Maintaining the site’s hydrological regime to the extent possible is critical, as the health of the site depends on this complex system.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Filter systems should be designed to handle, at a minimum, the first flush of the design storm. Most regulations do not allow water to pond for more than 24 hours, due to concerns about storage capacity for additional storms and because mosquitoes breed in stagnant water held more than three days. The use of surface basins on the plateau will be extremely limited given the historic character of the campus. However, there are opportunities to incorporate some shallow infiltration basins behind the check dams in the ravines, within the swales to the north and south of the USCG building, and within the interior courtyards of the USCG facility. These basins should be vegetated with plant communities that can tolerate both drought and periods of inundation and provide native habitat.

Recharge Beds

Recharge Bed at Gettysburg Museum.

Some key benefits of infiltration: •

Reduces the amount of runoff

Provides ecosystem benefits through transpiration and evapo-transpiration

Maintains soil moisture

Provides some water cleansing as it filters through the soil

Maintains the baseflow for streams, creeks, lakes, and aquifers

Recharge beds function much like infiltration basins, but are generally located below surfaces such as paths, parking lots and roadways. There are two major ways to get water into these beds below these surfaces. The surface can be a permeable material-asphalt, concrete, etc., or there may be area drains to funnel water in to the bed. The design of these beds is relatively simple and effective. They serve multiple functions, acting as the sub-base for the paving, or planting above. They can be as deep and wide as feasible, to handle the stormwater volume desired. Again, with this particular BMP, the soil must be conducive to infiltration for this system to be successful. The present stormwater plan proposes the use of recharge beds in several locations, each with a different primary function. Recharge beds under the cisterns will handle

Infiltration basin designs can take many different forms. The main function of these systems is to return the water to the soil. The ultimate success of any infiltration strategy depends on the soils ability to absorb and release water. Existing soil should be tested by an engineer and remediated where necessary. Capturing the initial surface runoff of a rainstorm-the “first flush”-is important to minimize water pollution entering storm sewers. This first burst of water typically carries more pollutants than the remainder of the storm, as it “washes” the pavements. 74

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Tree Trench at the University of Pennsylvania.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance any overflow that may occur once the cisterns have reached capacity. Recharge beds are also proposed under the multipurpose trail along the West Access Road. They are also proposed as part of the continuous tree trench system, along the West Access Road. Lastly, recharge beds can be used under roadways, walkways and under portions of the security path. In these instances, the main purpose of this BMP is to infiltrate stormwater into the soil and from there into the groundwater system.

Continuous Tree Trenches The present stormwater plan purposes the use of continuous tree trenches. A continuous tree trench is a long, linear planting bed that frequently parallels sidewalks or streets. These long, linear trenches allow for a greater area of root growth and for the sharing of soil, water and nutrients between individual trees. The current design of the West Access Road allows for a five foot wide planting bed paralleling the cartway, Image 3.22 West Access Road Concept. In this case, a portion of the multi-purpose trail, which covers the planting bed,will be surfaced in porous paving to allow water to reach the trees. The details will show (Chapter IV) that in order to support the pavement and also to avoid conflicts between the tree roots and the pavement base, the recharge bed under the trail must have a depth of 18” or more. This will also allow water to be stored within the trench without drowning the trees. Should the recharge bed fill with water and become completely saturated, the trenches have an overflow connection to the storm sewer system.

Green Street System, Portland, Oregon

Green Streets

Green streets use vegetation to manage stormwater runoff at its source. This natural systems approach reduces flows, improves water quality and enhances watershed health. Green Streets are a system where stormwater runoff from the roadway is directed into a planter where the water is slowed down, filtered (cleansed), and infiltrated. Once the planters and the soils have reached their capacity the water simply flows back out to the street and continues on to the next trench or drain inlet. The stormwater management plan incorporates this system into the design of the West Access Road. Because stormwater in this system flows directly from the street into the planting bed, there is a concern over the use of deicing salts. Alternatives to sodium base deicing salts will be recommended.

“Passive Irrigation” The most effective stormwater management is to deal with the water where it falls and if possible use systems that are low in cost and energy (i.e. gravity systems). Passive irrigation is a BMP that typically picks-up roof drains from buildings and conveys the water through adjacent planting beds. The pipes are usually perforated (preferably HDPE) and wrapped in a filter fabric which allows water from the roof drains to seep through the planting areas, irrigating the plants throughout the Campus. The plantings within the USCG Building Courtyards and along the West Access Road should all be irrigated with this system. No pretreatment is required since roof water is considered “relatively” clean. Water is piped below grade and never comes in contact with human beings (in contrast to a spray irrigation system). These perforated pipes are usually tied into the larger storm sewer system, so when the soil is super-saturated, overflow will be conveyed to the storm sewer system.

Passive Irrigation.

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Major Stormwater Outfalls Ravine north of Sweetgum Lane Most of the ravines on the Campus appear to have been created by ephemeral streams fed from natural springs at the edge of the plateau. A stream and its floodplain are a dynamic environment where the floodplain, the channel and stream bed are continuously changing, the result of natural processes that erode, transport, sort and deposit alluvial materials. In a natural environment, the stream is a dynamic equilibrium maintaining its dimension, pattern and profile over time, neither degrading nor aagrading. Upstream development can upset this balance, resulting in negative changes-erosion and incision of the channel. A new equilibrium may eventually result, but not before the associated aquatic and terrestrial environments are severely damaged. (North Carolina Stream Restoration Institute, 2009). The present ravines on the Campus are all in poor condition. Many of them have been filled in over the years. Of the two ravine systems remaining, the deep channel in the northwest corner of the campus has the only active stream. With the new stormwater management plans, approximately 1/3 of the Campus’s stormwater will be discharged into this natural drainage channel. Design recommendations will be made after the Army Corps of Engineers has made a final classification of these streams. Pond The pond at the bottom of the USCG facility is designed as a retention basin. A retention basin is a BMP used to manage stormwater runoff, to prevent flooding and downstream erosion. Sometimes called a wet pond or wet detention basin, a retention basin is an artificial lake with a permanent pool of water. The pond for the USCG Building sits at the low point of the Campus. This area receives the runoff from the largest watershed on the site (watershed 1). The intention of the pond is to improve water quality, delay the release of stormwater from the peak flow of designed storm events and provide a secondary source of irrigation water and fire suppression. The pond is also a water garden that is one of the main focal points from the lower levels of the USCG Building and from Gates 4 and 5. The edges of the pond will have

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native emergent plant communities that will flower all summer long and a recirculation system to keep the water clear and sparkling. Due to the contaminated soil in this part of the Campus, the basin is lined. There is a significant stormwater outfall structure located at the western end of the pond. A 54� diameter pipe conveys most of the drainage within watershed 1 from the plateau through the contaminated soil of the south ravine to the pond. Water will flow through a series of stepped pools, which will dissipate its energy and trap sediments. Some maintenance will be required to remove the sediment build-up over time; the pond will also need to be monitored on a continual basis for overall water quality.

Watersheds The west campus consists of 6 major watersheds. The majority of the western campus site improvements fall within Watershed 1 and Watershed 2. In the existing condition, Watershed 5 drained to the east and was collected in the storm sewer system located in Martin Luther King Avenue. The current stormwater design has modified this condition as a result of the proposed Gate 3 design and now conveys the drainage from Watershed 5 into Watershed 1. The summary of each proposed watershed is as follows: Watershed 1 In the proposed stormwater design, Watershed 1 consists of 12 sub-sheds that equal 64.48 hectares (159.33 acres), including an offsite area. Watershed 1 contains all improvements associated with the USGC HQ building, a portion of the onsite access road on the western side of the campus, the majority of the existing buildings that are designated to be retrofitted for reuse, security gates #2, #3, #4, #5, and a portion of gate #6, the NOC facility and the future Phase III buildings. For Watershed 1 to comply with Section 438 requirements, the following treatment options include, but are not limited to, the use of green roofs, cisterns for irrigation/building reuse, or infiltration practices where in-situ soils have acceptable percolation rates. For the length of access road that falls within Watershed 1, and where fly ash does not preclude the use of infiltration, continuous tree trenches and green street design approaches may be used to treat runoff.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Watershed 1 complies with LEED SS Credit 6.1 as the pond has been designed to control the peak flows of both the 1/ yr and 2/yr storm events. The increased volume from predevelopment conditions to post-development conditions is reduced by the use of green roof and infiltration systems. For Watershed 1 to comply with LEED credit 6.2, the combination of green roof practices, the permanent pool volume of the proposed USCG HQ pond, and the various reuse practices must be documented to show acceptable water quality treatment. The impervious area associated with the access road will need separate filters that remove provide 80% of the TSS. These practices that satisfy the Section 438 requirements can also be used to document the required removal of the first 25mm (1.0 in) of runoff from the impervious road areas. The HQ pond stores and slowly releases the 2 and 15/yr peak flow rates so that these rates from Watershed 1 will be below pre-development conditions. This satisfies local DDOE water quantity requirements. The pond also holds enough of the upper watershed runoff to allow the remaining water on-site within Watershed 1 and downstream of the pond to remain undetained. The pond also provides enough permanent pool volume to meet the DDOE requirement of treating 12mm (0.5 in) of rainfall to improve water quality. In addition, the pond safely passes the projected 100 year storm and has an emergency overflow weir structure. For Watershed 1, it has also been requested by the USCG that the 25/yr storm event flowing into the proposed USCG pond not be permitted to flow out of the pond and overtop the West Access Road. The HQ pond has been designed to meet this request. Watershed 2 Watershed 2 consists of 4 sub-watersheds totaling 18.48 hectares (45.67 acres). Watershed 2 contains all improvements associated with the future warehouse building, a portion of the onsite western access road, a portion of security gate #6, Sweetgum Lane, a portion of the Existing Center Building rooftop drainage, and a portion of the existing access drives located north of the Center Building. Offsite development associated with the proposed Firth Sterling intersection is included within the extents of Watershed 2. The addition of the offsite area to Watershed 2 is required in order to meet the water quantity requirements for the west campus development and the new Firth Sterling intersection.

Section 438 requirements will be met within Watershed 2 through a combination of irrigation cisterns, infiltration where feasible, and the green roof area required on the future warehouse building. For the portion of the access road that falls within Watershed 2, continuous tree trenches and green street methods for treating runoff will be applied. These measures also provide additional storage capacity that will reduce the peak flow rates. The multiuse trail adjacent to the access road will be a pervious pavement that allows rain water to drain into the tree trench system below. Achieving LEED credit 6.1 is made possible within Watershed 2 by the shift in overall divides between Watershed 1 and Watershed 2. The total area within Watershed 2 is reduced as a result of existing runoff from Watershed 2 being redirected by storm sewer to the outfall of Watershed 1. Because of this shift, the 1/yr and 2/yr storm event peak flows and volumes from build-out conditions are reduced below pre-development conditions. Achieving LEED credit 6.2 is made possible by the use of bio-retention, green roof, continuous tree trenches, pervious paving systems and green street practices. The combination of these controls will be documented to show 80% TSS removal for the 90-percentile storm. DDOE controls for the 2 and 15/yr events are met through the same principle of shifting divides as described above for LEED credit 6.1. No quantity control structure is necessary within Watershed 2. If LEED credit 6.2 is met, then the water quality requirements of 12mm (0.5 inch) will also have been met within this watershed. Watershed 3 Watershed 3 is a relatively small watershed on the site at 1.85 hectares or 4.59 acres. The improvements within Watershed 3 consist of security perimeter upgrades only. Section 438 infiltration practices are not required within Watershed 3 as there is no proposed impervious area. Since there is no increase in impervious area with postdevelopment conditions within this watershed, this area will not preclude the remaining site areas from achieving LEED credit 6.1. If the Section 438 requirement is met within this divide for treating the runoff associated with the existing impervious area, then the intent of LEED credit 6.2 will also be met. Meeting DDOE requirements within this Watershed are not required as there is no increase in impervious area.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Design Guidance Watershed 4 In the proposed stormwater management design, Watershed 4 is a relatively small shed at 1.23 hectares (3.03 acres). Watershed 4 contains all improvements associated with security gate #1 including the new checkpoint building and entrance driveway to the proposed underground parking garage. Because the proposed underground garage is located underneath the majority of Watershed 4, infiltration is extremely limited in this area. However, some infiltration may be possible outside of the underground garage footprint. The use of underground cisterns for irrigation/building reuse could help to meet the Section 438 requirements within Watershed 4. The combination of underground detention and infiltration practices within Watershed 4 work in conjunction to meet the peak flow and volume reductions for the 1/yr and 2/ yr storm events; therefore, achieve LEED credit 6.1 within this watershed. LEED credit 6.2 requirements could be met with water quality inlets that are designed to remove the required 80% TSS from the 25mm (1.0 inch) depth of first flush runoff, or through the proposed infiltration practices that fall outside of the underground garage footprint. DDOE requirements are met through the use of an underground “Rainstore� system. This underground structure will provide peak attenuation for the 2 and 15/yr storm events as required by DDOE. If water quality inlets are used to properly meet LEED 6.2 requirements, then the less stringent DDOE water quality criteria will also be met. Watershed 6 The total area of Watershed 6 is 9.57 hectares (23.64 acres). The majority of this watershed remains offsite with proposed conditions. There is no impervious area planned onsite that falls within Watershed 6. Therefore, this watershed will not preclude the site from achieving the requirements of Section 438, LEED credits 6.1 & 6.2, or DDOE stormwater management requirements.

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Watershed 7 Watershed 7 does not change with post-development conditions except for improvements to the security perimeter fencing. The drainage area remains the same from pre-development conditions at 0.32 hectares (0.78 acres). There is no impervious area planned onsite that falls within Watershed 7. Therefore, this watershed will not preclude the site from achieving the requirements of Section 438, LEED credits 6.1 & 6.2, or DDOE stormwater management requirements.


CHAPTER IV

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Construction Guidance

CHAPTER 4 Construction Guidance

Introduction Chapter IV presents construction guidance, including phasing plans, conceptual details, and an overview of specifications appropriate to this site. NOTE: all details in this section are intended for preliminary design only. They are not to scale (N.T.S.) and are not intended for bid or construction purposes. They are subject to modification based on design calculations, local practices, and all applicable codes and regulations.

Development and definition of construction phasing sequencing and strategy Limits of Disturbance (LOD) Many of the projects identified in Chapter III are in various phases of design. The Limits of Disturbance (LOD) for the West Campus were developed with the intention to keep construction activity close to the existing buildings, protect the ornamental landscape and character defining features on the site, and limit the impact to natural landscapes especially where they are on steep slopes and erodible soils. LODs have been generated using certain criteria: the standards of the LEED and SITES programs, the type, scale and historic significance of each project. Certain projects like the USCG, Security LIMITS OF DISTURBANCE Fence and Gatehouses, Phase 1b Adaptive Reuse, and The Limits of Disturbance (LOD) are defined as the area Phase 1 Utilities are in Design Development Phases and within a project site where a contractor may operate the LOD for these projects has been established and is machinery or disturb the site. The Contract Limit Line (CLL) is defined as the entire project boundary or limit of work. indicated as such on Fig 52 Limits of Disturbance, page 250 This boundary also generally includes areas not to be . Where projects are not fully developed, an approximate disturbed in addition to the LOD. To obtain LEED SS Credit 5.1 (Site Development) site disturbance must be limited to: LOD has been established. The LOD for Phases 2 and 3 40 feet beyond the building perimeter for new buildings; will be refined as concept designs are developed. 10 feet beyond surface walkways, patios, surface parking and utilities less than 12 inches in diameter; 15 feet beyond primary roadway curbs and main utility branch trenches; 25 feet beyond constructed areas with permeable surfaces that require additional staging areas to limit compaction in the constructed area.]

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance The projects on the Campus which will require establishing an LOD can be categorized as: Building Projects: As recommended by the Landscape Preservation Plan, the LOD for the Adaptive Reuse buildings on the Historic Plateau should be 6 meters (20 feet) from the face of the buildings. Within these limits the project designers should protect soils, vegetation, and historic character-defining features as detailed in the Cultural Landscape Report (2009). Detailed protection methodology and guidance is described in Chapter III of this report. The LODs for the new building projects should be a maximum of 12 meters (40 feet) as defined by LEED. While the LEED guidelines for limits of disturbance are written for “greenfield” (undeveloped) sites, the historic importance of the landscape at St Elizabeths makes the use of similar guidance appropriate. It should be less than 12 meters (40 feet) from the face of the building in areas where there is conflict with features recommended for protection. Security Projects: The security perimeter construction is phased. The LOD for the security perimeter for both the interim and final condition is assumed to be approximately 3 meters (10 feet) from the face of the inner and outer fences. However, due to steep slope conditions, the LOD will vary to accommodate the grading necessary to avoid surpassing the maximum slope requirements for the fence. Where necessary, retaining walls should be built to limit disturbance to existing vegetation and soils. The Gate Houses have an interim phase that accommodates security and access needs through the construction phases. The LOD for the interim phase of the Gate Houses should be a maximum of 6 meters (20 feet) from the face of the existing gate houses and 12 meters (40 feet) from the new Visitor Screening areas at Gates 1 through 6 (LEED). The LOD for the security outposts should be designated within the 3 meter (10 feet) disturbed zone identified for the security fence. Due to steep slope conditions on the site, the LOD for the security path will vary to accommodate the grading necessary to avoid surpassing the maximum slope requirements for security vehicles. Utility Projects: The utilities construction is phased. The LOD for the utility tunnel should be a maximum of 2 meters (6.5 feet) from the face of the new tunnel limits.

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The LOD for major utilities outside of the tunnel (sanitary, storm, water, gas, etc.) should be a maximum of 4.5 meters (15 feet) while minor utilities should have a maximum disturbance area of 1 meters (3 feet) on either side of the trench (LEED). Roadway Projects: All construction for the rehabilitation of the historic roadways should be contained within the limit of existing roadways. Disturbance for new roadways should be contained within 4.5 meters (15 feet) (LEED) of both edges of the new construction. Landscape Projects: Disturbance resulting from the preservation, relocation, rehabilitation and introduction of vegetation, soils or stormwater management in the ornamental and natural landscapes should be minimized. Protection methodology and guidelines are described in Chapters III & IV

Construction Phasing, Access, and Staging Since many projects will be constructed simultaneously on the Campus, construction phasing within the context of preservation, restoration, and rehabilitation as described in the Landscape Preservation Plan (LPP) must be addressed. To support a preservation strategy, the LPP identifies Landscape Protection Zones that include protecting soils, vegetation, and historic spaces. Construction phasing, access, security and installation of landscape protection should work in concert, to reduce congestion during partial occupancy. Coordination between the different phases and the reduction of duplication will reduce costs in later phases of construction. The complex phasing needs for sequential phasing requires coordination between all the projects concurrently in construction e.g. USCG, Adaptive Reuse, Security Perimeter and Gatehouses, Utility Projects, Landscape Projects, etc. Sequencing of the Landscape Projects must be coordinated with utility or building projects to minimize future disturbance. A detailed plan of construction to address this integrated phasing should be prepared by the GSA appointed Construction Manager for review with the Design Team. For building construction a strategy has been proposed to “back out” of each completed area from north to south.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance Moving away from occupied areas should also be considered. As the Center Building is completed and occupied, the landscape areas to the north and south should be completed in tandem. The Perimeter Security phasing should follow. Additional considerations will include reviewing security fire and Emergency requirements for occupied areas while construction is in progress.

Construction Phasing and Access Phases 1A & B

Phase 1A starts in second quarter of year 2010. USCG and NOC Phase A projects will begin at this time. The landscape and Site Projects that may begin are the Sweetgum Ravine Restoration, portions of the Phase 1 Utilities , and construction of the new road for future vehicular access to the plateau. While the realignment with corresponding utilities are under construction the existing Sweetgum Lane will be used for temporary construction access for small and medium size vehicles. The Sweetgum Ravine Restoration work is described in detail in Chapter III. Construction access will be along the west perimeter. Two construction check points will be established. A temporary access road will be constructed along the west perimeter to provide the access for construction materials during Phase 1A. Access to the Opportunities Trailer will be allowed though Gate 2; see Fig 54 Phasing and Access- 1a, page 252 . Phase 1B starts in the fourth quarter of year 2010. At this time Phase 1A projects will be in construction while construction begins on Perimeter Security, West Access Road, Phase 1 Utilities, Center Building and Phase 1B Adaptive Reuse Projects. The Woodland Restoration for the western slopes and the ravine behind CUP/ Cogen can start during this phase. The restoration work is described in detail in Chapter III and should be coordinated and phased with security perimeter construction, regulatory restrictions, appropriate planting seasons, and plant material availability. While Phase 1B is in progress, Sweetgum Lane will be the temporary construction access for the plateau. Alternately, contractor and construction access may need to be provided through Gates 1 & 3 respectively. Additional staging areas will also be needed during this phase. Detailed plans for access to the different project sites must be developed. Phase 1B Utilities construction will cut off the eastern construction access to USCG. Pedestrian traffic will need to be directed to the different construction sites. See Chapter III for additional guidance on pedestrian circulation through construction sites; see Fig 55 Phasing and Access- 1b, page 253

Phases 2A & B

Phase 2A projects start in the second and third quarter of year 2011. The projects that will start construction during this phase include CUP/ Cogen, Adaptive Reuse (DHS), Phase 2A Utilities, East Campus Tunnel Connection and NOC Phase B. Site/ Plateau Restoration can also commence during this phase since Phase 1A Utilities will already be in place. Restoration of Sweetgum Lane can also start at this time. Construction access to the different projects will be provided from Gates, 1, 3, 5, and 6; see Fig 56 Phasing and Access- 2a, page 254 . Phase 2B projects start in the second quarter of year 2012. The projects that begin construction at this time include the Parking Garages along Martin Luther King Jr. Ave., Phase 2B Adaptive Reuse (DHS), Phase 2B Utilities. Plateau and woodland restoration should be ongoing during this Phase. Gates 1, 3, 5, and 6 will continue to allow construction access; see Fig 57 Phasing and Access- 2b, page 255 .

Phases 3A & B

Phase 3A will begin in the second quarter of year 2013. The projects that will start construction at this time are Adaptive Reuse (TSA, CBP, ICE, USSS), new construction (TSA, CBP, ICE, USSS), Remote Delivery Facility (RDF), and Phase 3 Utilities. The site and Landscape projects include the restoration of staging areas as well as the restoration of the south ravine within the bald eagle protection buffer (to be determined). Projects which will come on line during the second quarter of year 2013 include USCG, Perimeter Security, West Access Road, Phase 1 Adaptive Reuse, Phase 1 Utilities, NOC, and CUP Cogen. The Site and associated Landscape projects will also be completed at this time. New roadway access from Gate 6 will allow delivery access to the plateau. Gate 3 will be used for construction access. All staff, visitors and deliveries will use Gates 1, 4, 5, and 6 during this period; see Fig 58 Phasing and Access3a, page 256 . Phase 3B will start construction in the third quarter of year 2014. The projects that will begin at this time are Phase 3B Adaptive Reuse (TSA, CBP. ICE, USSS), new construction (TSA, CBP. ICE, USSS), and miscellaneous Site/ Landscape Projects. During the same period the projects that come online include NOC Phase B, Phase 2A Adaptive Reuse, Phase 2B Parking Garages, Phase 2B Adaptive Reuse, and Phase 2 Utilities. Most of the site/

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance Landscape projects will be complete at this time, Gates 1, 2, 4, 5, and 6 will be used for staff, visitors and deliveries. No construction access will be allowed through these gates. Phase 3B will be completed and will come on line in the year 2016. Gate 3 will only be used as an emergency access. At this time all gates will be operational; see Fig 59 Phasing and Access- 3b, page 257 .

Staging and Laydown Staging and laydown areas will be needed throughout the construction process. These areas should be coordinated with landscape protection zones identified in the Landscape Preservation Plan. The soils that are suitable for laydown have been identified by Craul Land Scientists. Laydown and staging are proposed on areas that have poor quality soils and will take an enormous effort to remediate, and areas that will be disturbed in the future for new building construction. See Chapter III for additional guidance on soils as well as the Soil Management Section of this Chapter for construction guidance. Coordinate selection of these areas with the guidance for landscape protection and tree protection zones in Chapter’s III and IV. A number of the proposed laydown and staging areas are within the limits of disturbance of various projects. Therefore, these will only be used in the interim period before construction of the related project starts. The goal is to use as much of the existing pavement as possible for staging and laydown activities. The areas marked with an (*) should be further reviewed before conversion into staging and laydown; see Fig 53 Proposed Laydown, page 251

Phase 1A

(1) Laydown for USCG (In use): The access to this area should be constructed with techniques that ensure minimal disturbance to the stream and the Sweetgum Lane Ravine. (11) This area will be disturbed during Phase 1 Utilities and Adaptive Re-use construction and can be used as laydown in the interim until construction begins. (12) The soils in this area are suitable for laydown. There are existing historic trees along the edges that should be protected with fencing around the tree protection zones.

Phase 1B

(2*) The soils in this area are identified as gravely sandy loam fill and are appropriate for laydown. The asterisk * indicates that this area should be utilized only if necessary.

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Further review is required before conversion into staging and laydown. (3) The soils in this area are identified as gravely sandy loam fill and are appropriate for laydown. (4) This area is the site of the future parking deck at Gate 1 and will be disturbed in Phase 2B when the new parking garage is built. Soils here are currently identified as pristine natural soil and mixed natural soil and should be salvaged for future uses. This area will be outside the interim security fence and needs further coordination with GSA/DHS regarding access and security. (5) This area is similar to (4), but is the site of the future parking deck at Gate 2. Portions of this area contain pristine natural soil that should be salvaged for re-use. Existing trees in this area should be protected during the interim construction phase. However, these trees will be removed when the parking deck is built. (6) Existing pavement that can be used for laydown until final landscape is installed. (7) Existing pavement that will be removed in the proposed design. It can be used as laydown until the final landscape is installed. It may also need to be reconfigured to allow for a fire lane and turn-around. (8) Existing tennis courts that can be used for laydown until the helipad construction begins. (9) Existing pavement that will be removed in the proposed design. It can be used for laydown until a fire lane is constructed. (10) Existing pavement, to be removed can be used for laydown until fire lane is constructed. (13) Existing pavement that can be used as temporary laydown until resurfaced (14) This area can be used in the interim for staging and laydown until Phase 1 Utilities / Adaptive Re-use construction begins. (15) The soils in this area are suitable for laydown. (17) This area is a future Phase 3 building site, with soils suitable for laydown. This area needs further coordination


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance with Phase 3 design and construction sequencing. (19) Existing pavement that can be used during early phases until Phase 3 Utility Tunnel construction begins

(20) Existing roadway that can be used for vehicular movement. This area will only be laydown until East Campus access / Phase 2 Utility Tunnel construction begins.

Large tree moving: tree preparation should begin the growing season prior to the move. Moves are best done when tree is dormant with adjustments for species.

Plant procurement: some specialty plants need to be ordered well in advance. Tree species not common in the trade will need to be ordered and dug in the early spring to ensure availability. Native perennials, especially in large quantities, may need to be contract grown and should be ordered four to six months ahead of the planting date.

Soils testing and procurement: quality control of soils requires advance testing of soils, new soil components and proposed amendments, and retesting of the final soil mixes. This process should be begun at least six months in advance of the planned date for soil placement.

Planting: should be performed in between spring or early summer, or in the mid fall. Do not plant in midto late summer. See outline specifications for precise dates.

Seeding: must be performed in spring or fall. Do not seed in summer.

Specialty materials: may need several weeks lead time for manufacture and delivery. Six to 12 weeks is not unusual.

Site Protection Fencing: should be in place prior to commencement of general construction activity.

for more detail.

Phase 2A

(5) This area is over the future parking deck at Gate 1. It will be outside of the interim security fence and needs further coordination with GSA/DHS regarding access and security. A portion of this area contains pristine natural soil that should be salvaged. Existing trees in this area should be protected during interim design phase, but will be removed with the construction of the parking deck. (16*) This area is a future Phase 3 building sit. Portions of the soil are identified as gravelly sandy loam fill. The remaining area contains pristine natural soils that should be salvaged for future use. The existing tree in the center may be protected or salvaged. The asterisk* indicates that this area should only be utilized if absolutely necessary and further review is required before conversion into staging and laydown.

Phase 2B

(18*) This area is a future Phase 3 building site with soils suitable for laydown. White areas are historic cut/fill. The asterisk * indicates that this area should only be utilized if absolutely necessary and further review is required before conversion into staging and laydown.

Time Sensitive Issues Some aspects of landscape construction have long lead times and may require advance implementation by the GSA or general contractor ahead of the general landscape work. Others have specific seasonal limitations for successful implementation. These items typically include: •

Eagle Nest Buffers: regulatory restrictions apply for permanent activities within the 203.1 meters (660 feet) buffer zone. Seasonal restrictions (approx. November through July) apply to construction activity within the 203.1 meters (660 feet) buffer zone, and to non-vehicular activity within the 91.5 meters (300 feet) buffer zone. Avoid blasting and other loud events within a half mile of the nest during the breeding and nesting season (approx.. November and July). See Chapter II

Site Protection The St. Elizabeths campus has significant historic open spaces, high-quality (but fragile) soils and mature trees that all require protection from construction activities. These areas must be barricaded during construction; see Fig 4 Site Protection Zones and Construction Areas, page 202 . The remaining areas on the site should also be treated with a level of care appropriate for a National Historic Landmark. The Site Protection Zones and Construction Areas Plan identifies the areas of protection and construction on the campus: • Within the Site Protection Zone, “Zones of Limited or No Construction” are designated. These areas must be barricaded and must not be disturbed by major construction. However, some minor construction activities may take place within these areas, including the installation of pedestrian walkways, minor site amenities and minor utility lines, as well as the re-building of historic structures and the rehabilitation of forest S e n s i t i v e B u t U n c l a ss i f i e d

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ed with matting.

Where necessary, temporary access may be permitted within the Site Protection Zone, to allow for construction of specific features, such as the security fence. These areas are indicated as “Restricted Construction Access Zones” on the plan. Restricted Construction Access Zones within the Site Protection Zone must be separately barricaded. All construction activity within the Site Protection Zone must conform to protections required for soil and trees.

Tree Protection Zones will require separate barricades when they are located within Restricted Construction Access Zones or when they are located outside the overall Site Protection Zone. The number and location of tree protection zones must be updated as additional tree survey information is obtained.

Tree Protection

Architectural Construction Areas, indicated at existing and proposed buildings, conform to the guidelines presented by LEED. While the LEED guidelines for limits of disturbance are written for “greenfield” (undeveloped) sites, the historic importance of the landscape at St Elizabeths makes the use of similar guidance appropriate. For the purposes of this project, new buildings are shown with a 12 meter (40 foot) offset for construction disturbance, while existing buildings have a 6 meter (20 foot) offset. The configuration of these areas may require updates as building concepts and site designs progress.

• The soil scientist or landscape architect will review soil protection and applicable renovation on a caseby-case basis. •

Tree protection must include the appropriate biological root zone, which extends beyond the canopy drip line; see Temporary Site and Tree Protection details. Tree protection zones for the St Elizabeths West Campus are also indicated in Fig 22 Tree Protection ZonesOverall, page 220 , Fig 23 Tree Protection Zones- 1, page 221 , Fig 24 Tree Protection Zones- 2, page 222 , Fig 25 Tree Protection Zones- 3, page 223 and Fig 26 Tree Protection Zones- 4, page 224 ..

Construction activity must be restricted within tree protection zones. There must be no parking, vehicular use, stockpiling, storage, and staging within the designated root zone. Temporary access for construction of specific, permanent, features within the tree protection zone may be allowed, provided access is defined by secondary fencing, and root zones are protected with matting. Construction techniques for these features should be restricted to specialized ‘tree friendly’ methods.

Pre-construction care, aimed at increasing tree vigor and survival rates, is highly recommended for trees in close proximity to construction activities.

Post construction care, aimed at increasing tree vigor and remediating soil/rooting conditions, is highly recommended for trees affected by construction activities.

Soil Protection

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Restrict construction activity within all Site Protection Zones. There should be no parking, vehicular use, stockpiling, storage, and staging in these areas. Temporary access for construction of specific, permanent, features may be allowed, provided the access is limited through secondary fencing and root zones are protect-

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Avoid working the soil when it has 10 percent moisture content or greater.

Tree protection is essential throughout the construction process, to ensure the survival of the existing mature, specimen trees. Key tree protection concepts and details to be implemented during construction include:

Extended Site Construction Areas may include staging areas, circulation routes, utility lines, security projects, infrastructure development, and stormwater facilities.

Soil protection is essential throughout the construction process. The existing native soils are high quality, fine grained clay loams, with high value for both stormwater absorption and horticulture. However, these soils are extremely fragile and susceptible to compaction damage – especially when wet – which will destroy these two critical functions. Soil protection measures are summarized here, and are further detailed in the Temporary Site and Tree Protection outline specification and details.

Install fencing or barricades around each Site Protection Zone. Where fencing is not possible (e.g. at active roadways), root zone protection should be used.


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Outline Specification: Temporary Site and Tree Protection

1.1

Summary

A.

Protection of historically significant spaces

B.

Protection of existing high quality soils

C.

Protection and pruning of existing forest trees, individual trees and plants that are affected by execution of the work.

1.2

Quality Assurance

A. Owner’s or Contractor’s Arborist Qualifications: Certified Arborist as certified by ISA

1.3 Materials A. Topsoil for Fill: 1. Stockpiled topsoil 2. Planting Soil: Comply with Section “Soils.” B. Organic Mulch: One of the following: 1. Stockpiled wood and bark chips 2. Shredded bark C. Protection-Zone Fencing and Gates: Galvanized steel chain link, 1.8 m (6 feet) minimum. D. Steel Plate

1.4 Execution A.

Pre-Construction Care: Apply growth regulator, compost teas, and supplemental watering, as determined by Arborist, to trees whose Tree Protection Zone lies within the area of construction activity. Apply treatments to trees one growing season in advance of construction and during the growing season (s) throughout construction.

B.

Protection Zones: 1. Enclosed with protection-zone fencing and signage 2. Provide protection matting and additional fencing for temporary construction access. 3. Restricted Activities: a. Construction staging b. Stockpiling c. Construction access except as specified d. Parking e. Excavation except as specified f. Grading except as specified

C.

Root Zone Investigations: As specified.

D.

Trenching near Trees: Air spade excavated under or around roots or tunnel under the roots and roots redirected in backfill areas.

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Crown Pruning: ANSI A300 (Part 1) standard. Pruning to compensate for root loss and as follows: 1. Type of Pruning: Cleaning and clearance 2. Specialty Pruning: Restoration, as indicated on drawings 3. Removed branches chipped and stockpiled on site

F.

Root Pruning: by Arborist.

G.

Regrading: 1. Avoid working the soil when it has 10 percent moisture content or above 2. Lowering grade within protection zone 3. Minor fill within protection zone

H.

Post Construction Care: As determined by Arborist: 1. Soil sprays and drenches 2. Growth regulators 3. Supplemental watering 4. Fertilization 5. Aeration

I.

Tree Replacement: Replacement of protected trees that are more than 25 percent dead or unhealthy due to construction operations. Review removal and replacement with Owner, and obtain written direction prior to removal. 1. Small Trees: New trees of same size and species as those being replaced that measure 150 mm (6 inches) or smaller in caliper size. 2. Large Trees: Tree(s) of 150-mm (4-inch) caliper size, in sufficient quantity that their aggregate diameter is equal to the diameter of the original tree(s) being replaced that measure more than 150 mm (6 inches) in caliper size. Species as selected by Owner. 3. Monetary penalty (amount) for trees damaged by contractor non-compliance with tree protection measures.

1.5 Field Quality Control A. Owner-engaged arborist to direct plant-protection measures and prepare inspection reports. Arborist shall be independent of the contractor.

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Schematic Details: Site and Tree Protection

Tree/Site Protection Fence N.T.S. Not for Construction

Tree Protection Zone N.T.S. Not for Construction

Root/Soil Protection–Pedestrian Access N.T.S. Not for Construction

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Root/Soil Protection Vehicular Access: Light Duty N.T.S. Not for Construction

Root/Soil Protection Vehicular Access: Heavy Duty N.T.S. Not for Construction

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Tree Protection/Root Protection at Existing Roadway N.T.S. Not for Construction

Tree Protection at New Retaining Wall N.T.S. Not for Construction

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Utility Installation in Tree Protection Zone N.T.S. Not for Construction

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SOIL salvage, rehabilitation and Installation11 This section includes an overview of soil salvage, rehabilitation and placement, including an outline specification, and schematic details. Soil management, while often overlooked during conventional construction operations, is essential to the ongoing viability of the historic landscape at St Elizabeths. Similarly, quality control for salvaged soil and new replacement soil is important in the future performance and maintainability of this landscape. Performance testing, storage and acquisition standards, and follow up care are key aspects of this process. Specific tasks related to soil management during construction include: •

Restrictions on construction activity within Site Protection Zones

Soil Salvage. For an overview of potential soil salvage and replacement areas; see Fig 9 Soil Salvage Opportunities, page 207 .

Evaluation of rough sub-grade water infiltration.

Planting soil material acquisition.

Testing and analysis for specification conformance.

Inspection and testing of sub-grade for preparation of sub-grade.

Preparation of mixes and testing for conformance.

Installation and placement of soils.

Decompaction of soils. For an overview of soils assessed as damaged, and needing rehabilitation; see Fig 8 Soil Analysis, page 206 and Fig 10 Woodland Suitability, page 208 .

Mock-up of planting soil profiles.

Final in-place testing of soils.

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Outline Specification: Soil salvage, Rehabilitation and Installation

1.1

Summary

A. Soil Protection (if not covered in Temporary Site and Tree Protection Section) B. Soil Salvage C. Testing D. Remediation, including Decompaction E. Installation

1.2

Quality Assurance

A. Analysis and Testing of Materials B. Installer Qualifications: 1. Soil Supplier Qualifications 2. Testing Laboratory Qualifications

1.3

Submittals

A. Certificates for Products

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1 In collaboration with Craul Land Scientists

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance B. Testing at Prescribed Intervals: 1. Organic Amendments 2. Planting Soil Mixes 3. Sub-grade C. Test Procedures and Reporting: 1. Composts 2. Imported planting soil 3. Infiltration testing of trenches and recharge beds. 4. In-place soil D. Sources for Soil Components and Planting Soils E. Samples

1.4 Materials A. Barricades: as specified in Temporary Site and Tree Protection section B. Protection matting: varies with type of access C. Soil Layers (Horizons): Imported planting soil material D. Organic Amendment: Compost and composted biosolids complying with EPA standards. E. Biological Amendments: compost teas and beneficial mycorrhizae. F. Non-Woven Geotextile Fabric G. Drainage Stone H. HDPE Pipe

1.5 Execution A. Soil Protection: (if not covered elsewhere) 1. Prohibit construction activities within Site Protection Areas 2. Barricades: a. Primary barricades: install surrounding Site Protection Areas b. Secondary barricades: install to delineate temporary construction access, where approved by Owner 3. Use protection matting at temporary construction access within Site Protection Areas 4. Avoid working the soil when it has 10 percent moisture content or above 5. Erosion and sedimentation controls B. Soil Salvage and Stockpiling: 1. Stockpile topsoil and subsoil on separate piles, 6 feet high max. C. Soil Remediation 1. Compacted Soils –Lawn and Regraded Area: a. Loosen compacted soils by scarification, deep ripping, or air spading. b Enhance soil structure with Biological amendments.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance 2. Compacted Soils –Tree and Wooded Areas: a. Enhance soil structure with biological amendments. b. Remediate compaction by air spading, vertical mulching or radial trenching. D. Soil Installation: 1. Coordination: Pre-Installation Examination 2. Delivery, Storage and Handling a. Mixed in ball mill or tub mill 3. Remediate compacted soil conditions prior to placement of new soils 4. Installation a. Place, and work soil under moisture content between 5 and 10 percent. b. Testing as specified 5. New Soil Protection and Repairs e. Protect newly graded areas from traffic, freezing and erosion. E. Infiltration Trenches and Recharge Beds: 1. Place non-woven geotextile fabric in trench or bed area. 2. Place HPDE pipe 3. Place drainage stone in trench or bed area. 4. Test percolation rate 5. Place soils F. Soil Installation Acceptance: Upon satisfactory completion G. Post Installation Maintenance: 1. Restore disturbed areas 2. Clean rain garden, infiltration trench, recharge beds and bio-retention basins of sediment, trash and invasive plants

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Outline specification: Structural Soil Systems

1.1

Summary

A. Section Includes: 1. Structural Cells 2. Geotextiles 3. Geogrids 4. Installation Of Planting Soil.

1.2

Quality Assurance

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance B. Compaction testing results: submit results of compaction testing required by the specifications including the bulk density test of the mock up and installed soil, and the compaction testing log of penetrometer and moisture meter readings to the engineer for approval. C. Soil Structural System Manufacturer’s Product Warranty.

1.4 Products A. Soil Structural System 1. Fiberglass-reinforced polypropylene structures (cells) including frames and decks designed to support sidewalk loads and designed to be filled with soil for the purpose of growing tree roots, and rainwater filtering, detention and retention. B. Anchoring spikes C. Solid and perforated drain and aeration lines 1. Hdpe pipe: corrugated hdpe drainage pipe and fittings. 2. Perforated pipe D. Aeration riser and cap 1. Aeration riser: rigid pipe i. cast-iron soil pipe ii. plastic 2. Cap: Cast-iron E. Geogrid

F. Geotextile 1. Nonwoven geotextile

G. Drainage aggregate base (below cell frame) 1. Drainage aggregate: narrowly graded mixture of crushed stone, or crushed or uncrushed gravel. H. Aggregate base course type 2 (above cell deck): 1. Aggregate base course: naturally or artificially graded mixture of natural or crushed gravel, crushed stone, and natural or crushed sand with at least 95 percent passing a 1-1/2-inch sieve and not more than 8 percent passing a no. 200 sieve. limestone is not acceptable material. I. Backfill material (adjacent to cells): 1 Backfill material: clean, compactable, coarse grained fill soil meeting the requirements of the unified soil classification system for soil type gw, gp, gc with less than 30% fines, sw, and sc with less than 30% fines. J. Planting Soil 1. Panting soil: see planting soil specifications. K. Mulch 1. Mulch shall consist of wood chips.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance L. Root barrier 1. Root Barrier Product

1.5 Execution A. Subgrade Compaction 1. Check compaction of the subgrade B. Installation of geotextile over subgrade C. Structural cell deck installation: install the structural cell decks over the top of each frame stack. install and compact remaining backfill material such that the soil outside the limits of the structural cells is flush with the top of the installed deck D. Installation of geotextile, geogrid, aeration riser and aggregate over the deck E. Installation of paving above soil structural system F. As indicated on drawings G. Installation of planting soil and mulch within the tree planting area 1. Prior to planting trees, install additional planting soil, to the depths indicated, within the tree opening adjacent to paving supported by structural cells

VEGETATION establishment and rehabilitation

Management of Overabundant Wildlife Species

This section includes an overview of vegetation rehabilitation and establishment for both general planting and native forest and meadows.

Ongoing control of the deer population is an important precursor to planting and forest rehabilitation, in order to prevent plant damage from browsing and buck rub, and to ensure the survival of tree seedlings and herbaceous plants. Much of the campus will ultimately be protected from deer browse with the installation of the security fence. However, some planting areas will be outside the security fence, and will require protection. Planted areas near open water (e.g. at the U.S. Coast Guard Building) may also require protection from Canada geese.

Tree protection during construction is an essential component of site management and landscape design strategies at the St. Elizabeths campus. Discussion of tree protection covers both individual tree protection measures and the protection of the existing forest. See the Site Protection section of this chapter for details.

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Outline specification: Temporary Wildlife Controls

1.1

Summary

A. Initial deer population management within the perimeter security fence B. Temporary control of deer browse and mechanical damage to woody and herbaceous plants C. Temporary control of Canada goose browse of aquatic plants and grasses

1.2

Quality Assurance

A. Contractor’s Personnel Certifications: 1. Ecologist to supervise the field personnel, with a minimum 5 years experience in plant identification and applied forest restoration techniques B. Monitoring: Deer browse: 36 months

1.3 Materials A. Temporary Exclosure Fencing: 2440 mm (8 feet) high min B. Tree shelters: polypropelene tubing or wire mesh tubes, 1250mm (5 feet) high. C. Flexible tree wraps D. Repellents E. Stakes: wood or rebar F. Wire or twine

1.4 Execution A. Deer Management: 1. Install exclosure fencing, tree shelters, repellents or other protective materials 2. Application of repellents not to exceed manufacturer’s recommended rates. 3. Remove deer from inside the exclosure: drives or culling. Comply with local, state and federal wildlife regulations. 4. Monitor a. Indicators of deer browse impacts b. Regeneration of native plants 5. Provide additional control measures as necessary B. Canada Geese Management: 1. Control measures may include the following: a. Habitat management: increase height and density of herbaceous vegetation at pond edge b. Harassment: trained dog and handler c. Wire barrier, 150mm – 250mm (6-10 inches) high, marked with flagging d. Repellents: do not exceed manufacturer’s recommended rate 2. Install low-height wire barriers at pond edge 3. Monitor indicators of goose impacts: droppings, browse 4. Provide additional control measures as necessary 96

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Control of Invasive Plant Species The removal and suppression of invasive exotic plant species is critical to plant establishment in meadows and woodland plantings, and in the rehabilitation of the existing woods. Where timing permits, it is most effective to remove existing invasive plants and control the re-sprouts as part of the site preparation work, prior to planting new plant material. Care must be taken not to damage designated native plants in the area, while removing invasive exotics. Subsequent invasive species control should be considered part of a holistic landscape management strategy, coordinated with deer control, maintenance of new plants, and follow up planting.

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Outline Specification: Invasive Plant Control

1.1

Summary

A. Removal and control of invasive exotic plant species in forests and meadows B. Control of secondary establishment and resprouts

1.2

Quality Assurance

A. Contractor’s Personnel Certifications: 1. Ecologist: Ecologist for field supervision of invasive plant removal. Must demonstrate a minimum of 5 years experience in invasive plant removal and forest restoration work, including expertise in plant identification and applied habitat restoration techniques. 2. Pesticide Applicator: State licensed, commercial. B. Monitoring

1.3 Maintenance Service A. Initial Maintenance Service: For initial removals and control of secondary establishment and resprouts: 3 years B. Continuing Maintenance Proposal: For ongoing management of invasive species. Standard yearly (or other period) maintenance agreement, starting on date initial maintenance service is concluded.

1.4 Materials A. Herbicides: Approved by EPA for use near aquatic habitats B. Dyes: Added to herbicide formulation

1.5

Sequencing and Scheduling

A. Phase removals of invasive forest trees, to maintain canopy closure. B. Schedule removals for the most effective seasonal timing, in consideration of method, target species, and risk reduction for adjacent native plants.

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1.4 Execution A. Remove existing invasive plants: 1. Remove in a manner that kills the root stocks in addition to eliminating the above-ground plant. Multiple treatments are typically needed. 2. Vary methods by species and patch size. Include combinations of the following techniques: a. Hand pull young seedlings; prioritize according to the Bradley Method (Fuller and Barbe 1985) b. Weed wack seedlings or herbaceous annuals to prevent seed formation c. Cut woody stems and treat rootstocks with herbicide d. Girdle/wound trunks and treat wound with herbicide e. Paint leaves or lower trunk with herbicide 3. dispose of debris that have the potential to re-root, including vine and shrub cuttings, in landfill. 4. Chip and stockpile large diameter, disease-free branches and trunks on site, as directed by Owner. 5. Herbicide application: a. Apply during native plant dormancy period where feasible b. Spot application methods preferred c. Avoid broadcast or spray applications where alternatives exist B. Control invasive plant resprouts and secondary establishment C. Monitor for: 1. Effectiveness of prior removals; adapt future management as appropriate. 2. Resprouts from previously treated stumps and rootstocks; control as appropriate. 3. Invasive non-native seedling emergence in managed areas; control as appropriate. 4. Native plant re-establishment in managed areas

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Plants This section covers ornamental planting (lawns, tree, shrub and groundcover), meadow planting, young woodland establishment, and forest rehabilitation. Coordinate planting and forest rehabilitation work with the sections on invasive species management and wildlife management. Tree, Shrub and Perennial Establishment: Plants should be installed in the spring (before June 15) and in the fall (after September 15). Do not plant during the summer. Watering should be provided to individual plantings on an as-needed basis, where observation indicates that natural rainfall is insufficient to maintain the health of the plants. The GSA’s preference is to avoid routine watering where possible, since habitually watered plants do not adapt well to local conditions and suffer following the close of the installer’s maintenance period. Meadow Establishment Meadows may be established in various ways, including managed conversion of existing lawn, seeding, planting, or a combination of these techniques. Meadows may be seeded only in the fall or late spring. See outline specifications for Lawns and Grasses, and Plants. •

Conversion of Existing Lawn: This method is viable where native soils are relatively intact, and where field observations suggest that natural regeneration of native meadow plants will occur from the existing seedbank. The method is based on a simplified technique developed for homeowners by the New Jersey Audubon (Matsuoka, T., T. Ettel, and J. Parke. 2008).

Seeded Meadows: This method is appropriate for newly graded areas and other sites with bare soil.

Control of weeds and invasive plants is critical, in particular prior to planting and during the establishment period.

Maintenance of meadow edges is especially important for an attractive presentation of this natural plant community within an institutional landscape. The adjacent lawn needs to be healthy and well-mown. The edge of the meadow may be cut with a flail mower to a shorter, transitional height between the lawn and the mature meadow.

New Forest Establishment (Young Woodland-Future Forest) The planting strategy described here emphasizes the close planting of trees to provide quick shade and suppress

‘old field’ shrubs below. The understory is maintained as a shaded meadow in the short term. Long term, mowing is phased out as a forest ground layer develops. The trees may be thinned, if necessary, as they mature. Existing Forest Rehabilitation Despite several different specific conditions, the rehabilitation of the campus forest will follow a similar process: removal of existing invasive exotics, removal of new invasive seedlings and resprouts, replanting, monitoring and management. Since restoration is inherently an adaptive process (natural systems are complex and specific results are difficult to forecast), the inventory, monitoring, and follow up aspects of the process are essential. Stage 1: Initial removal of existing invasive exotics • Conduct a baseline species inventory, as a reference point for future monitoring of restoration success. Monitoring protocols should be selected to track the general progress of restoration (e.g. Plant Stewardship Index) and/or evaluate specific issues (e.g. invasive species removal). In either case, the quantitative data provided are critical to measure success, correct ineffective efforts and to compare alternative management strategies. •

Prioritize the following: (see also discussion of Forest Rehabilitation in Chapter III)

Woods with predominantly native plants, with a low proportion of invasive species (i.e. most potential future degradation if left unmanaged)

Highly aggressive exotic species which limit native tree reproduction and are difficult to eradicate once well established (e.g. Japanese Honeysuckle vine).

Areas where exotic vines or shrubs represent a security concern

Phase removal of exotic canopy trees, in order to maintain adequate forest canopy cover. Effective control treatments vary by species. In some cases, non-chemical options may exist. Emphasize techniques that minimize soil disturbance and that remove the exotic plants while leaving desirable adjacent plants intact. Herbicide treatments should consider application techniques that apply chemicals only to the target plant and minimize drift to adjacent plants. Avoid spray applications. Stage 2: Control secondary invasive establishment

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Plant larger caliper size trees, if desired. Large tree planting is likely to have minimal conflict with follow up measure for invasive plant control, will help establish useful shade, and will represent visible progress.

Monitor effectiveness of initial invasive species removals. Control secondary resprouts as needed.

Monitor the plants that emerge from the seed bank. If they are predominantly native species, then replanting of sapling trees, seedling trees, shrubs and herbaceous material can proceed (as applicable). If the seedlings are predominantly non-native, an additional round of invasive plant removal may be necessary.

Assess and document the effectiveness of control measures for invasive plants. The re-establishment of invasive exotic plants should diminish, allowing establishment of desirable native plants.

Stage 3: Replanting • Plant native tree seedlings, saplings, and low shrubs, according to the restoration planting plan. If natural regeneration of native trees from the seed bank is sufficiently vigorous, no planting may be necessary. •

Seed native herbaceous plants (wildflowers and grasses), where few native herbaceous plants are present. Plant quickestablishing, generalist species which can create a quick cover and suppress re-establishment of invasive species.

Monitor for new invasive plants during the establishment period. Spot treat new infestations while they are small.

Assess previous invasive species control and adjust management strategies for subsequent years.

Stage 4: Management • Assess native plant growth and regeneration, in accordance with holistic performance benchmarks. These criteria should include: an increase in the abundance and diversity of native plants; more orderly, less ‘messy’ habitat structure, increasing “conservative” (habitat specific) species; decreasing abundance of exotics; decreasing presence of bare soil). Monitor invasive plant re-establishment and control new infestations where they occur. See the Landscape Management Plan (2010) by Heritage Landscapes.

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Outline specification: Turf and Grasses

1.1

Summary

A. Seeded and sodded turf B. Meadow grasses and wildflowers C. Turf renovation. D. Erosion-control materials. E. Grass paving.

1.2

Quality Assurance

A. Installer’s Personnel Certifications: Certified Landscape Technician, CLT-Exterior or Certified Turfgrass Professional, CTP. B. Meadows Installer Qualifications: qualified meadow installer with a minimum of 5 years experience in meadow restoration, whose work has resulted in successful establishment of same.

1.3 Maintenance Services A. Turf: 60 days from date of planting completion B. Meadows: 3 years from date of planting completion

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1.4 Materials A. Seed: As consistent with historic precedent B. Turfgrass Sod: Blend of Turf-type tall fescue varieties. C. Wildflower and Native Grass Seed Mix: 60% minimum to 80% maximum native grass seed. D. Mulches: 1. Straw, certified weed free 2. Fiber mulch and tackifier for hydroseeded areas. E. Pesticides and Herbicides: Approved by EPA for use near aquatic habitats F. Erosion-Control Materials: 1. Biodegradable blankets, fiber mesh or mats 2. Cover Crop G. Grass-Paving Materials: Cellular plastic mats, with planting soil mix.

1.5

Sequence and Schedule

A. Planting restrictions: 1. Lawns: spring or fall 2. Seeded meadows: late spring or fall B. Maintenance restrictions: Avoid spray applications of chemical herbicides which would damage wildflowers growing in the lawns. Spot applications may be used mid-summer through fall to target specific undesirable plants. Do not apply herbicides in the spring or early summer when wildflowers are in bloom.

1.6 Execution – Lawns A. Seeding Method: Sow or Hydroseed. B. Protect seeded areas with straw mulch compost mulch C. Post Seeding Care: 1. Maintain a diverse greensward. Do not remove compatible herbaceous plants such as violets, pussytoes, clover and low-growing wildflowers. 2. Control invasive plant species as needed. See Invasive Species section. 3. Mow between 75 and 150 mm (3 and 6 inches). 4. Repair of bare spots 5. Do not water except to prevent loss of plants 6. Do not fertilize

1.7 Execution – Meadows A. Conversion of Existing Lawn: This method is viable where native soils are relatively intact, and where field observations suggest that natural regeneration of native meadow plants will occur from the existing seedbank.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance 1. Year 1: a. Maintain lawn at 150mm (6 inches) high between spring and early July. b. Stop mowing in early July and observe which plant species come up. Indicators of a successful site will include early successional native plant species such as broomsedge (Andropogon viriginicus). If the emerging plants are predominantly invasive species with few native grasses or wildflowers, consider an alternate installation technique such as seeding or planting. c. Remove any weed species and exotic invasive plants – see Invasive Species Control section.

2. Years 2-3: a. Maintain lawn at 150mm (6 inches) high between spring and early July. The density and variety of native meadow plants should increase each year. b. Remove any weed species and exotic invasive plants – see Invasive Species Control section

3. Year 4+ a. Begin long term maintenance program. b. Additional native grasses or wildflowers may be introduced via plug planting. B. Seeded Meadows 1. Site Preparation: a. Invasive species and weed control b. Soil testing and preparation 2. Seeding Method: Sow with seed drill 3. Protect seeded areas with straw mulch 4. Post Seeding Care: a. Weed control as needed. See Invasive Species section b. Mowing c. Do not water except to prevent loss of plants d. Do not fertilize

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Outline specification: Plants

1.1

Summary

A. Plants and installation B. Planted meadows C. Forest rehabilitation D. New forest establishment E. Vegetated Swales F. Maintenance and warranty

1.2

Quality Assurance

A. Installer’s Personnel Certifications: 1. Planting: Certified Landscape Technician - Exterior, with installation maintenance and specialty area(s), designated CLT-Exterior, or Certified Ornamental Landscape Professional, designated COLP. 2. Forest and Meadow Rehabilitation and Establishment: Ecologist for field supervision of forest restoration work. Installer with demonstrated project success and a minimum of 5 years experience in forest and meadow restoration, including expertise in plant identification and applied habitat restoration techniques. B. Soil analysis as specified in “Soil.”

1.3 Warranty A. Trees, Shrubs and Vines: 12 months B. Perennials and Other Plants: 12 months

1.4 Maintenance Services A. Initial Maintenance Service:

1. Trees and Shrubs: 12 months 2. Transplanted Non-Nursery-Grown Trees: 24 months 3. Perennials and Other Herbaceous Plants: 12 months 4. Meadows: 36 months 5. Forest Restoration Plantings: 36 months B. Continuing Maintenance Proposal: Standard yearly (or other period) maintenance agreement, starting on date initial maintenance service is concluded.

1.5 Materials A. Plants, General: Nursery-grown and complying with ANSI Z60. B. Straight species or heritage varieties where available

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C. Mulches: 1. Stockpiled aged wood and bark chips. Supplemented with aged chips from municipal sources, free of invasive vines 2. Pine needles 3. Compost D. Weed-Control Barriers: 1. Nonwoven fabric 2. Composite fabric E. Pesticides and Herbicides: Registered and approved by EPA, safe for aquatic habitats. 1. Organic Herbicide Alternatives: Sugar, sawdust, and corn gluten meal. F. Tree Stabilization: Only if required by Owner for site conditions: 1. Upright staking and tying 2. Proprietary staking-and-guying device 3. Root-ball stabilization by wood hold-down method 4. Root-ball stabilization by proprietary stabilization device G. Landscape Edgings: consistent with Materials and Hardscape section of the LIP H. Tree Grates and Frames: consistent with Materials and Hardscape section of the LIP I. Root barrier J. Planter drainage gravel and filter fabric K. Miscellaneous Products: 1. Burlap (plastic fabrics not allowed). 2. Mycorrhizal inoculant 3. Root dip 4. Jute Netting

1.6 Execution – Trees, Shrubs and Perennial Plants A. Planting restrictions: spring (before June 15) or fall (after September 15) B. Planting Soil Depth: see “Soils” section. C. Tree and shrub planting D. Mechanized tree spade planting of designated trees. E. Pruning: Prune to remove broken branches, to correct branching structure and to shape. Do not prune to thin. F. Ground Cover and Herbaceous Plant Planting: As indicated. G. Mulching:

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1. Trees less than 300-mm (12 inches) dbh and Tree-like Shrubs in Turf Areas: Organic mulch circle of 75-mm (3-inch) settled thickness with 900-mm (36-inch)] radius. Avoid raised rings and mulch mounds. 2. Planting Areas: 75-mm (3-inch) average thickness of organic mulch extending 300 mm (12 inches) beyond edge of individual planting pit or trench and over whole surface of planting area.

H. Maintenance: 1. Pruning, cultivating, watering, weeding, fertilizing, mulching, resetting to proper grades or vertical position, pesticide treatments as required. a. Watering: Only as needed to maintain health of plants.

1.7 Execution – Meadow Planting A. Deer population control: provided by security fence. In other areas, see Temporary Wildlife Control specification. B. Protection of adjacent plants: 1. Protection during installation of new plants 2. Protection during chemical use C. Invasive species control – see Invasive Species section. Invasive plant control must be addressed prior to planting. D. Soil Treatments: may include, but not be limited to, the following: 1. Mycorrhizal inoculants: to foster the reestablishment of appropriate beneficial soil biota 2. Sugar, or equivalent: to lower soil nitrate levels 3. Corn-gluten pre-emergents: to temporarily suppress annual weeds E. Perennial Plants: 1. Spacing and size as indicated 2. Do not fertilize 3. Water only if needed to prevent loss of plants. Regular maintenance watering is not recommended F. Post Planting Care: 1. Weed control as needed. See Invasive Species section. 2. Repair of bare spots 3. Mowing 4. Do not water except to prevent loss of plants 5. Do not fertilize

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1.8 Execution – Existing Forest Rehabilitation [Restoration] A. Baseline Inventory: Conduct a baseline species inventory, as directed by Owner. B. Deer population control: provided by security fence. In other areas, see Temporary Wildlife Control specification. C. Protection of adjacent forest plants 1. Protection during installation of new plants 2. Protection during chemical use D. Invasive species control – see Invasive Species section. Invasive plant control must be addressed prior to planting. E. Pruning: Prune existing native forest vegetation in consideration of the following: 1. Hazard pruning: within fall-line distance of paths, roads, and fences. 2. Visibility: Thinning within 3m (10 feet) distance of security paths and fences, or as directed by Owner. Do not eliminate all native tree saplings; leave sufficient saplings for canopy tree replacement, as directed by Certified Ecologist. F. Soil Treatments: may include, but not be limited to, the following: 1. Mycorrhizal inoculants: to foster the reestablishment of appropriate beneficial soil biota 2. Sugar, or equivalent: to lower soil nitrate levels 3. Corn-gluten pre-emergents: to temporarily suppress annual weeds G. Tree and Shrub Planting: 1. Balled and Burlapped Trees 2. Bare Root Trees 3. Seedling Trees H. Herbaceous Plants: Seed for temporary cover, weed suppression in new restoration areas, and erosion control. Seed to be regionally native species. I. Post Planting Care: 1. Weed control as needed. See Invasive Species section 2. Do not water except to prevent loss of plants 3. Do not fertilize

1.9 Execution – New Replanted Forest [young woodland-future forest] A. Deer population control: provided by security fence. In other areas, see Temporary Wildlife Control specification. B. Protection of adjacent forest plants 1. Protection during installation of new plants 2. Protection during chemical use

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C. Invasive species control – see Invasive Species section. Invasive plant control must be addressed prior to planting. D. Trees: 1. Spacing and size as indicated 2. Do not fertilize 3. Water only if needed to prevent loss of plants. Regular maintenance watering is not recommended E. Meadow: seeded, or converted from existing lawn. (See Lawns and Grasses specification. Post Planting Care:) 1. Weed control as needed. See Invasive Species section 2. Mow regularly to suppress woody species in the understory 3. Do not water except to prevent loss of plants 4. Do not fertilize

2.0 Vegetated Swales: A. See Rock Work Specification for stone swales B. Place jute netting over planting soils C. Install plug: 1. Spacing and sizes as indicated D. Post Planting Care: 1. Weed control as needed. See Invasion Species section 2. Do not water except to prevent loss of plants 3. Do not fertilize

Schematic Details: Plants

Herbaceous Planting N.T.S. Not for Construction

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Shrub Planting N.T.S. Not for Construction

Vine Planting N.T.S. Not for Construction

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Tree Planting

N.T.S. Not for Construction

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New Forest Establishment Details:. This detail represents the conversion of existing lawn areas to a forest condition. •

Plant caliper-size trees, of predominantly fast-growing pioneer species. Tree spacing can vary, but should be wide enough to permit manual mowing below, yet close enough to provide quick shade (typ 8-12 feet on center).

For large areas, allow occasional gaps between groves to create glades and sunny openings.

Existing lawn: mow high (6 inches) in spring and early summer. Stop mowing in early July and monitor native grass and wildflower establishment. Remove aggressive exotic species such as Canada thistle; appropriate techniques vary by species. Mow back annual weeds with a weed wacker before they set seed.

Bare soil (regraded areas): Seed with a mix of fast-growing native grasses and herbaceous plants, including annuals and biennials. Add a nurse crop. Mow to maintain the native grasses at 6-8 inches high the first year. Remove exotic weed species as they occur.

Consider planting drifts of shade-tolerant wildflowers such as black-eyed susan, butterfly weed, and native sunflowers for visual effect.

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Stage 1: Tree planting and lawn conversion to short meadow

Stage 2: Young (pole-stage) Woodland

As trees grow large enough to provide consistent shade, mowing may be reduced to once or twice per year, and eventually phased out.

Trees will develop into a dense stand of relatively even-sized individuals. As they mature, trees may be thinned to promote some species (e.g. oaks, maple) over others. Canopy cover should remain over 70%.

Monitor for invasive plant species and remove new infestations before they spread.

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Young Woodland Establishment N.T.S. Not for Construction

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Forest Rehabilitation Details: Sunny south and west-facing forest edges (includes fence line corridor) At the St. Elizabeths West Campus, the forest edge is one of the most visible parts of the upland forest communities, and creates the frame between the forest setting and the historical campus itself. Vines are a major problem and their removal is critical for an attractive edge. The south and west-facing forest edges are generally “tapered” edges representing all the layers of the adjacent forest—including canopy trees, flowering understory trees, shrubs and herbaceous layer – which suppress weedy species and provide important shade for the interior forest. The shrub and sapling layers may be thinned for visibility, but (for practical reasons of weed control) should not be eliminated.

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Remove aggressive exotic plants, including shrubs and vines [dashed circles]

Plant seedling and sapling trees at forest edge

Supplement with flowering understory trees and occasional flowering shrubs

Supplement with tall-growing evergreens (optional); limb up for visibility

Seed with a mix of fast growing native grasses and herbaceous plants

Existing native trees and understory trees are to remain. Tall shrubs may be thinned for visibility. Existing trees may be limbed up for visibility.

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Sunny South and West-Facing Forest Edges N.T.S. Not for Construction

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Forest Rehabilitation Details: Shady north and north-east-facing forest edges (includes fence line corridor) North and east-facing forest edges are typically cooler, shadier, and have a more open (porous) structure compared to their south-facing counterparts. Thinning shrubs and saplings should be less intensive and longer lasting. Replanting to suppress weed regrowth can be less dense.

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Remove aggressive exotic plants, including shrubs and vines [dashed circles]

Plant seedling and sapling trees at forest edge

Supplement with flowering understory trees

Seed with a mix of fast growing native grasses and herbaceous plants

Existing native trees and understory trees to remain. Tall shrubs may be thinned for visibility. Existing trees may be limbed up for visibility.

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Shady North and North-East-Facing Forest Edges N.T.S. Not for Construction

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Forest Rehabilitation Details: Forest interior – where native species predominate in the canopy

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Remove aggressive exotic plants (dashed circles), per Stage 1 of the Forest Rehabilitation Process. Prioritize non-native vines and canopy tree species.

Monitor and control resprouts and new seedling exotics, per Stage 2 of the Forest Rehabilitation Process.

Plant many small seedling trees (not needed where natural tree seedling regeneration is adequate). The developing trees may be thinned or limbed up over time where visibility is important.

Supplement with taller sapling trees (optional, for aesthetics and/or quick shade). Caliper size trees may be planted immediately following invasive plant removal.

Seed with a mix of fast growing native grasses and herbaceous plants

Existing native trees and understory trees to remain. Tall shrubs may be thinned for visibility.

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Forest Interior Rehabilitation Predominantly Native Plant Community N.T.S. Not for Construction

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Forest Rehabilitation Details: Forest interior – where exotic species predominate in the canopy It is recommended that invasive species that reproduce in shade be prioritized for removal. Invasive species that require sun to reproduce may naturally drop out of the forest community through time and so may be left temporarily. It is prudent to monitor any new canopy gaps for a spread of these plants from the seed bank). •

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Phase 1

Remove invasive plants (dashed circles), per Stage 1 of the Forest Rehabilitation Process. Prioritize aggressive exotics that reproduce in shade. Maintain a closed canopy of 70% or more.

Monitor and control resprouts and new seedling exotics, per Stage 2 of the Forest Rehabilitation Process.

Plant removal sites with many small seedling trees

Supplement with taller sapling trees (optional, for aesthetics and/or quick shade). Caliper size trees may be planted immediately following invasive plant removal.

Seed with a mix of fast growing native grasses and herbaceous plants

Existing native trees and understory trees to remain, where they occur. Tall shrubs may be thinned for visibility.

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Forest Interior Rehabilitation Predominantly Exotic Plant Community: Phase 1 N.T.S. Not for Construction

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Phase Two Forest interior – where exotic species predominate in the canopy •

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Phase 2

Remove additional invasive canopy trees [dashed circles]. Prioritize aggressive exotics that reproduce in shade. Maintain a closed canopy of 70% or more.

Monitor and control resprouts.

Plant removal sites with many small seedling trees

Supplement with taller sapling trees (optional, for aesthetics and/or quick shade)

Seed with a mix of fast growing native grasses and herbaceous plants

Existing native trees and understory trees to remain, where they occur. Tall shrubs may be thinned for visibility. Phase 1 planting may be limbed up.

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Forest Interior Rehabilitation Predominantly Exotic Plant Community: Phase 2 N.T.S. Not for Construction

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hardscape, site elements and furnishings This section includes the rehabilitation of existing historic pavements, curbs and site structures, and the construction of new built elements compatible with the historic landscape. Key concepts related to hardscape and site furnishings include: • Protect the integrity of historic landscape features throughout the construction process

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New materials and structures should be similar in overall appearance to their historic precedent, but should remain subtly differentiated so as to be discernible to the trained eye.

Maintain site reference benchmarks, materials reference samples, and mockups for both historic elements and new hardscape construction. The GSA and the design consultants shall be responsible for identifying existing site benchmarks and for compiling reference samples; the contractor shall provide mockups. These shall be maintained by the contractor on site for the duration of construction.

New and rehabilitated pavements and site structures should support modern use and meet current code requirements.

Non historic materials identified for removal may be salvaged and re-used, where practicable, when they’re not easily replaced in a cost-effective manner.

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Outline specification: Historic Concrete Paving for Vehicles and Pedestrians

1.1

Summary

A. Historic roads, curbs and gutters B. Historic walks

1.2

Quality Assurance

A. Quality Standard: ACI 301M (ACI 301). B. Mock-ups to confirm constructability and finishes

1.3 Materials A. Reinforcement: 1. Roads, Curbs and Gutter: a. Reinforcing Bars: [Deformed] [Epoxy-coated deformed] [Galvanized deformed] steel b. Joint Dowel Bars: [Plain] [Epoxy-coated plain] [Galvanized plain] steel

2. Walks: a. Welded Wire Reinforcement: Epoxy-coated plain steel

B. Concrete: 1. Portland Cement: ASTM C 150, gray 2. Aggregate: Normal-weight aggregate, local, rounded riverbed gravel, light colors of cream, brown and gray, and these sizes and proportions: a. Historic and New Roads, Curbs and Gutters: 6-mm (1/4-inch) 12-mm (1/2-inch) 25- to 38-mm (1- to 1

30 percent. 50 percent. 20 percent.

½-inch) b. Historic and New Walks: 3-mm (1/8-inch) 10mm (3/8-inch) 12-mm (1/2-inch) 19-mm (3/4-inch)

35 percent. 35 percent. 15 percent. 15 percent.

3. Air-entraining admixture 4. Color pigment 5. Compressive Strength: 4000 psi (27.6 MPa) at 28 days

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1.4 Finishing and Curing A. Finishes: 1. Historic Roads, Curbs and Gutters: Monolithic exposed-aggregate finish; 0.8 coefficient of friction. 2. Historic Walks: Monolithic exposed-aggregate finish with 12mm (½-inch) grid dimpled pattern; 0.8 coefficient of friction. A. Joints: 1. Roads, Curbs and Gutters: a. Spacing: Centerline joint (control or expansion joint) with transverse joints 3.0 M (10 feet) on center. b. Edges: Tooled 6-mm (¼-inch) radius edge with 76-mm (3-inch) smooth border around each panel. c. Width: 12 mm (½- inch). 2. Walks a. Control Joints: 760 mm (30 inches) on center, each way. b. Expansion Joints: Approximately 6 M (20 feet) on center. 3. Edges: Tooled 6-mm (¼-inch) radius edge and 45-mm (1-3/4-inch) smooth border around each panel 4. Width: 6-mm (¼-inch) wide control and expansion joints B. Cure concrete by moisture curing, moisture-retaining-cover curing, compound, or a combination of these.

1.5 Installation A. Road Section: Crowned, minimum 1.5 percent slope B. Walk Section: Maximum 2 percent, minimum 1.5 percent cross slope

1.6 Field Quality Control A. Testing.

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Schematic Details: Historic Concrete Paving

Historic Concrete–Pedestrian N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

Plan

Plan–Alternate

Section

Section - Curb Gutter

Plan

Historic Concrete–Vehicular N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

Section S e n s i t i v e B u t U n c l a ss i f i e d

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Outline specification: New Concrete Paving

1.1

Summary

A. New roads, curbs and gutters B. New walks C. Curb ramps

1.2

Quality Assurance

A. Quality Standard: ACI 301 (ACI 301M). B. Mock-ups to confirm color and finish

1.3 Materials A. Reinforcement: 1. Reinforcing Bars: Epoxy-coated deformed steel 2. Joint Dowel Bars: Epoxy-coated plain steel B. Concrete: 1. Portland Cement: ASTM C 150, gray. 2. Aggregate: Normal-weight aggregate, local, rounded riverbed gravel, light colors of cream, brown and gray, and these sizes and proportions: a. Historic and New Roads, Curbs and Gutters: 6-mm (1/4-inch) 12-mm (1/2-inch) 25- to 38-mm (1- to 1

30 percent. 50 percent. 20 percent.

½-inch) b. Historic and New Walks: 3-mm (1/8-inch) 9-mm (3/8-inch) 12-mm (1/2-inch) 19-mm (3/4-inch)

35 percent. 35 percent. 15 percent. 15 percent.

3. Air-entraining admixture 4. Color pigment 5. Compressive Strength: 27.6 MPa (4000 psi) at 28 days.

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1.4 Finishing and Curing A. Finishes: 1. Roads, Curbs and Gutters: Medium to coarse broom finish; 0.8 coefficient of friction. 2. Walks: Fine broom finish; 0.8 coefficient of friction. B. Joints: 1. Roads, Curbs and Gutters: a. Spacing: Centerline joint (control or expansion joint) with transverse joints 9 M (10 feet) on center. b. Edges: Tooled 6-mm (¼-inch) radius edge c. Width: 12-mm 2. Walks a. Control Joints: 760 mm (30 inches) or 1520 mm (60 inches) on center, each way b. Expansion Joints: Approximately 6 meters (20 feet) on center c. Edges: Tooled 6-mm (¼-inch) radius edge and 44-mm (1-3/4-inch) smooth border around each panel d. Width: 12-mm (¼-inch) wide control and expansion joints C. Cure concrete by moisture curing, moisture-retaining-cover curing, compound, or a combination of these.

1.5 Installation A. Road Section: Crowned, minimum 1.5 percent slope B. Walk Section: Maximum 2 percent, minimum 1.5 percent cross slope

1.6 Field Quality Control A. Testing

Schematic Details: New Concrete Paving

New Concrete Pavement–Vehicular N.T.S. Not for Construction

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Section

Plan Alternate

New Concrete Pavement–Pedestrian N.T.S. Not for Construction

Plan

Isolation Joint New Concrete Pavement Joint N.T.S. Not for Construction

Contraction Joint Score Line Section 128

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Barrier Concrete Curb N.T.S. Not for Construction

New Rolled Curb and Gutter N.T.S. Not for Construction

Adapted from curb gutter detail, courtesy of Heritage Landscapes

Curb Transition N.T.S. Not for Construction

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New Curb Ramp (Type A) N.T.S. Not for Construction

New Curb Ramp (Type B) N.T.S. Not for Construction

Pedestrian Crosswalk (Type A) N.T.S. Not for Construction

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XX

Outline specification: Unit Paving

1.1

Summary

A. Brick unit pavements B. Brick V gutters. C. Brick edge restraints. D. Granite block pavements. E. Rough-granite block pavements. F. Stone edge restraints. G. Metal edge restraints.

1.2 Quality Assurance A. Existing Brick Quality Testing: Owner-engaged testing: 1. Quality Standard: Minimum compressive strength and maximum cold water absorption, percentage: a. Pedestrian: ASTM C 902 for brick class. b. Vehicular: ASTM C 1272, Type F. 2. Mock-ups to confirm color and patterns.

1.3 Materials A. Brick Pavers: 1. Historic Applications: Existing and new pavers to match existing. a. Size: match existing. b. Colors:

1. Pedestrian: Red.

2. Vehicular: Yellow.

2. New Applications: a. Size:

1. Pedestrian: 95 by 190 mm (3-3/4 by 7-1/2 inches) or 102 by 203 mm (4 by 8 inches), by 57 mm

(2-1/4 inches).

2. Vehicular: 95 by 190 mm (3-3/4 by 7-1/2 inches) or 102 by 203 mm (4 by 8 inches), by 57 mm

(2-1/4 inches) b. Colors:

1. Pedestrian: Red.

2. Vehicular: Yellow.

B. Granite Block Pavers: Rectangular granite stones with split faces and edges, surface flamed to remove projections. 1. Size: 127 by 127 mm (5 by 5 inches) by 229 mm (9 inches). 2. Color and Grain: Light gray with medium to fine grain.

continued...

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance C. Rough-Granite Block Pavers: Rectangular granite stones with split faces and edges. 1. Size: 127 by 127 mm (5 by 5 inches) by 229 mm (9 inches). 2. Color and Grain: Light gray with medium to fine grain. D. Edge Restraints: 1. Brick: Equal to pavers. 2. Stone: Set in wet concrete slump. a. Granite: Equal to rough-granite block pavers. b. Sandstone: Red-brown sandstone, 102 mm (4 inches) thick by 305 mm (12 inches) deep by 1.0 to 1.5 M (3 to 5 feet) long; compressive strength, 27.6 MPa (4000 psi). 3. Metal: Aluminum and job-built concrete.

1.4 Installation A. Brick Pavers: 1. Historic Applications: a. Pedestrian: Herringbone, brick on edge where indicated. b. Vehicular: Running bond, brick on edge. 2. New Applications: a. Pedestrian: Running bond, basket weave, or jack-on-jack. b. Vehicular: Running bond. B. Granite and Rough-Granite Block Joint Pattern: Running bond or user defined. C. Aggregate Setting Bed: 1. Aggregate base over compacted subgrade and geotextile. 2. Leveling course of 25 to 38 mm (1 to 1-1/2 inches) over geotextile. 3. Pavers set with 1.5- to 3-mm (1/16- to 1/8-inch) sand-filled joints. D. Edge Restraints: 1. Brick: a. Brick rowlock on edge set on aggregate base and metal edge restraint. b. Brick V-Gutter: Brick set in mortar bed on concrete base with expansion joints 6 M (20 feet) on center. 2. Stone: Set in wet concrete slump. 3. Aluminum edge restraints.

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Schematic Details: Unit Paving

Plan

Section Historic Yellow Brick Pavement N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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Plan

Section Historic Red Brick Pavement N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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Plan

Section

New Yellow Brick Pavement N.T.S. Not for Construction

New Red Brick Pavement Pattern Alternatives N.T.S. Not for Construction

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Plan

Section

Granite Block Pavement at Roadway N.T.S. Not for Construction

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Granite Block Pavement–Pedestrian N.T.S. Not for Construction

Granite Unit Pavement–Pedestrian N.T.S. Not for Construction

Flush Granite Block Edge N.T.S. Not for Construction

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New Brick Unit Pavement Edge N.T.S. Not for Construction

Granite Block Edge–Right Angle Corner N.T.S. Not for Construction

Granite Block Edge–Obtuse Angle Corner N.T.S. Not for Construction

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Brick “V” Gutter with Trench Drain N.T.S. Not for Construction

Adapted from historic red brick “V” gutter detail, courtesy of Heritage Landscapes

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XX

Outline specification: Asphalt Paving

1.1

Summary

A. Hot-mix asphalt paving.

1.2

Quality Assurance

A. Regulatory Requirements: Comply with local DOT. B. Mock-ups of each asphalt type

1.3 Materials A. Asphalt Materials: Comply with local DOT: 1. Asphalt binder. 2. Asphalt cement. 3. Prime coat. 4. Tack coat emulsified. B. Asphalt Mixes: Comply with local DOT. 1. Base course. 2. Surface course.

1.4 Installation

A. Hot-Mix Asphalt Paving: 1. Proof-roll subgrade at locations receiving full-depth asphalt pavement. 2. Apply prime coat over compacted unbound-aggregate base course. 3. Light-Duty Applications: a. Base Course: 76 mm (3 inches). b. Surface Course: 38 mm (1-1/2 inches) with edge restraint. 4. Vehicular Applications: a. Base Course: 127 mm (5 inches). b. Surface Course: 50 mm (2 inches). B.

Restoration at Existing Pavements: Asphalt courses matching existing, joints sealed.

1.5 Field Quality Control A. Testing.

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Schematic Details: Asphalt Paving

Asphalt Pavement–Vehicular N.T.S. Not for Construction

Asphalt Pavement Restoration–Vehicular N.T.S. Not for Construction

Asphalt Pavement–Light Duty N.T.S. Not for Construction

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Outline specification: Aggregate Paving

1.1

Summary

A. Universally accessible pavements.

1.2 Materials A. Aggregate: Hard, durable crushed stone: 1. Base Course: Graded mixture with 90 – 95 percent passing a 9.5 mm (3/8-inch) sieve and not more than 15 percent passing a 0.075-mm (No. 200) sieve. (or the following) Sieve Designation 19.0 mm (3/4-inch) 9.5 mm (3/8-inch) 4.75-mm (No. 4) 2.36 mm (No. 8) 1.18 mm (No. 16) 1.29 mm (No. 15) 600 µm (No. 30) 300 µm (No. 50) 150 µm (No. 100) 75 µm (No. 200)

Percent Passing 100 90 - 95 80 - 90 75 - 80 55 - 65 40 - 50 30 - 40 25 - 35 20 - 25 5 - 15

2. Wearing Course: Graded mixture with 95 – 100 percent passing a No. 4 (?-mm) sieve and not more than 5 - 15 percent passing a No. 200 (0.075-mm) sieve. (or the following) Sieve Designation 9.5 mm (3/8-inch) 4.75-mm (No. 4) 2.36 mm (No. 8) 1.18 mm (No. 16) 600 µm (No. 30) 300 µm (No. 50) 150 µm (No. 100) 75 µm (No. 200) B. Water.

1.3 Installation A. Base Course: 50-mm (2-inch) depth. B. Wearing Course: 50-mm (2-inch) depth. C. Compaction: 95 percent.

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Percent Passing 100 95-100 75-80 55-65 40-50 25-35 20-25 5 - 15


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Schematic Details: Aggregate Paving

Stone Aggregate Mulch N.T.S. Not for Construction

Crushed Gravel Pavement N.T.S. Not for Construction

Crushed Gravel Pavement with Granite Block Edge N.T.S. Not for Construction

Reinforced Turf is only intented for specific locations where historic preservation guidance does not allow for the addition of a paved firelane. See the outline specification for turf and grasses.

Reinforced Turf Pavement N.T.S. Not for Construction

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XX

Outline specification: Stone Curbing

1.1

Summary

A. Historic and new stone curbs.

1.2 Materials A.

Curbs: Granite: 1. Historic: Cleaned, sound existing stone units, or new to match color, grain and finish. 2. New: a. Size: 215 mm (8-1/2 inches) wide, including 12-mm (½-inch) vertical batter, 405 mm (16 inches) high, 152-mm (6-inch) curb height, with 6-mm (¼-inch) bull nose. b. Finish: Thermal on exposed surfaces, sawcut ends and split on back and bottom. c. Color and Grain: Light to medium gray with fine grain.

B.

Concrete: Minimum 20.7 MPa (3,000 psi).

C.

Aggregate base course.

1.3 Installation

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A.

Aggregate base course over compacted subgrade.

B.

Concrete slumps at joints and midsection of long curb units.

C.

Joints: 6 mm (¼ inch) wide, unfilled.

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Schematic Details: Stone Curbing

Historic Granite Curb N.T.S. Not for Construction

New Granite Curb N.T.S. Not for Construction

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Planter Bed Edge or Curb N.T.S. Not for Construction

Granite Block Edge at Curb N.T.S. Not for Construction

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Elevation

Section

Plan

Granite Vehicle Bumper N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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XX

Outline specification: Masonry Steps

1.1

Summary

A.

Historic bluestone and brick steps.

B.

Historic bluestone and brick cheek walls.

C.

New granite steps.

1.2 Materials A.

Brick: Matching existing red brick in dimension and appearance.

B.

Stone Treads: 1. Bluestone. a. Finish: Thermal top, saw-cut edges with drip notch. b. Dimensions: 63 mm (2 ½) inches thick by 355 mm (14 inches) wide by full length of step is less. 2. Granite: a. Finish: Thermal top, saw-cut edges with angled nosing. b. Dimensions: 76 mm (3 inches) thick by 355 mm (14 inches) wide by 1520 mm (5 feet) long or full length of step if less.

C.

Dowels: Stainless steel.

D.

Mortar.

1.2 Installation A.

Match existing masonry coursing and bonding.

B.

Step Treads: Bluestone.

C.

Cheek Walls: 1. Brick: Two brick width (approximately 405 mm [16 inches]). 2. Bluestone: 63 mm (2 ½ inches) to 102 mm (4 inches) thick; pinned to concrete foundation.

D.

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Riser Height: Approximately 178 mm (7 inches).

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XX

Outline specification: New Concrete Ramps and Steps

1.1

Summary

A. Concrete steps. B. Concrete ramps.

1.2

Quality Assurance

A. Quality Standard: ACI 301. B. Mockups to confirm color and finishes.

1.3 Products A. Steel Reinforcement: 1. Reinforcing Bars: Epoxy coated. B. Concrete Materials: 1. Portland Cement: ASTM C 150, Type I/II, gray. 2. Aggregate: Normal weight, local, rounded riverbed gravel, 1/8-inch to ½-inch diameter, light colors of cream, brown and gray.

3. Water.

1.4 Concrete Mixtures A. Compressive Strength (28 Days): 20.7 to 27.6 MPa (3000 to 4000 psi).

1.5 Installation A. Finish: 1. Horizontal Surfaces: Lightly exposed aggregate, slip-resistant (0.8 coefficient of friction). 2. Formed Surfaces: Smooth-rubbed finish. B. Drainage: Minimum 1 percent cross pitch. C. Nosing: Comply with local codes. D. Ramps: Maximum 8.33 percent slope with maximum 2 percent cross pitch.

1.6 Field Quality Control A. Testing.

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Schematic Details: Steps

Detail Riser Elevation

Plan

Elevation

Historic Bluestone and Brick Step N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

New Concrete Steps with Handrail N.T.S. Not for Construction

New Granite Steps with Handrail N.T.S. Not for Construction

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Outline specification: Metal Railings

1.1

Summary

A. Historic and new steel pipe railings. B. Cast-iron railing. C. Woven-wire mesh infill panels.

1.2

Quality Assurance

A. Engineering design of railings and infill panels to meet local code requirements. B. Mockups of each type of railing.

1.3 Materials and Installation A. Historic Railings: 1. Step Handrails: a. Steel pipe and components matching existing. b. Height: Minimum 32 inches, maximum 36 inches. c. Primed and painted, exterior, black. d. Anchorage: Set in stair tread or cheek wall, matching existing. e. Extensions: 1 foot 2 inches beyond top step, 1 foot 7-1/2 inches beyond face of bottom step; comply with applicable codes and standards. 2. Type 1 Railing: Decorative cast-iron in original locations: a. Posts: Facetted 1-1/2-inch diameter. b. Railing: 1-1/4-inch diameter. c. Fittings: Cast 2-3/8-inch diameter ball finial atop connector. d. Height: 31 to 33 inches. e. Primed and painted, exterior, black. f. Post Setting: In formed or core-drilled holes in concrete. 3. Type 2 Railing: a. Posts and Railings: 2-1/2-inch diameter iron pipe, 8 feet on center post spacing. b. Bracing: ½-inch diameter steel rod. c. Fittings: Threaded “T” connectors with threaded elbow connectors at ends. d. Post Base Collar: 1/2-inch high pipe, tack welded to post. e. Height: 2 feet 8 inches. f. Primed and painted, exterior, black. g. Post and Bracing Setting: Set in concrete. 4. Type 3 Railing: a. Posts and Railings: 1-1/4-inch diameter iron pipe, 5 to 8 feet on center post spacing. b. Bracing: ½-inch diameter steel rod.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance c. Joints: Welded. d. Height: 2 feet 8 inches. e. Primed and painted, exterior, black. f. Post and Bracing Setting: In concrete. 5. Type 4 Railing: a. Posts: 2-1/2-inch diameter steel pipe, 8 to 10 feet on center post spacing. b. Rails: 2-1/2-inch diameter steel pipe, dual rails, 1 foot 6 inches and 3 feet heights.. c. Fittings: Threaded “T” connectors with threaded elbow connectors at ends. d. Primed and painted, exterior, black. e. Post and Bracing Setting: In formed or core-drilled holes in concrete. B.

New Hand railings: 1. Posts and Rails: 38-mm (1-1/2-inch) diameter steel pipe. 2. Height: Minimum 865 mm (34 inches), maximum 965 mm (38 inches). 3. Primed and painted, exterior, black. 4. Anchorage: Set in stair tread or pavement. 5. Extensions: 502 mm (19-3/4 inches) beyond top step, 356 mm (14 inches) beyond face of bottom step; comply with applicable codes and standards.

C.

Woven-Wire Mesh: Intermediate-crimp, square pattern, 50-mm (2-inch) woven-wire mesh, 3.5-mm nominal

wire; primed and painted, exterior, black. D.

Concrete Footings: 24.1 MPa (3000 psi).

XX

Outline specification: Metal Fences

1.1

Summary

A.

Decorative cast-iron and wire fence.

1.2 Materials and Installation A.

Posts: Cast-iron to match existing, approximately 1.8 M (6 feet) on center.

B.

Infill: Decorative panel of cast-iron and wire components, matching existing.

C.

Fittings: Bolted and welded connections.

D.

Primed and painted, exterior, black.

E.

Post Setting: In concrete.

F.

Concrete Footings: 20.7 MPa (3000 psi).

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Schematic Details: Metal Railings

Elevation Railing Type 1

N.T.S. Details by Heritage Landscapes Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

Section

Elevation Railing Type 2

N.T.S. Details by Heritage Landscapes Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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Section


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Elevation Railing Type 3

N.T.S. Details by Heritage Landscapes Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

Section

Elevation Railing Type 4

Section

N.T.S. Details by Heritage Landscapes Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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Section

Elevation

Historic Metal Rail with Mesh Guard - Type A N.T.S. Not for Construction

Section

Elevation

Historic Metal Rail with Mesh Guard–Type B N.T.S. Not for Construction

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XX

Outline specification: Masonry Site Walls

1.1

Summary

A. Brick and stone masonry anchored to concrete or unit masonry backup, limited to maximum 4.5 meters high.

1.2

Quality Assurance

A. Mockups.

1.3 Materials A. Brick: Face brick, matching appearance of existing building brick. B. Quartz-Based Stone: Quartzite/mica schist. 1. Carderock Stone, Tri-State Stone and Building Supply. a. Colors: Blue-gray, brown-gray, gray. C. Stone Coping:: 1. Granite: a. Mesabi, North Carolina Granite. b. Slate: Slate for exterior applications. a. Match stone on new building applications D. Concrete Materials 1. Portland Cement: ASTM C 150, Type I/II, gray. 2. Aggregates: Normal weight. 3. Admixtures: Air entraining. E. Concrete Mixtures 1. Normal-Weight Concrete: Compressive Strength (28 days): Minimum 24.1 MPa (35 psi).. 2. Mixing: Ready-mixed. F. Concrete Masonry Units (CMUs): Normal weight. G. Steel Reinforcement: Reinforcing Bars: Deformed steel. H. Veneer Ties and Anchors: Hot-dip galvanized steel. 1. Corrugated metal ties. 2. Adjustable anchors for connecting to concrete. I. Asphalt damp proofing for concrete backup. J. Weep Holes: vinyl weep holes/vents. K. Mortar: Mortar cement. 1. Pigmented mortar for exposed mortar joints. L. Stone Fabrication: 1. Thickness for Anchored Stone Masonry: 150 mm (6 inches). 2. Finish: Match U.S. Coast Guard Headquarters Building. 3. Finish for Copings: Match stone on new building applications.

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1.4 Installation A. Brick Bond Pattern: Running bond. 1. Match existing building masonry coursing, bonding, color and texture. B. Stone Pattern: 1. Split-bed, random-range ashlar with random course heights and random lengths (interrupted coursed). C. Joints: 1. Minimum Width: 6 mm (1/4 inch). 2. Maximum Width: 13 mm (1/2 inch).. 3. Profile: As indicated. D. Anchored Stone Masonry: 1. Anchored to Concrete: Anchored with corrugated-metal veneer anchors. 2. Space between Anchored Stone Masonry and Backup Construction: Filled with mortar. E. Recycle clean masonry waste as fill material.

Schematic Details: Masonry Site Walls

New Stone Veneer Retaining Wall–Type A N.T.S. Not for Construction

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New Stone Veneer Retaining Wall–TypeB N.T.S. Not for Construction

Elevation

Section Stone Bench with Wood Seat N.T.S. Not for Construction

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Historic Brick Veneer Retaining Wall Repair N.T.S. Not for Construction

New Brick Veneer Seat Wall N.T.S. Not for Construction

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New Brick Veneer Retaining Wall N.T.S. Not for Construction

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New Brick Veneer Screen Wall N.T.S. Not for Construction

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XX

Outline specification: Historic Fountains and Pools

1.1

Summary

A. Fountain basin at South Center Garden Courtyard. B. Ornamental fountain at Oak Courtyard (south of Atkins Building). C. Center pool and water reservoir.

1.2

Quality Assurance

A. Comply with local codes regulating design of ornamental water elements and features. 1. Water Depth: As limited by “pool” category.

1.3 Materials A. General: 1. Operational Systems: Design simple systems and controls for easy use by grounds and maintenance crews. 2. Plumbing System: Design to provide adequate water circulation and water quality to minimize algae growth. In addition, provide: a. Two water supply outlets in basin with sufficient separation to aid water circulation. b. Water overflow drain and bottom drain. c. Water hydrant in basin or in close proximity to basin for maintenance use. 3. Pump: Three phase electrical pump for extended pump life operations. 4. Basin Materials: Suited for application, UV resistant, and readily available 5. Waterproof Coating: Compatible with surface finish and material. 6. Avoid submerged joints requiring waterproof sealants. 7. Coping Finish: Meet or exceed coefficient of friction of 0.8. 8. Locate fountain mechanical equipment in secure location, inaccessible to public. 9. Minimize operational noise. 10. Implement grounding mat at basin perimeter. 11. Utilize grade change in placement of pool equipment to minimize operational energy requirement. 12. Wind Monitor Equipment: To minimize water loss during windy periods. 13. Timer: Time clock for control of hours of operation. B. Fountain basin at South Center Garden Courtyard: 1. Dimensions: 3-M (10-foot) diameter, set at grade with 150-mm (6-inch) coping above grade. 2. Sculptural Element: Multi-tiered cast iron fountain in center of basin. 3. Basin: Concrete with waterproof coating, light color. 4. Coping: Decorative brick set in mortar. 5. lumbing: Submerged pump supplying fountain.

C. Ornamental fountain at Oak Courtyard (south of Atkins Building). continued... S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance 1. Dimensions: 3.4 to 3.7 M (11 to 12 feet) in diameter, set at grade with patterned coping 150 to 200 mm (6 to 8 inches) above grade. 2. Sculptural Element: Multi-tiered cast iron fountain in center of basin. 3. Basin: Concrete with waterproof coating, light color. 4. Coping: Decorative pattern cast iron or lead coping, light color, painted egg and dart pattern. 5. Plumbing: Submerged pump supplying fountain.

D. Center pool and water reservoir. 1. Dimensions: 15 M (50 feet) in diameter. 2. Basin: Concrete with waterstops in joints, or liner. 3. Coping: Stone or brick with mortar joints, set at grade with coping above grade. 4. Plumbing and Filtration: Designed to maintain water circulation for water quality including removal of biological and organic waste and small particles. 5. Fencing: Iron perimeter fence for safety.

1.4 Installation A. Basin: Bottom slope to drain for cleaning and winterizing. B. Match existing masonry coursing and bonding.

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Schematic Details: Historic Fountains and Pools

Fountain at Oak Courtyard N.T.S. Not for Construction

Plan

Section Small Fountain Basin at South Center Garden Courtyard N.T.S. Details by Heritage Landscapes

Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

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XX

Outline specification: Site Furnishings

1.1

Summary

A. Benches, historic and new. B. Trash receptacles. C.

1.2 A.

Bollards.

Quality Assurance Mock-ups

1.3 Benches A.

Historic Benches: 1. Frame: Steel bars, welded and bolted. 2. Seat and Back: FSC certified wood, formed into evenly space parallel slats. 3. Finish: a. Metal: Painted black. b. Wood: S4S. 4. Installation Method: Free standing.

B.

New Benches: 1. Frame: Cast ductile iron. 2. Seat and Back: Black locust, or as indicated, formed into evenly spaced parallel slats. 3. Finish: a. Metal: Baked-enamel, powder-coat, black. b. Wood: S4S.

4.

Installation Method: Surface mounted.

1.4 Trash Receptacles A.

To be coordinated with GSA.

1.5 Bollards

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A.

Steel pipe.

B.

Finish: Painted black.

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Schematic Details: Site Furniture

Historic Bench

N.T.S. Detail by Heritage Landscapes Details provided for intent of design materials and construction methodology. They are not for construction. Details to be reviewed and approved by GSA.

New Bench

N.T.S. Not for Construction

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Trash Receptacle Anchor N.T.S. Not for Construction

Light Pole Foundation N.T.S. Not for Construction

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Metal Bollard

N.T.S. Not for Construction

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Bus Shelter

N.T.S. Not for Construction This is a custom design. No outline specification is provided.

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XX

Outline specification: Exterior Lighting (excludes Security Lighting)

1.1

Quality Assurance:

A.

Quality Standard: AASHTO LTS-4-M.

1.2 Warranty: A.

Materials and Workmanship for Luminaires: 5 years.

B.

Poles and Mast Arms Metal Corrosion: 5 years.

C.

Poles and Mast Arms Color Retention: 5 years.

D.

Finish, Materials, and Workmanship for Poles: 5 years.

1.3 Products A.

Luminaire Finishes: Manufacturer’s standard finish 1. Steel Luminaires: Factory-painted, polyurethane enamel. 2. Aluminum Luminaires: Factory painted finish.

B.

Photoelectric Relays: Single throw, factory mounted to luminaire.

C.

Fluorescent Ballasts and Lamps: Suitable for low-temperature environments. 1. Ballasts for low-temperature environments. 2. Ballast Characteristics: a. Power Factor: 90 percent, minimum. b. Sound Rating: Class ‘A’. c. Total Harmonic Distortion Rating: Less than 10 percent. d. Electromagnetic Ballasts: Energy-saving, high power factor, Class P, automatic-reset thermal protection. e. Case Temperature for Compact Lamp Ballasts: 65 deg C, maximum. f. Transient-Voltage Protection: Category A or better. 3. Low-Temperature Lamp Capability: -29 degrees C (-20 degrees F) and higher.

D.

HID Lamp Ballasts: Constant-wattage autotransformer or regulating high-power-factor type and suitable for low-temperature starting. 1. Auxiliary, instant-on, quartz system. 2. High-pressure sodium ballasts.

E.

HID Lamps: Phillips Cosmo White lamps.

F.

Steel Poles: XF1. 1. Base: DWBUSC-17-TBD; ductile US Coast Guard Base, 432-mm (17-inch) diameter. 2. Shaft: SSH2F-G11-7.5-29-TN4.5/8.75-136/2NW-TBD steel shaft, 12 flat flute, 11 gauge, 190-mm (7-1/2inch) diameter, 8.84 M (29 feet) tall.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance 3. Pole Tenon: 114 by 223 mm (4-1/2 by 8-3/4 inches). 4. Cross Arm: AARBCC-1S-29-36-TN/-TBD aluminum Bishops Crook Arm, single, 738-mm (29-inch) bend diameter, 915-mm (36-inch) rise, 51-mm (2-inch) threaded tenon. 5. Finish: Factory painted. G.

Steel Poles: XF2. 1. Base: DWBUSC-17-TBD; ductile US Coast Guard Base, 432-mm (17-inch) diameter. 2. Shaft: SSH2F-G11-7.5-29-TN3.5/7-136/2NW-TBD steel shaft, 12 flat flute, 11 gauge, 190-mm (7-1/2-inch) diameter, 8.84 M (29 feet) tall. 3. Pole Tenon: 89 by 178 mm (3-1/2 by 7 inches). 4. Cross Arm: AARMIA-1S-72-48-TN2.375/6-TBD aluminum Miami arm, single, 1830-mm (72-inch) long, 1220-mm (48-inch) rise, 50-mm (2-inch) Schedule 40 pipe tenon 152 mm (6 inches) long. 5. Finish: Factory painted.

H.

Steel Poles: XF2a. 1. Base: DWBUSC-17-TBD; ductile US Coast Guard Base, 432-mm (17-inch) diameter. 2. Shaft: SSH2F-G11-7.5-29-TN3.5/7-136/2NW-TBD steel shaft, 12 flat flute, 11 gauge, 190-mm (7-1/2inch) diameter, 8.84 M (29 feet) tall. 3. Pole Tenon: 89 by 178 mm (3-1/2 by 7 inches). 4. Cross arm: AARMIA-1S-72-48-TN2.375/6-TBD aluminum Miami arm, single, 1830-mm (72-inch) long, 1220-mm (48-inch) rise, 50-mm (2-inch) Schedule 40 pipe tenon 152 mm (6 inches) long. 5. Finish: Factory painted.

I.

Steel Poles: XF2b. 1. Base: DWBUSC-17-TBD; ductile US Coast Guard Base, 432-mm (17-inch) diameter. 2. Shaft: SSH2F-G11-7.5-29-TN3.5/7-(2)BN-136/2NW-TBD steel shaft, 12 flat flute, 11 gauge, 190-mm (7-1/2- inch) diameter, 8.84 M (29 feet) tall 3. Pole Tenon: 89 by 178 mm (3-1/2 by 7 inches). 4. Cross Arm: AARMIA-1S-72-48-TN2.375/6-TBD aluminum Miami arm, single, 1830-mm (72-inch) long, 1220-mm (48-inch) rise, 50-mm (2-inch) Schedule 40 pipe tenon 152 mm (6 inches) long. 5. Finish: Factory painted.

J.

Steel Poles: XF3. 1. Base: DWBUSC-17-TBD; ductile US Coast Guard Base, 432-mm (17-inch) diameter. 2. Shaft: SSH2F-G11-7.5-18-TN3.5/3-323/2NW-TBD steel shaft, 12 flat flute, 11 gauge, 190-mm (7-1/2inch) diameter, 5.49 M (18 feet) tall. 3. Pole tenon: 89 by 76 mm (3-1/2 by 3 inches). 4. Finish: Factory painted.

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Pole Accessories: 1.

Breakaway supports.

2.

Duplex receptacle.

3.

Base covers.

4.

Transformer base.

5.

Banner arms.

6.

Flag holders.

7.

Ladder rests.

8.

Lowering system for luminaires.

Schematic Details: Exterior Lighting

Pier Mount Light (XF4) Lighting: Luminaire Family N.T.S. Not for Construction

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Historic Pole Light (XF1)

Roadway Pole Light (XF2)

Lighting: Luminaire Family N.T.S. Not for Construction

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Pedestrian Path Pole Light (XF3)


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Stormwater Management Details for the St. Elizabeths West Campus It is essential to the success of the landscape design, restoration and stormwater management strategies proposed for the St. Elizabeths Campus to understanding the site’s hydrology and how it will be impacted during and after construction. Management of stormwater during construction will include the protection of both soil and vegetation, proper storage of construction materials, removal of construction waste, the preservation of plant and animal habitat and the defense of the natural drainage system, wherever possible—both above and below ground. This section includes an overview of stormwater management techniques including outline specifications and schematic details.

XX

Outline specification: Rock Work

1.1

Summary

Rock Work The use of a natural material such as stone to help manage, convey and dissipate the energy of stormwater runoff can help control soil erosion and reinforce the site’s natural drainage ways. The majority of the proposed rock work will occur in the ravine to the north of Sweetgum Lane. This area has some of the highest quality forest on the campus and an active, stream that flows most, but not all, of the year. The contractor must read and understand the concepts discussed in the Site Protection section of this chapter, prior to starting any work in this area. Key strategies for protecting the site’s drainage-ways during construction include: •

Control of stormwater discharge into drainage ways

Dissipation of energy from stormwater by building check-dams and stepped pools

Storage of construction materials on the existing Sweetgum Lane roadbed

Enter the ravine only from the bridge crossing, to prevent damage to the steep side slopes

Use small cranes placed on the roadway to lower material into the ravine. Protect all existing trees during this operation.

A. River stone swales B. Boulders C. Stone drip strips D. Step-pool

1.2 Materials A. Round River Stone: 1. Natural, local, riverbed stone a. Sizes as indicated B. Boulders: 1. Natural, rounded stone a. Sizes as indicated 2. Imported boulders: Range of sizes, minimum 610 mm (24 inches), maximum 1520 mm (60 inches) in any direction.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance C. Coir Fabric D. Geotextile E. HDPE pipe wrapped in nonwoven geotextile, size as indicated. F. EPDM Liner G. Drainage Stone: 1. Size: 19-mm (¾-inch) washed crushed stone.

1.3 Installation A. River Stone Swale - Installation of Coir Fabrics 1. Place fabric and overlap edges by 305 mm (12 inches) minimum. 2. Secure fabric on sides of swale and perimeters by burying where indicated, and anchor with wood stakes 305 mm (12 inches) on center along sides. 3. Anchor throughout with wood stakes spaced 610 mm (24 inches) on center. Anchor overlaps with stakes 305 mm (12 inches) on center. 4. Comply with “Plantings” for fabric log planting instructions B. River Stone Swale 1. Install river stone on EPDM liner, complying with liner manufacturer’s written instructions for protection of EPDM liner. C. Boulders 1. Installation of boulders along swale: a. Place boulders by general size and in locations indicated before installing rocks. b. Press into fabric and soil c. Spread river stone in sizes and mix in proportions indicated 2. Installation of Stone Check Dam: a. Place boulders by general size and in locations indicated before installing rocks b. Press into fabric and soil c. Fill chinks in check dam with cobbles. d. Boulders: Combination of reused stone from the site and local stone. f. Check dams stabilized and anchored with geogrid D. Drip Strip 1. Place woven geotextile over prepared subgrade 2. Install drainage stone and HDPE pipe 3. Install flush granite edge 4. Install river stone or gravel to depth indicated.

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Schematic Details: Rock Work

Typical Step-Pool Section N.T.S. Not for Construction

Typical Step-Pool Plan N.T.S. Not for Construction

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Stone Drip Strip N.T.S. Not for Construction

Typical Check Dam N.T.S. Not for Construction

Typical Stone Swale N.T.S. Not for Construction

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Fiber logs Care must be taken to stabilize any bare slope around newly created water features or stormwater management BMPs. “Fiber logs” are the method of choice to stabilize the banks of a stream or pond. Fiber logs are a roll of “coir” fiber (a by-product of coconut husks) that is flexible and can be anchored with stakes into the curving banks of ponds and streams. They provide both a temporary “erosion blanket” and a stable medium for plants to grow in. Plugs of herbaceous plants can be set directly into the rolled material (log) Over a period of time (3-5 years) the coir material will rot away. As long as the plants are kept wet, they will quickly root in the coir medium and grow into the banks, providing permanent stabilization of the channel sides.

XX

Outline specification: Fiber Logs

1.1

Summary

A. Stream Restoration B. Swales

1.2 Materials A. Fiber Logs: 300mm (12 inch) diameter coir rolls, 7 pounds/cubic foot, with coir twine outer net. B. Coir Twine: coir twine, 8.9mm (0.35 inch) diameter, 65 – 90 pound strength. C. Wood Stakes: 50mm x 50mm (2 x 2 inches), 450mm (18 inches) long, with pencil-point end and notch cut in one side of stake.

1.3 Installation A. Place coir rolls on prepared subgrade as shown. Review layout with Landscape Architect. B. Tie ends of adjacent rolls together with coir twine. Use extra loops of coir twine through outer netting of adjacent coir tolls. C. Install wood stakes through fiber log at spacing shown. D. Place ends of fiber logs toward channel bank and bury. Secure with wood stake and coir twine

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Plan

Section Coir Log Erosion Control at Stream Channel N.T.S. Not for Construction

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Stormwater Cistern The cisterns proposed for the St.Elizabeths campus are subsurface storage tanks designed to capture and store stormwater from building roofs. Stormwater that is harvested and collected in these cisterns will be used for irrigation and within certain buildings, for toilet flushing. To allow excess stormwater to infiltrate into the soil the cisterns are placed over stormwater recharge beds. (The construction of these beds are discussed in greater detail later in this chapter). Guidelines for the excavation and placement of these cisterns are detailed in the Site Protection section of this chapter.

XX

Outline specification: Stormwater Cistern

1.1

Summary A underground stormwater storage cistern with geomembrane liners.

1.2 Materials A. General: Provide impervious geomembrane liner fabricated from sheet material indicated and complying with specified product characteristics. B. EPDM Sheet: Formulated from EPDM, compounded for use in hydraulic structures and to permit heat-welded seams, and formed into uniform, flexible sheets. C. Stormwater Cistern: Manufactured structural, modular units or precast concrete or HDPE precast structure designed for providing underground storage of storm water.

1.3 Quality Assurance A. Preinstallation Conference: Conduct conference at Project site to comply with requirements in Division 1 Section “Project Management and Coordination.”

1.4 Installation A. Install stormwater cistern units according to manufacturer’s written instructions. B. Place HDPE sections as indicated on Drawings. C. Install sand setting bed. D. Install protection layer of geotextile fabric on sand setting bed. Overlap seams according to manufacturer’s written instructions.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance E. Install geomembrane liner over protection layer F. Install layer of geotextile fabric over geomembrane liner and around entire stormwater cistern. Overlap seams according to manufacturer’s written instructions. Provide for continuous sump on low side of cistern. G. Attach pipe inlets and outlets. H. Install folded strips of geotextile fabric on corners of stormwater cistern and secure temporarily. I. Enclose stormwater cistern with geomembrane liner and geotextile fabric.

Schematic Details: Cisterns

Cistern–Section N.T.S. Not for Construction

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Porous Asphalt Paving Porous or permeable paving is a no-fines asphalt that allows water to percolate through its surface. Laid in a single 50mm (2 inch) lift it is part of a larger system and depends, most importantly, on it being understood as a coordinated unit—both paved surface and recharge basin working together as a system. The multi-use trail that runs parallel to the West Access Road will be constructed of permeable asphalt paving. The permeable paving will allow rain water and snow melt to seep into the tree trench located below the paving. paved trail. The system must meet several important criteria—both during and after construction. If any of these requirements are not properly adhered to, the system will fail. •

Experienced installers must be used

The infiltration capacity of the existing soils must be tested.

The ambient air temperature must not fall below 55 degrees Fahrenheit during installation and setting.

Porous paving cannot be placed when the surface is wet

The aggregate sub-base must be properly compacted and tested .

The large stones that fill the recharge basin must be clean and uniformly graded and provide approximately 40% void space.

Clean and vacuum up any dirt or debris that falls on the permeable surface.

XX

Outline specification: Porous Asphalt Paving

1.1

Summary

A. Porous hot-mix asphalt paving B. Choker course

1.1

Quality Assurance

A.

Manufacturer Qualifications: A qualified manufacturer.

B.

Testing Agency Qualifications: Qualified according to ASTM D 3666 for testing indicated, as documented according to ASTM E 548.

continued...

S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance C.

Regulatory Requirements: Comply with the following: 1. District Department of Transportation specifications for asphalt paving work. 2. Standards of the American Association of State Highway and Transportation Officials (AASHTO).

D.

Asphalt-Paving Publication: AI MS-22, “Construction of Hot Mix Asphalt Pavements,” unless more stringent requirements are indicated.

1.2 Materials A. Aggregates for Asphalt Pavement: DOT plant-mix. 1. Aggregate Gradation:

U.S. Standard Sieve Size

2. B.

Percent Passing

12.5-mm (½-inch) 9.5-mm (3/8-inch) 4.75-mm (No. 4) 2.36-mm (No. 8) 1.18-mm (No. 16) 600-µm (No.30) 75 µm (No. 200)

100 92-98 32-38 12-18 7-13 0-5 0-3

½” (12.5mm)

100

Hydrated Lime: ASTM C 977.

Asphalt Materials: 1. Asphalt binder modified with elastomeric polymer to produce a binder meeting the requirements of Performance Graded Binder 76-22. 2. Water: Potable.

C.

Asphalt Mixes: 1. Hot-laid, porous hot-mix asphalt plant mixes complying with the following requirements: a. History of satisfactory performance in geographical area where Project is located. b. Bituminous Content: 5.5 to 6.0 percent by weight (dry aggregate). c. Binder Draindown: ASTM D 6390, maximum of 0.3 percent.

D.

Aggregate Choker Course: AASHTO Number 57.

1.3 Installation A.

Choker Course: Choker course over infiltration bed and geotextile.

B.

Edge restraints as indicated.

C.

Porous Hot-Mix Asphalt Paving: 1. Base Course: Thickness as indicated.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance 2. Surface Course: Thickness as indicted, single lift. D.

Joints: Unsealed.

E.

Compaction: One to two passes only to maintain surface porosity.

1.4 Maintenance and Protection A.

Sediment control fabric along edges of porous pavement adjacent to areas of bare soil.

1.5 Field Quality Control A.

Testing Agency: Owner engaged. 1. Permeability of pavement surface.

XX

Outline specification: Porous Concrete Paving (to be added)

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Schematic Details: Porous Paving

Porous Asphalt Pavement N.T.S. Not for Construction

Porous Concrete Pavement N.T.S. Not for Construction

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Stormwater Recharge Beds Recharge beds are an essential part of several major stormwater management strategies on the St. Elizabeths campus. Recharge beds are underground storage basins that temporarily store stormwater and slowly release it to the water table to recharge ground water. At St. Elizabeth’s campus these beds will be installed below roadways, trails and sidewalks that will be constructed on soils that allow infiltration. Installing recharge beds in areas that will be disturbed during construction, limits the over all amount of disturbance on campus. These areas also conserve usable space on the site by performing multiple functions—for example, the recharge bed also serves as the sub-base for the roadway. These subsurface systems will allow the GSA to meet the stringent federal and state stormwater requirements, while preserving the essential qualities of this historic landmark. The success of a recharge basin system depends on meeting several important criteria both during and after construction. If any of these requirements are not properly adhered to, the system will fail.

Existing soils must be tested to determine their ability to infiltrate stormwater

The subsoil must not be compacted during construction

A conventional overflow system connected to the stormwater drainage pipes on campus, must be provided as a backup.

Water must be able to percolate through the an infiltration trench within a 24 hour period

Access must be provided to these underground systems for monitoring and periodic cleaning

XX

Outline specification: (see Soil Spec.)

Schematic Details: Infiltration Trenches

Infiltration Trench N.T.S. Not for Construction

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Vegetated Swales

Schematic Details: Swales

Vegetated swales are broad, shallow channels planted with native vegetation covering the side slopes and also occasionally the bottom of the channel. Swales are primarily designed to slow the flow across the land. They also clean the water of both sediments and pollutants. The roots of the plants trap sediments. A meandering channel, plus the plant roots and tops will also slow the velocity of the water. The slower the water flows, the more time for it to infiltrate into the soil, often through the channels made by plant roots. The microscopic life on the plants working in concert with the chemicals of the plants themselves can break down a wide variety of pollutants. At St. Elizabeths, vegetated swales are used primarily on the sloping areas of the site. Drainage on the plateau should use grass swales to preserve the quality of the historic “shadow lawn.” Key considerations during construction include: The success of a vegetated swale depends on meeting several important criteria both during and after construction. •

Testing the capacity of the existing soils to infiltrate stormwater

Grade the side slopes at 1:10.

Stabilize he entire swale with jute netting to prevent erosion

If the swale has a steep grade, stabilize the bottom with river stones and occasional boulders

Use sods of both grasses and wetland wildflowers, instead of seed, to reduce loss of seed from washouts

Cut swale vegetation in late November, to present a neat appearance in winter.

Outline specification: (see Plant Spec.)

Grass Swale

N.T.S. Not for Construction

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Vegetated Swale N.T.S. Not for Construction


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Construction Guidance

Tree Trench Tree trenches are long, linear planting beds that replace the single, isolated tree pit, along a street. Tree trenches allow for better root development for the a line of trees. The continuous trench, covered with a modular material, or with grass or ground covers, encourages rainwater and snow melt to soak into the soil. With the addition of a specially designed soil mix, tree trenches will can function much like an infiltration trench or rain garden.. The success of a tree trench depends on meeting several important criteria both during and after construction. •

Testing the existing soils capacity to infiltrate stormwater

The use of a rigid, vertical support system such as “Silva Cell”

Proper soil design mix to infiltrate water and also to allow encourage adequate root development

Installation of a back up, overflow system to convey excess water out of the trench when necessary.

Access to for monitoring and periodic maintenance.

Road salts and periodically inundated soils will require specially tolerant plant material to handle these specialized conditions

XX

Outline specification: (see Structural Soil Spec.)

Schematic Details: Tree Trenches

Tree Trench

N.T.S. Not for Construction

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Infiltration Basins/Rain Gardens A rain garden is a small depression sited at a low point and used to capture and infiltrate stormwater runoff. Infiltration basins and rain gardens will be limited to the new courtyards in phases 1 and 3 and in certain locations within the forests and ravines of the campus. The placement of these systems within the existing landscape should be carefully decided. The contractor should review the criteria outlined in the Site Protection section of this chapter. The success of a rain garden depends on meeting several important criteria both during and after construction. • Testing the existing soils capacity to infiltrate stormwater •

A special soil mix designed to support infiltration and the wetland plantings.

Choose appropriate, tough plants that can handle these specialized conditions (i.e. occasional drought as well as periodically inundated soils)

Rain Garden

N.T.S. Not for Construction

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XX

Outline specification: (see Soil Spec.)


CHAPTER V

S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n

g

Schematic Design Concepts

CHAPTER 5

Schematic Design Concepts

Introduction This chapter presents conceptual designs for key areas of the campus landscape. These sites were chosen because they illustrate the integration of historic and modern landscape elements with required management goals. These goals include tree and forest preservation, stormwater management, soil preservation and remediation, pedestrian and vehicular circulation, parking and service access, and preservation of historic character. Some conceptual designs illustrate specific coordination issues, such as the integration of utility design and tree preservation. Other designs illustrate a vocabulary that addresses both the historic and environmental components of the campus. This vocabulary is provided as a reference for the design teams.

Site Utilities Coordination and Preservation of Historic Trees The coordination of planned utilities with the protection of historic trees is a critical and time-sensitive issue, which affects site servicing options and the construction budget for various projects. For this reason, the preliminary utility designs were mapped in conjunction with the existing tree assessment. Based on this mapping, utilities routes were modified to avoid trees where possible. Where re-routing was not possible, sustainable construction techniques compatible with tree preservation, such as tunneling, are recommended; .see Fig 60 Site Utilities Coordination and Historic Tree Protection, page 258 Tree preservation must continue to be incorporated into utility design for subsequent phases of each project. Each project should include: consideration of low-impact routes, appropriate construction methods, pre-construction care for affected trees, and post-construction tree care and monitoring. Chapter III details a conceptual approach to tree protection and Chapter IV provides specific tree protection techniques.

Schematic Design Concepts Four specific areas were selected as being representative of the various landscape conditions at St. Elizabeths. These concepts illustrate potential starting points for historically appropriate, integrated landscape design: •

Re-introduction of the historic Center Building Pond

Rehabilitation of the Sweetgum Ravine

Re-establishment of the woods at the Burroughs Cottage Ravine

Provision of recreational trails adjacent to Sweetgum Lane and the historic Holly Grove.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Schematic Design Concepts

Center Building Pond

Sweetgum Lane Ravine

Landscape interventions which accommodate new functions and renovate or replace degraded or missing landscape features strengthen the historic character of the campus. Although not a requirement of the Landscape Preservation Plan, if a lost element is important for strengthening the overall experience of the campus, that element may be reintroduced. The former pond south of the Center Building is an excellent example of a missing feature that if recaptured will greatly enhance the landscape experience.

The Sweetgum Lane ravine is a major drainage feature on the St. Elizabeths campus. Over time, however, increases in water volume entering the ravine have lead to severe erosion, scouring, and degradation of the channel and of the riparian plant community. Three zones of intervention have been indentified where various restoration techniques can be utilized to return the ravine to a healthy, functioning state:

The proposed schematic design replicates the approximate size and location of the historic pond. It enhances the pond edge with a perimeter walk and locations for seating. Path connections are made to the Center Building and to surrounding historic walks and roadways. Existing historic trees should be preserved where possible. The 2016 Landscape Preservation Plan should be referenced for approximate locations of historic 1937 trees to be replanted. The schematic design also illustrates a proposed location for a fire lane and turn around area to the south of the Center Building. While no roadway was present in the period of significance, current code requires a fire lane for this building. This fire lane could be incorporated into the surrounding landscape spaces and be used as an additional outdoor plaza.

Zone 1 – Pipe “Daylighting” – Currently, the upper portion of the stream is piped. Removing the pipe between the current outfall and the edge of the plateau, and restoring the stream channel (daylighting) could increase the stormwater retention capacity of the ravine. The extension of the stream up to the edge of the plateau can also provide an additional landscape feature visible from Sweetgum Lane and Golden Raintree Drive. Zone 2 – Riparian Corridor Restoration – The current riparian corridor extending from the pipe outfall to the wetland at the bottom of the ravine exhibits severely eroded and degraded banks. Bank stabilization techniques (detailed in Chapter IV) and the reintroduction of a network of weirs will reduce conveyance rates through the channel, mitigate erosion and allow the reestablishment of native vegetation. The sloped lawn at the Point generates large amounts of sheet flow. Widening the riparian buffer by reclaiming what is presently lawn would slow stormwater velocity, reduce runoff volume and filter the sediment it carries. The meadow cover proposed for the lower slopes will help address these stormwater concerns. Zone 3 – Wetland Restoration – Zone 3 is a delineated wetland. Appropriate restoration techniques should be used to repair channel erosion and stabilize the stream banks. Invasive plant species should be removed and this wetland re-planted with the appropriate native vegetation.

Cropped 1948 aerial showing historic pond —Courtesy Heritage Landscape, etc.

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Schematic Design Concepts Sweetgum Lane Riparian Corridor

Zone 2: Degraded conditions along the stream channel in teh Sweetgum Ravine

The sloped lawn below the point gtenerates large amount of runoff. The proposed conversion of the lower lwan to meadow will help address stormwater concerns and protect the stream. Lawn in the foreground, close to the drive, would remain as mown turf.

Wetland at the lower ravine

Eroded stream banks along the lower section of the stream

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Schematic Design Concepts

Burroughs Cottage Ravine As shown in the 1947 topographic survey and the 1948 aerial, the northern side of Borroughs Cottage originally faced a ravine. The ravine has since been filled in (see 1966 aerial). The schematic design for this area introduces a shallow wetland to capture stormwater. This water feature at the bottom of the slope is excavated to intercept an existing spring (now buried). It is treated as a wooded wetland of black gum and sweetbay magnolia. A small fern meadow captures the water and sediment at the top of the slope. These two depressions are connected by a meandering swale of tall grasses and wildflowers punctuated by small flowering trees. The existing trees should be preserved and supplemented with additional trees, as illustrated in the 2016 Plan.

1948 aerial with 1947 topographic survey overlay. Mapping provided by Heritage Landscapes.

1966 aerial photograph with topogragphic survey overlay. Mapping provided by Heritage Landscapes.

Sweetgum Lane Trails and New Road Alignment The historic Sweetgum Lane is not adequate to meet the needs of the modern St. Elizabeths campus. Many delivery, emergency, and construction vehicles are unable to navigate the slope or the alignment of the current road. A new alignment proposed by the civil engineer (WHGA) is incorporated into the new plan leaving the historic Sweetgum Lane to become part of an expanded pedestrian network that includes jogging trails and security paths. Similarly, remnant and existing gravel roads from the period of significance should also be incorporated into this trail network. The materials used for both the historic and proposed trails will be the same. Slight variations in aggregate size, or trail markers, can be used to distinguish between historic and modern alignments. Detention basins and vegetated swales will take and hold stormwater from the new road alignment, gradually releasing it into the Sweetgum Lane Ravine.

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CHAPTER IV

S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n

g

Sustainability Rating Systems

CHAPTER 6

Sustainability Rating Systems

Introduction The GSA has a long standing goal to integrate sustainable design performance requirements into all new construction projects. In October 2009, President Obama signed Executive Order 13514, mandating significant reductions in greenhouse gas emissions as well as other government standards for a sustainable project. The GSA goal, combined with the new federal mandate, has suggested the use of two different, but complementary rating systems to help the St.. Elizabeths project integrate basic ecological principles into contemporary design, construction and operation methods, and to protect, enhance and restore the natural resources of the site. These programs include: the rating system for Green Building, known as LEED® (Leadership in Energy and Environmental Design) and SITES™ (formerly called the Sustainable Sites Initiative, currently launching its Pilot Program). SITES™ significantly extends the focus of a “green rating system”, beyond the building envelope, into the surrounding landscape.

Leed® In the early 1990s, the Natural Resources Defense Council led a broad-based coalition to develop LEED®. Now administered by the United States Green Building Council (USGBC), this program was initiated to encourage sustainable building and development practices, through easily understood and widely acceptable tools. It is a third-party certification program and a nationally and internationally accepted benchmark, which rewards the use of practical, measurable strategies that improve performance for water efficiency, energy savings, indoor environmental quality, CO2 emissions and the reduction of impacts to the landscape. A majority of LEED® credits are tied to environmental performance goals within a building. The USBGC recognizes that there is more work to do with LEED® to improve the site components. It has recently extended LEED® programs beyond the building footprint, into the surrounding neighborhood with the LEED® for Neighborhood Development rating system. This program focuses on appropriate location and community pattern—where people live and work and how they move around.

Sites™ SITES™ is a recent program, the result of collaboration between the American Society of Landscape Architects, the Lady Bird Johnson Wildflower Center and the United States Botanic Garden. It is a series of voluntary national guidelines and performance benchmarks for sustainable land design, construction and maintenance practices. LEED® and LEED® for Neighborhood Development have a number of parallels to SITES™. These programs significantly extend the focus of sustainable design beyond the building envelope. SITES™, however, focuses on the site scale (regardless of size) and the ways in which people maintain, protect and restore ecosystem services—clean air and water, climate and habitat protection and the restoration of natural system functions. Its goal is to transform land development and land management practices and to go beyond site conservation and require site improvements that also regenerate “ecosystem services.” SITES™ requires the incorporation of fundamental ecological principles into modern design, construction and operation methods. It supports the protection, enhancement and restoration of the natural resources of a site. SITES™ is intended to influence planners, architects, engineers, designers, curators, contractors and maintenance workers, as they create and maintain outdoor spaces. Both systems are intended to provide guidance on Best Management Practices S e n s i t i v e B u t U n c l a ss i f i e d

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S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Sustainability Rating Systems (BMPs) and to measure the benefits of a sustainable project on its landscape. The SITES™ structure is deliberately similar to LEED®, and SITES™ is specifically written to be compatible with the Sustainable Sites (SS) category of the LEED® rating system. It will probably be incorporated into future versions of LEED®. SITES™, a relatively new system, is about to begin a Pilot Program. The plan for the St.. Elizabeths campus has been suggested as one of the demonstration projects that will illustrate and evaluate the first version of this system. The United States is under increasing pressure, domestic and international, to set an example for strong, long-term measures to reduce climate change and environmental degradation and to make wiser use of the world’s resources. The St.. Elizabeth project, given its size, its historic status and the fact that it is a GSA project, positions it strategically to be a model for future development in this country.

Approach An integrated process characterizes the approach for St.. Elizabeths West Campus plan. The LEED® and SITES™ rating systems, require the design team (made up of consultants from many different disciplines), to work together and to provide a logical, functional and coherent framework for the many different facets of the project. These standards are also intended to help restore the campus to an ecologically healthy and culturally rich place, as well as to streamline construction activities and prevent waste. The approach to the St.. Elizabeths plan is significantly different from the general applications of LEED®. Selected credits will be documented on a site-wide scale using the LEED® 2009 (v 3.0) rating system. and include credits that need quantification on a campus-wide scale early in the design phase. Documenting credits on a site-wide scale offers efficiencies, both for the design team and the administrators of the LEED® and SITES™ programs. For example, Sustainable Sites Credit 5.1—Protect or Restore Habitat—requires that specific guidelines be in-place for the successive design teams to follow during the design of individual projects within the campus. Other credits, such as Sustainable Sites Credit 6.1 and 6.2—Stormwater Design, Quantity and Quality—may require additional documentation during future projects to comply with the intent of the credit. The remaining credits will be documented for each specific building project, under LEED® 2009 with the exception of the US Coast Guard Headquarters (documentation under LEED® v2.2).

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Process and Credits All projects, excluding the US Coast Guard Headquarters, at St.. Elizabeths will use the LEED® 2009 guidelines. Projects will be rated on a point system, awarding points for credits in different categories such as Site Selection, Hydrology, Materials and Resources, Indoor Environmental Quality and Operations and Maintenance. Projects receiving points above pre-defined benchmarks are awarded one of four certifications: for LEED®, Silver, Gold and the highest rating is Platinum; for SITES™, One, Two, Three and the highest rating is Four Stars.

Pre-design Both the LEED® and SITES™ process should begin almost immediately after the project is launched. To ensure the success of the process and the project, the entire design team must be involved from the beginning. The benefits of the integrated design process can easily be lost if all parties are not included. Both rating systems should be discussed during initial client and stakeholder programming and site selection. The team should establish their credit goals at this time. SITES™ has an entire category of prerequisites and credits dedicated to “Pre-Design Assessment and Planning.” The purpose of this requirement is to lay the framework for design, construction and future operations. The design team is required to assess the site, its opportunities and constraints and discuss how each discipline can inform the design and eventual use and operation of the site. SITES™ also requires that an integrated design team be chosen that has expertise in the design, construction and maintenance of sustainable projects. SITES™ encourages the design team to engage stakeholders and users of the site in a meaningful way to inform site programs. SITES™ also mandates construction oversight (in addition to the contractor) and a maintenance plan to ensure future performance. PREREQUISITES, REGISTRATION and INITIAL CREDIT CALCULATIONS: One of the first steps in implementing both rating systems is to determine whether the project can meet the prerequisites. Please refer to the LEED® Reference Guide for Green Building Design and Construction, 2009 Edition and the Sustainable Sites Initiative: Guidelines and Performance Benchmarks 2009 for specific requirements.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Sustainability Rating Systems Once it has been determined that the project can meet the all the required prerequisites, the project is registered with the Green Building Certification Institute (GBCI) on the LEED® Online website. This website provides all the tools necessary for tracking and administering the LEED® process and collaborating with the design team. All credit documentation should be submitted electronically through this website. Project registration for SITES™ takes place on the SITES™ website. Since SITES™ is newly launched, methods of registration and administration may change in the future. After registration, the design team begins to collect information and calculates the initial credits, to determine whether they can be feasibly obtained. DESIGN: During the design phase, credit calculations should be revised at specific milestones to check the status of anticipated compliance and to keep sight of the project’s initial goals. LEED® projects can submit a Design Phase Review before construction begins. GBCI will review this credit documentation and offer feedback on potential credit achievement. This Preliminary Review gives the design team guidance on areas needing further study and documentation before final review. CONSTRUCTION: There are certain credits in both rating systems, which cannot be documented during the design phases and require information from the construction process. LEED® Materials and Resources Credit 2—Construction Waste Management—requires that the Contractor regularly log the quantities of all construction waste and its disposal. The contractor must document the percentage of waste diverted from a landfill. At the end of the construction process, the team will submit all credit documentation. GBCI will make a final review and award or deny the proposed credits.

Progress Scorecard Based on the information and design evolution at the time of printing, the goals for credit achievement are: (see Fig 67 LEED Credit Goals, page 265 and see Fig 68 Sustainable Sites Initiative Credit Goals, page 266 )

Monitoring Performance The site-related credits in LEED® can be completed by the end of the construction phase. However, there are certain Energy and Atmosphere and Environmental Quality credits (mostly related to building systems) that require post-construction monitoring in the months and years following construction. Similarly, SITES™ has two credits that require long-term monitoring of the sustainable design practices implemented in the site design.

S e n s i t i v e B u t U n c l a ss i f i e d

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DRAFT 19 9

overview

Fig 1


DRAFT 200

overview

Fig 2


DRAFT 201

overview

Fig 3


DRAFT 202

overview

Fig 4


DRAFT 203

physiography

Fig 5


DRAFT 204

physiography

Fig 6


DRAFT 205

physiography

Fig 7


Fig 8

soil Pristine Natural Soils

CANDIDATE FOR STAGING AREA

LARGE SCALE PLANTING

EROSION CONCERNS

LEVEL OF PROTECTION

LEVEL OF REHABILITATION NEEDED

Poor

Excellent

Moderate

High

Limited Moderate

Mixed Natural Soils

Poor

Fair

Moderate

Moderate-High

Compacted Natural Soils

Fair

Fair

High

Moderate

Moderate

Gravelly Sandy Loam Fill

Excellent

Poor

Moderate

Low

Replace / Extensive

Compacted Fill

Good

Poor

High

Low

Extensive

Contaminated Fill

Poor

Poor

High

Low

Replace / Cover

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soil

Fig 9


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Fig 10


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soil

Fig 11


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vegetation Fig 12


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vegetation Fig 13


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vegetation Fig 17


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vegetation Fig 18


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vegetation Fig 21


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vegetation Fig 22


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vegetation Fig 24


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vegetation Fig 25


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vegetation Fig 26


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circulation + hardscape

Fig 27


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circulation + hardscape

Fig 28


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circulation + hardscape

Fig 29


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circulation + hardscape

Fig 30


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circulation + hardscape

Fig 31


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circulation + hardscape

Fig 32


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circulation + hardscape

Fig 33


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circulation + hardscape

Fig 34


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circulation + hardscape

Fig 35


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circulation + hardscape

Fig 36


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circulation + hardscape

Fig 37


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circulation + hardscape

Fig 38


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stormwater

Fig 39


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stormwater Fig 40


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stormwater

Fig 41


Fig 42

stormwater Groundwater Investigation- GeoConcepts Engineering

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Fig 43

stormwater Groundwater Investigation- GeoConcepts Engineering

DRAFT 241


GROUNDWATER AND SITE DEVELOPMENT STUDY existing trees on plateau

roots wick water from shallow aquifer

1

stormwater Fig 44

shallow aquifer: approx. 9m below plateau

existing

T UNCLASSIFIED SENSITIVE BUT

ST. ELIZABETHS WEST CAMPUS Groundwater Investigation- GeoConcepts Engineering

10/15/09

DRAFT DRAFT 242


GROUNDWATER AND SITE DEVELOPMENT STUDY existing trees on plateau

excavation of USCG building

roots will lose upper aquifer as a water source

stormwater Fig 45

previous upper aquifer level draw down of aquifer from excavation and dewatering note: depleting the upper aquifer will have a detrimental impact to the existing vegetation

2

construction

T UNCLASSIFIED SENSITIVE BUT

dewatering system

once the water is sent to the storm sewer it will be lost

storm sewer ST. ELIZABETHS WEST CAMPUS Groundwater Investigation- GeoConcepts Engineering

10/15/09

DRAFT DRAFT 243


GROUNDWATER AND SITE DEVELOPMENT STUDY existing trees on plateau

green roof on top of finished USCG building

cistern to releases water for irrigation or for reuse in the building. cistern overflow goes to recharge bed.

overflow of recharge bed out to storm sewer

cistern

pre-treatment

recharge bed

stormwater Fig 46

collected water from dewatering system and cistern overflow slowly released back into groundwater via recharge bed depleted upper aquifer level pump water from the foundation drain / dewatering system recharge bed

3

pump

proposed

T UNCLASSIFIED SENSITIVE BUT

ST. ELIZABETHS WEST CAMPUS Groundwater Investigation- GeoConcepts Engineering

10/15/09

DRAFT DRAFT 244


DRAFT 245

stormwater

Fig 47


DRAFT 246

stormwater Fig 48


DRAFT 247

stormwater Fig 49


DRAFT 248

stormwater Fig 50


DRAFT 249

stormwater

Fig 51


DRAFT 250

phasing

Fig 52


DRAFT 251

phasing

Fig 53


DRAFT 252

phasing

Fig 54


DRAFT 253

phasing

Fig 55


DRAFT 254

phasing

Fig 56


DRAFT 255

phasing

Fig 57


DRAFT 256

phasing

Fig 58


DRAFT 257

phasing

Fig 59


Fig 60

SD

• Individual tree impacts from Phase 3 utility tunneling unknown. • Phase 3 utility tunnels not shown.

DRAFT 258


Fig 61

SD DRAFT 259


Fig 62

SD DRAFT 260


Fig 63

SD DRAFT 2 61


Fig 64

SD DRAFT 262


Fig 65

SD DRAFT 263


Fig 66

SD DRAFT 264


LEED 2009 for New Construction and Major Renovation

St. Elizabeths West Campus

Project Checklist

N

8

Sustainable Sites

Y

Y Prereq 1

1

Credit 1

5 1 6

Credit 2 Credit 3 Credit 4.1 Credit 4.2 Credit 4.3 Credit 4.4

1

Credit 5.1

1 1 1

Credit 5.2 Credit 6.1 Credit 6.2

1

Credit 7.1 Credit 7.2

1

Materials and Resources, Continued

Possible Points: 26

?

Credit 8

Construction Activity Pollution Prevention Site Selection Development Density and Community Connectivity Brownfield Redevelopment Alternative Transportation—Public Transportation Access Alternative Transportation—Bicycle Storage and Changing Rooms Alternative Transportation—Low-Emitting and Fuel-Efficient Vehicles Alternative Transportation—Parking Capacity Site Development—Protect or Restore Habitat Site Development—Maximize Open Space Stormwater Design—Quantity Control Stormwater Design—Quality Control Heat Island Effect—Non-roof Heat Island Effect—Roof Light Pollution Reduction

N

? Credit 4

1 5 1 6 1 3 2 1 1 1 1 1 1 1

Credit 5 Credit 6 Credit 7

2

Water Efficiency

Y Y

Prereq 1 Prereq 2 Credit 1 Credit 2 Credit 3.1 Credit 3.2 Credit 4.1 Credit 4.2

Possible Points: 10

Credit 4.4 Credit 5

Y 4

Prereq 1 Credit 1

2 4

Credit 2 Credit 3

Water Use Reduction—20% Reduction ff d Water Efficient Landscaping Innovative Wastewater Technologies Water Use Reduction

Credit 6.1

2 to 4 2 2 to 4

Credit 6.2 Credit 7.1 Credit 7.2 Credit 8.1

Energy and Atmosphere Y Y Y

Prereq 1 Prereq 2 Prereq 3 Credit 1 Credit 2 Credit 3 Credit 4 Credit 5 Credit 6

Possible Points: 35

Fundamental Commissioning of Building Energy Systems Minimum Energy Performance Fundamental Refrigerant Management Optimize Energy Performance On-Site Renewable Energy Enhanced Commissioning Enhanced Refrigerant Management Measurement and Verification Green Power

Materials and Resources

Credit 8.2

Prereq 1

Credit 1.1

1 to 19 1 to 7 2 2 3 2

Credit 1.2 Credit 1.3 Credit 1.4 Credit 1.5 Credit 2

Credit 1.1 Credit 1.2 Credit 2 Credit 3

Minimum Indoor Air Quality Performance Environmental Tobacco Smoke (ETS) Control Outdoor Air Delivery Monitoring Increased Ventilation Construction IAQ Management Plan—During Construction Construction IAQ Management Plan—Before Occupancy Low-Emitting Materials—Adhesives and Sealants Low-Emitting Materials—Paints and Coatings Low-Emitting Materials—Flooring Systems Low-Emitting Materials—Composite Wood and Agrifiber Products Indoor Chemical and Pollutant Source Control Controllability of Systems—Lighting C ll bili off Systems—Thermal S Th lC f Controllability Comfort Thermal Comfort—Design Thermal Comfort—Verification Daylight and Views—Daylight Daylight and Views—Views

Credit 1.2

1 to 3 1 1 to 2 1 to 2

Innovation in Design: Exemplary SWM performance (???) Innovation in Design: Specific Title Innovation in Design: Specific Title Innovation in Design: Specific Title Innovation in Design: Specific Title LEED Accredited Professional

Credit 1.3 Credit 1.4

18

1 10

Regional Priority: Regional Priority: Regional Priority: Regional Priority:

Specific Specific Specific Specific

1 1 1 1 1 1

Possible Points: 4 Credit Credit Credit Credit

Total Certified 40 to 49 points

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

Possible Points: 6

Regional Priority Credits

Possible Points: 14

Storage and Collection of Recyclables Building Reuse—Maintain Existing Walls, Floors, and Roof Building Reuse—Maintain 50% of Interior Non-Structural Elements Construction Waste Management Materials Reuse

Possible Points: 15

Innovation and Design Process

Credit 1.1

Y

1 to 2 1 to 2 1 1

Indoor Environmental Quality

Credit 4.3

8

Recycled Content Regional Materials Rapidly Renewable Materials Certified Wood

sustainability rating systems

Y

1 1 1 1

Possible Points: 110 Silver 50 to 59 points

Gold 60 to 79 points

Platinum 80 to 110

Fig 67

10 1

DRAFT 265


DRAFT 266

Fig 68

sustainability rating systems


Appendix A

Related Reports

The intent of this appendix is to give an overview of all reports related to landscape design and landscape construction for St. Elizabeths West Campus which have been referenced in the preparation of the Landscape Integration Plan. These reports can be found on the GSA’s document exchange website.


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix A:Related Report

I-26 6

Source

GSA Report/ Folder #

Title

Author

Date

GSA

1

St Elizabeths Model Community Complex

Bernard Hercenberg

1977

GSA

Wards of the nation: the macking of St. Elizabeths Hospital, 18521920

Frank Rives Millikan

1990

NPS Website

The Secretary of the Interior's Standards for the Treatment of Historic Properties and Guidelines for the Treatment of Cultural Landscapes

NPS

1992

GSA

1.2

Historic resources management plan

Devrouax and Purnell

1993

GSA

1.2

St Elizabeths hospital Archaeological Mgt Plan

Devrouax and Purnell

1993

NPS Website

NPS Preservation Brief 36

NPS, Birnbaum

1994

NPS Website

NPS 28: Cultural Resource Management Guideline

NPS

1998

Remarks

GSA

4

Phase I Environmental Site Assessment ECC Enviornmental 9-25-2000

Environmental Consultants and Contractors

2000

GSA

5

Phase II Environmental Assessment

Applied Environmental, Inc.

2002

GSA

7

Supplemental Phase II Env Assessment

Applied Environmental, Inc.

2002

GSA

6

ULI Advisory Service Panel Report

ULI

2002

GSA

16

ZAI Resource Tool

Zimmerman Associates

2004

In-depth history, burials, arch drawings, photos

GSA website

GSA PBS CAD Standards

GSA

2004

seed files and rules for CAD submittal

GSA

Ash Characterization Report

Applied Environmental, Inc.

2005

Boring locations, remediation suggestions, composition of fill many historic photos and present-day photos of buildings

GSA

12.1

Historic Preservation Report

John Milner Architects

2005

GSA

10.2

Land Use Feasability Study

Jones Lang LaSalle

2005

GSA

10.1

Landscape Assessment Plan

Heritage Landscapes and Robinson and Associates, Inc

2005

GSA

11

Phase I Arch Survey Bldg Landscape Arch Assess

Farewell Mills Gatsch Architects

2005

GSA

12

Preliminary Geotechnical Report

GeoConcepts Engineering

2005

GSA

75

Phase 1a Archeological Assessment

Farewell Mills Gatsch Architects

2005

GSA

20

Asbestos Tunnel Assessment A

Burgess and Niple

2006

GSA

20

Asbestos Tunnel Assessment B

Burgess and Niple

2006

a n d r o p o g o n a s s o c i at e s lt d .


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix A:Related Report

Source

GSA Report/ Folder #

Title

Author

Date

GSA

17

Draft Tunnel Inspection Report

Burgess and Niple

2006

GSA

35.3

Ground Penetrating Radar Study

Earth Resources Technology

2006

GSA

21

Preliminary Geotech Exploration

Burgess and Niple

2006

GSA

26

Road Condition Study

Burgess and Niple

2006

Security Briefing St Elizabeths West Campus

DHS

2006

GSA GSA

22

Substation Study

Burgess and Niple

2006

GSA

19

Tunnel Report

Burgess and Niple

2006

Bird Safe Building Guidelines

NYC Audubon Society

2007

NYC Audubon Society Website GSA

39

Enhanced Resource Conservation Final Report

Bartlett

2007

GSA

52

Final Preservation Planning St Elis W Cemetery

Chicora Foundation

2007

National Bald Eagle Management Guidelines

US Fish and Wildlife

2007

US Fish and Wildlife Website GSA

51

Ph 1 Archeological Survey

Greenhorne and O'Mara; Jones Lang laSalle

2007

GSA

51

Ph 2 NRHP Evaluation of 2 Archeological Sites

Greenhorne and O'Mara; Jones Lang laSalle

2007

GSA

50

Remedial Investigation Report

Greenhorne and O’Mara; Chesapeake Geosciences; Exponent, Ic.

2007

GSA

57

St E W Campus Utility Assessment

Delon Hampton and Associates

2007

GSA

49

St Es Campus Supp Program Dev Study A

OLBN Architectural Services

2007

Center Building Rehabilitation Study

Monument Construction Corporation

2007

GSA

GSA

63

Final Environmental Impact Statement

GSA

2008

GSA

66

Historic Preservation Guidelines

Oehrlein and Associates; Robinson and Associates

2008

Programmatic Agreement

GSA

2008

GSA GSA

65

Security Master Plan

Perkins and Will

2008

GSA

73

Emergency Hydrant. Water Supply Project

The Protection Engineering Group, PC

2008

Remarks

Tree data in Access database format, Full report document

no further recommendations for arch digs

Buildings

Comprehensive document

S e n s i t i v e B u t U n c l a ss i f i e d

I-267


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix A:Related Report

Source

GSA Report/ Folder #

Title

Author

Date

67

Final Master Plan

Jones Lang LaSalle

2008

GSA

61

Resource Conservation Database Update

Bartlett

2008

Addition to Bartlett survey- Tree and soil database, including GIS data

GSA

64

Transportation Management Program

Jones Lang LaSalle

2008

"A TMP is an employer’s active program to foster more efficient employee commuting patterns. The plan includes specific strategies to encourage change in employee travel mode, trip timing, frequency and length, and travel routes so as to reduce traffic congestion and improve air quality."

GSA

Double Security Fencing

Perkins and Will

2009

Andropogon

Soils Investigations for St. Elizabeths Campus

Craul Land Scientists/ Andropogon

2009

GSA

St. Elizabeths West Campus Landscape Preservation and Management Plan 75%

Heritage Landscapes

2009

Andropogon

St. Elizabeths Plateau Tree Inventory and Assessment of Selected Trees

Morris Arboretum/ Andropogon

2009

not yet posted, Arboricultural updates to Bartlett database of trees on the plateau likely to be disturbed during future construction

Andropogon

St. Elizabeths Cemetery Tree Inventory and Assessment Report

Morris Arboretum/ Andropogon

2009

not yet posted, Expansion upon Greenhorne and O'Mara's tree survey and tagging efforts around the cemetery; includes species, sizes and arboricultural recommendations

AA

Conceptual Design Narrative

Andropogon Associates

2009

Landscape design narrative for the USCG building

Cultural Landscape Report

Heritage Landscapes and Robinson and Associates, Inc

2009

Folder 38 not accessible/ missing data

Andropogon

Premliminary Hydrogeological Information

Geoconcepts

20092010

22 additional observation wells, 3 groundwater extraction wells, boring findings, comments

GSA

Civil War Cemetery Docs

Various

Various

Various surveys and history of the cemetery

Audubon of N. VA Website

Demonstration Sites: Native Landscapes in N. VA. (Preserved and Restored Habitats)

Audubon of N. VA

GSA

I-26 8

38, 77

a n d r o p o g o n a s s o c i at e s lt d .

Remarks

not yet posted, updated soil mapping and analysis

Good link to "successful" restorations of diff. types


Appendix B

Soil Investigations

by Tim Craul, Craul Land Scientists


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soil Investigations for Saint Elizabeth’s Campus July 6, 2009

B -270

a n d r o p o g o n a s s o c i at e s lt d .


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

Executive Summary Natural soil varies in its properties and characteristics across the landscape, but its composition, extent and performance is predictable by trained soil scientists. (Craul, 2000) The soils of urban and restoration sites has been altered to varying degrees by human activity and is unpredictable. Soil of both urban areas and restoration sites mostly has characteristics that limit or preclude plant growth, and are not plant‐root friendly (Craul and Craul, 2006). The proper and appropriate soil design is important for success on all landscape projects. In fact, it may even be more important for a successful and sustainable landscape project in small but very highly visible or valuable sites, where the appearance of failure would have a very serious detrimental aesthetic, economic, and professional impact. There is no one approach to planting soils that can be applied to any and all landscape architecture designs. A soil material must be found or a soil specifically designed for a given landscape architectural project that fits within the function of the site. The planting soil must perform both as a function of aesthetics (healthy plants) and as an operating ecosystem (sustainability). A combined holistic approach is required to planting soil design for the Department of Homeland Security Campus. The use of the site, site security, site prestige, construction schedule, and the bio‐physical aspects of the site must be the criteria used for site landscape design.

Conclusion The site investigation is the first step of the evaluation of in situ soils for the development of the campus in order to prioritize various landscapes for protection, remediation, renovation, and removal. Craul Land Scientist feel that to properly develop urban sites to make them sustainable, fit with the natural landscape, and meet LEEDS in the truest sense an understanding the soil/landscape and how to appropriately use/reuse the soils is of paramount concern. This report intends to cover these items to select protection areas, staging areas, locate problem soil/landscape areas with solutions to fix them, and to generally provide information to assist the Architects, Landscape Architects, and Contractors with planting soils in future construction. Respectfully Submitted,

Timothy A. Craul, CPSSc. SENSITIVE BUT UNCLASSIFIED

2

S e n s i t i v e B u t U n c l a ss i f i e d

B -271


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

Table of Contents Executive Summary .................................................................................................. 2 Conclusion................................................................................................................. 2 1.0 – General Site Conditions: ................................................................................. 4 1.1 – Weather .............................................................................................................................. 4 1.2– General Soil Conditions ........................................................................................................ 6 2.0 – Soils Descriptions:........................................................................................... 7 2.1 – Soil Evaluations ................................................................................................................... 9 2.2 – Site Analysis ...................................................................................................................... 10 3.0 – Site Specific Uses: ......................................................................................... 11 3.1 – Compacted Fill ................................................................................................................... 12 3.2 – Contaminated Fill .............................................................................................................. 13 3.3 – Mixed Natural Soils ........................................................................................................... 15 3.4 – Compacted Natural Soils ................................................................................................... 15 3.5 – Natural Soils ...................................................................................................................... 16 4.0 – Remediation Procedures ............................................................................... 16 4.1 – Tree soil reconditioning .................................................................................................... 16 4.2 – Organic Amendment ......................................................................................................... 19 4.3 – Soil Protection Matting ..................................................................................................... 19 4.4 – Tree Protection ................................................................................................................. 20 4.5 – General Lawn and Shrub Soil Remediation ....................................................................... 21 5.0 – Conclusions: .................................................................................................. 22 5.1 – Discussion .......................................................................................................................... 22 5.2 – Recommendations ............................................................................................................ 23 6.0 – Caveats ........................................................................................................... 24 Appendix .................................................................................................................. 26

SENSITIVE BUT UNCLASSIFIED

B -27 2

a n d r o p o g o n a s s o c i at e s lt d .

3


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

1.0 – General Site Conditions: I arrived at the site around 10:30AM. In attendance were Manishia Kaul, Laura Hansplant, and Emily McCoy of Andropogon Landscape Architects. We first met to go over the sections of the campus the required more detailed review and planned the investigation procedures.

1.1 – Weather

The site soils were generally moist under a clear sky with an average temperature around 84 degrees F. Temperatures for 2009 are well within normal trends. The rainfall for the spring and summer of 2009 is above normal averages. The data to the left and below is from the Weather Underground web site (http://www.wunderground.com/ NORMS/DisplayNORMS.asp?Airpor tCode=KDCA&StateCode=DC&Safe CityName=Washington&Units=non e&IATA=DCA&normals=on&record s=on)

SENSITIVE BUT UNCLASSIFIED

4

S e n s i t i v e B u t U n c l a ss i f i e d

B -27 3


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus Weather Data for 2009 at Reagan International Airport starting at January 1, 2009

SENSITIVE BUT UNCLASSIFIED

B -2 74

a n d r o p o g o n a s s o c i at e s lt d .

5


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

The majority of the east coast is within normal soil moisture ranges for this week. The soil moisture for the past year has been at normal or near normal conditions according to NOAA (http://lwf.ncdc.noaa.gov/oa/climate/research/prelim/drought/pdiimage.html)

1.2– General Soil Conditions

The soils of the site were moist due to a rain event on Saturday June 20, 2009 of 0.39 inch. The surface of the soils was generally dry without areas of standing water even within drainage swales or channelized drains. The soils of the site are wind‐blown silt loam and silty clay loam “loess” capping fluvialmarine, deltaic fans and alluvial terrace sediments. On the steeper portions of the site, the loess has eroded away and very gravelly sandy clay loam fluviomarine sediment remains. Soils with loess (grain sizes between 0.05 – 0.002 mm) as a parent material are typically subject to severe erosion by water and wind.

SENSITIVE BUT UNCLASSIFIED

6

S e n s i t i v e B u t U n c l a ss i f i e d

B -27 5


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

Soil series that have a fragipan such as the BELTSVILLE SERIES had free water observed directly above the fragipan. The depth to pan averaged about 24 inches, providing evidence of the moderately well drained nature of these soils. The CHRISTIANA SERIES does not have a fragipan within its standard profile but is typically mapped adjacent and at lower elevations to the BELTSVILLE SERIES so that subsurface water flowing across the BELTSVILLE fragipan will affect the internal drainage of the lower slopes.

2.0 – Soils Descriptions: The soil survey as generated by the National Cooperative Soil Survey has generally captured the different soil/landscapes within the site (Map 2.1). The Soil Survey could not delineate some the disturbed areas and fill zones that are smaller than the minimum delineations of soil mapping units for the scale of mapping for the District of Columbia survey report. The DC soil survey report was mapped at a scale of 1:12,000 which only allows soil/landscape delineations to be no smaller than 1.4 acres (Soil Survey Staff, Soil Survey Manual, Table 2.2). Also, the NCSS mapping would not separate variations in density, mixing, or age in soils with similar taxonomic classifications and properties. BELTSVILLE SERIES The Beltsville series consists of very deep, moderately well drained soils on uplands with moderately low and low saturated hydraulic conductivity within the fragipan. These soils formed in northern coastal plan silty eolian over loamy fluviomarine deposits. Slopes range from 0 to 40 percent. Mean annual temperature is 55 degrees F., and mean annual precipitation is 40 inches. TAXONOMIC CLASS: Fine‐loamy, mixed, semiactive, mesic Typic Fragiudults SENSITIVE BUT UNCLASSIFIED

B -276

a n d r o p o g o n a s s o c i at e s lt d .

7


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus CHILLUM SERIES The Chillum series consists of very deep, well drained soils on uplands with moderate saturated hydraulic conductivity in the subsoil with moderately slow to moderate in the underlying material. They formed in silty eolian material underlain by loamy marine sediments on dissected uplands of the coastal plain. Slopes range from 0 to 40 percent. Mean annual temperature is 55 degrees F., and mean annual precipitation is 42 inches. TAXONOMIC CLASS: Fine‐silty, mixed, semiactive, mesic Typic Hapludults CHRISTIANA SERIES The Christiana series consists of very deep, moderately well drained soils on uplands with moderately high to low saturated hydraulic conductivity. They formed in clayey fluviomarine deposits of summits, shoulders, and backslopes of interfluves. Slopes range from 0 to 40 percent.

Mean annual temperature is 52 ‐58 degrees F., and mean annual precipitation is 40 ‐ 47 inches. TAXONOMIC CLASS: Fine, kaolinitic, mesic Aquic Hapludults CROOM SERIES

The Croom series consists of very deep, well drained soils on uplands with moderately slow to moderate permeability. They formed in coastal plain fluvial and deltaic deposits of gravel, sand and clay. Slopes range from 0 to 40 percent. Mean annual temperature is 54 degrees F., and mean annual precipitation is 40 inches. TAXONOMIC CLASS: Loamy‐skeletal, mixed, semiactive, mesic Typic Hapludults MATAPEAKE SERIES The Matapeake series consists of very deep, well drained soils on uplands with moderate to moderately slow saturated hydraulic conductivity. They formed in coastal plain upland interfluves and side slopes capped by silty eolian sediments underlain by coarser fluvial or marine sediments.

Slopes range from 0 to 30 percent. Mean annual temperature is 56 degrees F., and mean annual precipitation is 40 inches. TAXONOMIC CLASS: Fine‐silty, mixed, semiactive, mesic Typic Hapludults MUIRKIRK SERIES

The Muirkirk series consists of very deep, well drained to somewhat excessively drained, moderately slow to slowly permeable soils on uplands. They formed in a coarse textured mantle and the underlying older clayey sediments. Slopes range from 0 to 40 percent. Mean annual temperature is 55 degrees F., and mean annual precipitation is 39 to 47 inches. TAXONOMIC CLASS: Clayey, kaolinitic, mesic Arenic Paleudults SASSAFRAS SERIES The Sassafras series consists of very deep, well drained soils on uplands with moderate to moderately slow permeability. They formed on coastal plain summits and side slopes derived from sandy marine and old alluvial sediments. Slopes range from 0 to 60 percent. Mean annual

temperature is 45 to 58 degrees F., and mean annual precipitation is 35 to 50 inches. TAXONOMIC CLASS: Fine‐loamy, siliceous, semiactive, mesic Typic Hapludults SENSITIVE BUT UNCLASSIFIED

8

S e n s i t i v e B u t U n c l a ss i f i e d

B -27 7


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus

2.1 – Soil Evaluations

Evaluation of the current soils on site have been mapped on a rectified orthophograph base of 2005 Maryland Coastal Areas with the Digital Elevation Model was downloaded from the USGS Seamless Data Distribution website (http://seamless.usgs.gov/website/seamless/index.htm) (See Map 2.2). The latest District of Columbia SSURGO soils data was (09/14/06) acquired from the USDA‐ NRCS Soil Data Mart (http://soildatamart.nrcs.usda.gov/) and the Web Soil Survey (http://websoilsurvey.nrcs.usda.gov/app/). The main plateau of the campus has either Matapeake or Beltsville series mapped. These soils are loess capped soils with extremely good properties for growing plants in their natural state. They are however very susceptible to erosion and compaction by any surface traffic. The Beltsville soil is moderately well drained with a dense fragipan that will limit its usefulness. Removal of the soil horizons above the pan will expose the dense soil, causing a wetter and more compact soil at the surface than currently on site. Subsurface water will also flow across the fragipan causing seeps and wet areas where the pan is exposed or where it approaches the surface. (Note the area around where the large white oak is barricaded by brickwork.) The Beltsville soil is not recommended for infiltration of stormwater BMP’s while the Matapeake would be acceptable in its natural state. Any typical urban mixing, compaction, or incorporation of anthropeic materials would decrease the soils natural usefulness for stormwater management. The steeper slopes are Christiana, Sassafras or Croom with a slope of between 18 and 60 percent. These areas are highly susceptible to erosion if disturbed. Construction on these slopes will have to be closely controlled and designed to divert runoff effectively to dissuade concentrated flow at any point. The Christiana soils are moderately well drained with “fragic” properties. In other words, Christiana soils are a degraded Beltsville soil and generally would not be acceptable for stormwater infiltration BMPs. SENSITIVE BUT UNCLASSIFIED

B -278

a n d r o p o g o n a s s o c i at e s lt d .

9


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix B: Soil Assessment Data & Reports

Soils Masterplan

Saint Elizabeth’s Campus Construction of the security fence and associated infrastructure must take the vulnerability of the natural soils to erosion into consideration. Any slope over 3 percent will erode on these loess soils. Note the criteria for HEL determinations from USDA‐FSA and NRCS for farmland as a basis.

2.2 – Site Analysis

The site was evaluated in four subsets; the south complexes that include the open oval bounded by Redwood Drive and Spruce Street and the buildings along Persimmon Street. The second area was the “Point” on Golden Raintree Drive and the large lawn in front of the main building. The third area was the Civil War Cemetery and associated steep slopes. The last area was incinerator fill area and steep slopes just south and east of Willow and Persimmon Streets (See Soils Map 2.2) Craul Land Scientists have generated specific tables for the currently mapped soils within the site using USDA‐NRCS generated reports from the Soil Data Mart. This data pertains only to soils mapped by the National Cooperative Soil Survey using their standards and limitations. The interpretations that were produced are: Table Name (Located in Appendix) Contribution to Landscape Master Plan Agricultural Disposal of Wastewater by Provides insight into stormwater management using Rapid infiltration and Slow Rate infiltration BMP Treatment Dwellings and Small Commercial Provides information on subsurface soil properties that Buildings would affect landscape infrastructure Chemical Soil Properties Provides information on soil chemical properties for plant growth Engineering Soil Properties Provides Engineering Properties for landscape infrastructure. Physical Soil Properties Provides soil physical properties used in all major interpretations. RUSLE2 Attributes Lists soil properties for direct input into the Revised Universal Soil Loss Equation Sewage Disposal Additional interpretations for assisting in Stormwater Management BMP development and placement Water Features Soil properties that will effect landscape underdrainage and stormwater management. Using the above tables, the following maps were generated to provide interpretations for Tree and Shrub growth, Soil Reaction, and Stormwater Management based on historic urban soil modification noted during our field investigation. SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus Map Surface Soil Reaction Increase over Normal Ranges

Description Map showing predicted increase over natural soil pH due to urban influences Soil Reaction using Local Modification Additive map showing areas of modified soil reaction due Overlay to human influences. The bluer the color of the delineation, the more alkaline the soil surface will tend to be. Site Condition Modification of Map indicating human affected soil limitations that would Suitability for Stormwater Infiltration modify normal interpretations for Stormwater Management BMPs. Soil Suitability for Stormwater Map showing accumulated detrimental soil properties for Management BMPs successful stormwater management practice. The redder the color, the greater the limitations for standard stormwater BMP implementation. Woodland Growth Suitability General overlay map showing accumulated risk of tree and shrub mortality of new plantings without soil modification. The redder the color, the more intense the remediation of the soils will be required to sustain woody plants.

3.0 – Site Specific Uses: There are still pristine areas of natural soils within the campus that must be protected due to their ability to support the plants currently growing upon them. The majority of trees are mature, irreplaceable and historically significant to the site. They require that the soils they are currently growing in maintain their natural properties. Access to these areas must be severely restricted during the construction phase. Some areas of the campus have been disturbed and will require remediation based on the level of damage to their agronomic tilth such as physical, chemical, and biologic properties. These areas can be used as staging or areas that can accept underground utilities if the final soil is amended, imported, or renovated to achieve an acceptable plant growth media. The area to the south east where a new building is to be constructed has its footprint within a filled swale. The swale should be left SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus intact because of the water that is flowing on the surface and subsurface through this area.

The fence line along the steep slopes should take into consideration the soil and the affects of construction, infrastructure, and patrol path on the erodibility of the slope. Construction should not run up and down the slope vertically, nor should it be placed on unstable slopes. The fencing and associated infrastructure should be run across steeper slopes on the contour and on areas that do not have historic tree vegetation. This area will require extensive grading to redirect surface water flow away from the slopes and fencing. It is suggested that the grading plan for the building proposed at the head of the south drainage have slopes that redirect surface stormwater runoff away from the steep slopes designated with slips and eroded spots on the general soil mapping.

3.1 – Compacted Fill

The areas noted as compacted fill materials are a mix of gravels and sandy clay loam fine earth fractions. Gravelly sandy loam fill material compacted up to 275 lbs./in2 in the surface 4 inches and over 350 lbs./in2 below 4 inches.

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These areas will be excellent for staging for construction since the soils have already been degraded to the point of not being able to support large plantings due to their compaction. We suggest that these areas be used for staging during construction and either renovate or replace the planting soil post‐ construction. The decision to renovate or to replace should be made during construction based on the damage to the soils.

3.2 – Contaminated Fill

The drainage swale areas below the power plant and incinerator located below Birch Street have been filled with incinerator ash and clinkers made up of melted Pyrex glass, plastics, and other incomplete burnables. The Pyrex is most likely the cause of the Dioxins as well as some lead within the water table. There is a gravelly sandy loam cap fill that also contains concrete, asphalt, and other hard fill material that was used to bury the incinerator waste. It is quite permeable and subject to erosion due to its permeable nature. There was observable water scours located in the central portion of the fill. SENSITIVE BUT UNCLASSIFIED

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The photo to the left shows a tree fall with its roots encrusted with semi‐melted glass and other debris. This tree fell over because of the limited rooting volume and structural support of the incinerator waste. The tree was also within the slough which also may have led to the undercutting of the root system. The incinerator waste needs to be capped and shaped more effectively to allow runoff not to scour into the waste itself. The incinerator waste fill and other upland grading is also redirecting runoff into the steep slope at the beach grove. The steep slope below the current fence is showing signs of instability. The trees near the base of slope are bent and not growing straight.

This instability of the slope is an indicator of a larger problem with the security fence. Over time the fence area could be undercut and might not be stable. Adding a security path for personnel to patrol the fence area will increase impermeable surfaces causing greater runoff and possibility accelerating the slope erosion. In addition, the current slope is of a natural soil with the ability to support large trees of historic value to the site. By moving the construction to the high portions of the down‐slope slough and SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus regrading that area to accept the fence and associated infrastructure will save the slope and the vegetation.

The scour can be seen within this photo that follows along the storm sewer. Notice that the manhole access is quite a bit above the surrounding landscape surface. This might be due to years of erosion.

3.3 – Mixed Natural Soils

Where underground utilities have been recently installed or repaired, the natural soil has been mixed causing the soil profile to be un‐recognizable. The soils within these areas are compacted, have lower levels of soil organic matter (SOM) than their natural state. Compaction rates typically exceeds 300 lbs./in2 below 4 inches of the surface. These areas will require renovation such as deep loosening, and a high rate of compost incorporation to reconstruct viable topsoil. Turf grasses will grow, but at a reduced rate. These areas also can harbor dense layers that can perch water causing wet areas within the lawn that affects trees, turf and shrubs. Wetness and soil compaction usually increases the mortality rate of the plants.

3.4 – Compacted Natural Soils

Local natural soils are typically old fill or have been compacted to higher densities than normal but less than other places due to their age. These soils were mixed or compacted some time ago so that the natural soil formation processes reverted the material back to a soil that has identifiable diagnostic horizons. Some of the natural profile is still recognizable. Generally, these areas will only require some compaction remediation, organic amendment and reseeding. These areas are in front of the main building complex, around the main gate, the main dining hall across from the GSA office, and between all of the buildings. These areas can be renovated by SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus incorporating additional organic matter in the form of compost. The incorporation will also loosen the compacted surface 6 inches allowing a deeper rooting volume for the turf. Tree areas may need individual applications such as air spading, radial trenching or vertical mulching on a case by case basis.

3.5 – Natural Soils

The natural soils are located along the overlook point, within the main oval just southeast of the GSA office bounded by Spruce Street and Redwood Drive, and around the cemetery. With some exceptions for minor excavations for utilities, these soils are pristine and need to be protected. This is one area that needs protection from erosion due to desire lines to the civil war cemetery. This slope will continue to erode until the pathway is stabilized. Other areas that will get this type of use will also erode such as the security fence, causing instability of the slopes and any infrastructure adjacent to them. Since the subsoil is exposed and the SOM has been washed away, re‐vegetation of the area is problematic until the SOM and compaction is addressed.

4.0 – Remediation Procedures The following recommendations for protection, remediation, and renovation of the soils within the campus are specified based on previous encounters with institutional planting soil problems. These procedures are being implemented at Princeton University, The Ohio State University, Harvard University, and other locations.

4.1 – Tree soil reconditioning

A. Soil Conditions Requiring Remediation: These conditions are noted from slight to severe. Compaction is restrictive for tree roots at a penetration resistance of greater than 250 lbs/in 2.

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Saint Elizabeth’s Campus Primary Condition Soil compaction of 6-12” depth Soil compaction of 6-12” depth Soil compaction of >12’” depth Soil compaction of >12’” depth

Secondary Condition None

Remediation Air spading of the area under the tree crown.

Raised roots Raised Intertwined Roots within a Copse of Trees Raised roots Individual Tree

Air spading of the area under the tree crown. Additional soils placed on raised roots. Vertical mulching Additional soils placed on raised roots. Radial Trenching Additional soils placed on raised roots.

B. REMEDIATION PROCEDURES

1. Air Spading: First delineate the major framework roots. When roots are located, push the air into the ground to a depth of 12 inches. Ensure that the soil moisture is between 5‐15 percent. 2. Raised Root Soil Fill: Raised root systems above the soil surface shall be covered with soil to provide root plate weight and more accessible rooting volume. After the existing soil has been de‐compacted, the filling soil shall be placed in no more than 3 inches thick per year. The soil used shall be a 1:1 mix of existing site soil and S1 material. Ensure that the soil moisture is between 5 to 15 percent before any soil remediation is performed, 3. Vertical Mulching: Vertical Mulching shall be used in situations when there are several trees with overlapping roots that are difficult to identify and locate. Core the soil to a depth of 12‐ 18 inches using 6 inch diameter auger in a grid pattern with holes approximately 3 feet apart on center. Take care to not excessively damage many large framework roots. The area to be cored shall be the entire area, excluding 3 to 5 foot radius away from the tree trunk to the limits of the tree crown’s drip edge. Scratch the walls of the core hole before filling the hole with a soil using a 2:1 mix with existing soil from the hole and the recommended compost material. Ensure that the soil moisture is between 5 to 15 percent before any soil remediation is performed,

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4. Radial Trenching: Radial trenching shall be used when the soil compaction is severe in and around single trees or when structural framework roots ore easily identified and located. First delineate the major framework roots. Ensure that the soil moisture is between 5‐15 percent prior to accomplishing any soil work. Starting 3 to 5 feet from the trunk, dig a trench between the framework roots using a 12 inch wide bucket down to a depth of 12 to 18 inches out to just beyond the drip edge of the tree crown. Scarify the edges of the trench to remove any soil smearing. Fill the trench with soil using a 1:1 mix with existing soil from the excavation and the recommended compost material. See detail below.

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4.2 – Organic Amendment Criteria

Type

Carbon/Nitrogen Ratio

Degree of Maturity

Foreign Material Organic Matter % Reaction Ammonium Salinity

Test Method

Dewer Self Heating or Solvita Maturity Index or CO2 Evolution Dry wt. Dry wt. 1:1 water extract 1:1 paste

Nutrient Content

extract

Heavy Metals

extract

Acceptable Range Brewer’s waste, composted sewage sludge without excessive content of woodchips or leaf mulches are also acceptable. Composted municipal waste (chipped, shredded and screened wood, leaves, bark, etc.) alone is not acceptable unless it meets all of the criteria noted 11:1 – 22:1 VI – V 6 – 8 1.2 % C/day < 1” dia. And < 2% (of total) 25 – 55% 5.5 – 8.0 < 200 ppm < 1.5 mS/cm Contains some nitrogen, phosphorus, potassium, calcium, magnesium, sodium and micronutrients including iron, copper, boron, and manganese. Nutrients shall be present in appropriate agricultural and horticultural proportions to prevent ion antagonism. Concentrations of zinc, mercury, cadmium, lead, nickel, chromium, and copper must be below EPA standards for biosolid applications to soils with human activity.

NOTE: Penn State’s Agricultural Analytical Services Laboratory Compost Test 3A fulfills this requirement and meets strict US Compost Council standards.

4.3 – Soil Protection Matting

Some construction sites often must traverse existing landscapes. In an effort to limit the effects of compaction to the existing soils, matting can be applied for various levels of traffic intensity. Low intensity such as foot traffic will not require as significant construction as heavy equipment. Mulch Mat: Use 6 to 8 inches of mulch over geotextile to reduce light traffic such as pedestrian and light cart traffic. SENSITIVE BUT UNCLASSIFIED

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Surface Mat: Cover the above mulch mat with rubber matting or plywood for light vehicle traffic such as high lifts, cherry pickers, 1 ton trucks with one or two passes. Gravel Mat: Use 2B crushed stone over geotextile for heavier traffic like dump trucks, cranes, and front end loaders.

Procedures for removal of the protective mats should follow these basic steps to ensure that the soil health to returned to a level supportive of vegetative growth. Remove the matting material carefully to restrict any traffic outside of the boundaries of the protected area.

4.4 – Tree Protection

Tree protection must be barricaded a radius distance of 1.5 times the height of the tree from their trunks. All efforts must be made to protect as much of the area under large trees as possible and where several trees are close, the entire area must be protected.

Tree Protection

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4.5 – General Lawn and Shrub Soil Remediation

The following procedures are generally for turf applications, but can be used for small shrubs and flower beds as well. It is imperative that soil moisture is accounted for during remediation of the natural soils on site because of their fragility and tendency to compact to levels that totally inhibit plant root elongation, aeration, and water infiltration.

Primary Condition Soil compaction of 4-12” depth

Secondary Condition None

Remediation Mechanical soil loosening to a depth of approximately 8 inches

1. Only start tillage operations when the soil moisture is around 10% by weight, or when tillage equipment does not leave large clods or smearing of soil faces. Typically, this is after 2 days of good drying weather following a rain event and before the soil becomes too dry to raise dust. 2. Equipment operations shall be conducted exactly as if a farmer is readying a field for planting. Excessive equipment trips over the lawn area are to be severely restricted. No other access for anyone of other than the landscape contractor shall be allowed after tillage has started and the area has been planted. 3. Till the lawn area with agricultural equipment such as a chisel plow to a depth of 6 to 8 inches. 4. Run a rock rake or rock‐hound over the area to remove coarse fragments down to 2 inches in diameter. 5. Apply 1 inch of approved compost on the surface and incorporate with a gang disk or large roto‐tiller. Ensure that only one pass per area is completed. The rate for this application is 3.1 CY/1000 ft2. 6. For areas designated as “fill” or “mixed” soil in Map 2.2, re‐apply another 1 inch layer of approved compost to the surface and incorporate with a gang disk or roto‐tiller perpendicular to the first pass. Again, ensure that only one pass per area is completed. (the overall rate of compost is 6.3 CY/1000 ft2) 7. Equipment turn areas at end of passes or other areas may need additional loosening if penetration resistance of the surface 6 inches is greater than 175 lbs/in2. 8. Final grade the area. DO NOT use a renovator to grade the lawn because of the resulting damage to soil structure. Fine rakes, chain rakes or spring tooth harrows is acceptable. The Soil Scientist can assist the Landscape Contractor in acceptable means to limit compaction and provide a smooth planting bed for the meadow areas. SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus 9. Seed the area with approved lawn or meadow plant mix. Restrict all traffic over the area until vegetation has completely established. Typically, this shall be within one growing season.

5.0 – Conclusions: The campus soil is generally in relatively reasonable shape with areas of pristine natural soils around the older buildings and in scattered tree lawns. Newer buildings with their underground utilities have scarred the soils by mixing the natural soils so that the topsoil is no longer at the surface. The lower non‐productive subsoil currently at the surface is showing low plant productivity and lawns with a greater propensity for weeds. Other areas outside what has been mapped that has some urban disturbance can be renovated with soil amendments to boost SOM, mechanical loosening to reduce soil compaction, and proper protections against future damage,

5.1 – Discussion

The soils currently on the site are modifications of the natural soils that have mapped as part of the Soil Survey of the District of Columbia (See USDA‐NRCS Web Soil Survey Map in Appendix, Map 1). The soils investigation of the site described urban variations that are not commonly conveyed in NCSS soil mapping such as differences in compaction and mixing of the natural soil profile. Areas of contaminated fill are present in the drainage sloughs of the southern portion of the site. The capping fill material is too erosive to permanently cover the contaminated fill. Additional soil material is needed to stabilize the sloughs and prevent significant erosion of the contaminated fill. The sloughs need to be regraded to protect steeper slopes that harbor historic beach tree groves and to better fit security measures to the landscape for protection and sustainability. Other areas of fill on site have been compacted to levels that cannot support trees or shrubs. These areas will require significant renovation. It is our recommendation that these highly disturbed areas be used as staging for construction, leaving the undisturbed areas free of traffic (See Map 2.2 in Appendix).

5.1.1 Soil Reaction Variations: The soils impacted by urban environments with the dissolution of concrete and mortar over time tend to raise the overall soil pH. The soil pH will try to reach equilibrium between the natural soil and the concrete. Standard concrete has a pH of around 8.3 and the soils of this area are naturally between 5.5 and 6.7. The map “Soil Reaction using Local Modification Overlay” provided in the Appendix shows the estimated soil pH increase over the natural background pH of the mapped soils. The bluer the color of the delineation indicates a higher surface soil reaction. Field pH readings of grab samples generally reflect observed tends (at the site and elsewhere in temperate urban environments. SENSITIVE BUT UNCLASSIFIED

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5.1.2 Stormwater BMP Restrictions The map “Site Condition Modification of Suitability for Stormwater Infiltration“ was generated using increases in overall bulk density observed during the site investigation using cone penetrometer readings and soil profile observations. The measurements were calibrated with readings of the natural soils found and past experience in urban soil compaction ranges. The map is a generalization of soil factors that would affect stormwater infiltration. Such factors are soil permeability (gases, water, roots, and organisms), soil content of coarse fragments and depletion of soil organic matter commonly found in urban environments. The map “Soil Suitability for Stormwater Management BMPs” is an overlay of the major natural limitation to stormwater infiltration structures (internal drainage class) of the soils mapped by the USDA‐NRCS with the modifications to that property with the current site soil property limitations to runoff limitations. The redder the color of the delineation, the greater the limitation is for stormwater infiltration.

5.1.3 Tree Growth Limitations: Tree and large shrub growth is based on these basic properties developed by K Coder, July 2000 at The University of Georgia. The soil map spatial data generated by Craul Land Scientists includes a field where these properties are generalized to produce a numeric range of limitations based on affected soil properties observed. The soil property ranges that Dr Coder considers for adequate tree growth is listed in the following table: Requirements Root Resource Minimal Maxium Soil Oxygen 3% 21% Pore Space (air) 12% 60% ‐ 1.4 g/cc clay (non‐cohesive) Soil Bulk Density ‐ 1.5 silt g/cc ‐ 1.8 sand g/cc 435 lbs/in2 Penetration Resistance 0.01 lbs/in2 (moisture dependent) Temperature Limits 40o F 94o F Soil Reaction 3.5 8.2 “Woodland Growth Suitability” map shows locations within the site where current soils have limitations to sustain new tree plantings and current trees are showing signs of stress due to soil conditions. The redder the color of the delineations dictates the severity of the limitations for tree and large shrub growth. Renovation to these areas should be based on the extensiveness of the compaction, pH, mixing, lack of soil organic matter, and degraded soil structure. The greater the severity of the problems determines the extent of the renovation. Review Part 4.1 for observable conditions and measurements that direct the type and course of remediation of the soils.

5.2 – Recommendations

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Saint Elizabeth’s Campus The following recommendations are made to properly develop the campus and still maintain the aesthetic appearance of the landscape. To achieve this goal, the soil/landscape must be fully considered in form and function. 1. The pristine areas of natural soil with large historic trees should be rigorously protected. Craul Land Scientists strongly recommend that the areas marked in green on the soil investigation map be barricaded during construction to limit the wandering nature of construction staging. For large historic trees scheduled to be saved should also be barricaded a radius distance of 1.5 times the height of the tree from their trunks. The absolute minimum distance should be 1 tree height radius around the protected tree. An effort must be made to protect as much of the area under large trees as possible. 2. Traffic lanes across protected soils must be limited to areas where sidewalks or roads are to be placed. Within other areas, a matting system should be used to protect the soil from compaction and damage to the inherent soil structure. 3. Steep slopes should not be developed to reduce erosion during and post‐construction. Where absolutely required for security purposes, the fencing and associated infrastructure to be made to fit the landscape and be designed not to accelerate soil erosion or degrade existing historic tree groves. We suggest that moving the fence in certain places to the reshaped fill material will effectively reduce the areas of steep slopes affected. The fencing should follow the contour of the slope as much as possible. 4. Remediation of existing soils should be based on the extent of the damage. Complete fill soils should be replaced with imported soils to cap the fill. Areas with full mixing of the profile will require a deep loosening down to 12‐18 inches and addition of fully cured compost at a rate of around 6.3 CY/1000 ft2 or two applications of 1 inch of compost incorporated to a depth of 4 to 6 inches. The slightly compacted natural soils can be amended with 3.1 CY/1000 ft2 or 1 inch of compost incorporated to 4 to 6 inches. The compost incorporation will loosen the soil enough for turf grasses. Trees and shrubs may need additional remediation on a case by case basis. 5. For new construction, the planting soils directly around the new buildings should be a sand based system to allow for several crucial functions. A sand based system resists compaction typically caused during placement, allowing for good permeability even when compacted. Soil permeability by definition is the ability of a soil to allow penetration of water, nutrients, roots and gases throughout its profile. The sand based planting soil will also allow for ease in installation, and has a higher workable soil moisture so that it can be installed soon after heavy rain events leading to less delays in the construction schedule.

6.0 – Caveats The procedures and suggestions of corrective measures noted within this document cannot be assured unless Craul Land Scientists are involved in the design and construction administration. SENSITIVE BUT UNCLASSIFIED

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Saint Elizabeth’s Campus Dealing with natural processes always has elements of uncertainty. Craul Land Scientists looks at the whole processes involved in a landscape project, from soils to hydrology, species selection and biologic processes, to sunlight, heat loads and evapotranspiration that we call “Biophysical Analysis”. We attempt to figure out all these aspects to best of current technology and knowledge, but nature still has aspects that are not fully understood.

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Appendix

Please see the attached CD for the detailed appendix provided by Craul Land Scientist.

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Appendix C

St. Elizabeths Tree Database - Bartlett Tags Please see the attached CD for the Microsoft Excel, AutoCAD and ArcGIS database files for the information regarding the campus trees originally tagged and located by Bartlett Tree Experts (refer to GSA’s Buzzsaw Exchange web site for the original database created by Bartlett). This current database consists of Bartlett’s original data, in addition to updated and additional data provided by Morris Arboretum and Andropogon Associates. (Please note that the locations/coordinates of these trees were originally recorded by Bartlett Tree Experts using GPS, not field survey. Therefore, the actual field locations may differ from the mapped graphic, Andropogon Associates does not guarantee these locations.)


S t . E l i z a b e t h s We s t C a m p u s – L a n d s c a p e I nt e g r a t i o n P l a n Appendix C: St. Elizabeths Tree Database - Bartlett Tags

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Appendix D

St. Elizabeths Tree Database – Greenhorne & O’Mara Tags

Please see the attached DVD for the Microsoft Excel, AutoCAD and ArcGIS database files for the information regarding the campus trees tagged by Greenhorne and O’Mara. This information/ database consists of Greenhorne and O’Mara’s survey points and tag numbers, in addition to updated and additional data provided by Morris Arboretum and Andropogon Associates. (Please note that the locations/coordinates of these trees were originally recorded by Greenhorne and O’Mara using GPS, not field survey. Therefore, the actual field locations may differ from the mapped graphic, Andropogon Associates does not guarantee these locations.)


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x D : St . E l i z a b e t h s Tr e e D at a b a s e - G r e e n h o r n e & O ’M a r a Ta g s

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Appendix E

Tree Data Procedure Logs

Please see the attached DVD for the file types mentioned in this appendix. Tree Data Procedure Logs consists of a summarized explanation of the consolidation of all known tree data for St. Elizabeths West Campus and the procedures logs for how that data was processed. (Please note that the locations/coordinates of these trees were originally recorded by Greenhorne and O’Mara using GPS, not field survey. Therefore, the actual field locations may differ from the mapped graphic, Andropogon Associates does not guarantee these locations.)


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x E : Tr e e Dat a P r o c e d u r e L og s

File Name

Appox. Spatial Location of Data

File types

Data Included

Data Source(s)

Original Units

Original Coordinate System

GO_2009_trees_points

West and north landscape, MA data for trees in and around

dwg, shp (points)

GO provided spatial survey of 1607 trees on west and north part of campus, Morris Arboretum identified and characterized 343 trees in and around cemetery, GO tags different number sequence than Bartlett

Greenhorne and O’Mara; Morris Arboretum

meters

MD. State Plane NAD83

Plateau

dwg, shp (points)

Bartlett data (with Heritage age data) updated by Morris Arboretum and Andropogon, Bartlett tags different number sequence than GO tags, Heritage data merged based on Bartlett tag numbers

Bartlett, Andropogon, Morris Arboretum, Heritage Landscapes

feet

MD. State Plane NAD83

Plateau

dwg, shp

Bartlett data (with Heritage age data) updated by Morris Arboretum and Andropogon, Bartlett tags different number sequence than GO tags, Heritage data merged based on Bartlett tag numbers

Bartlett, Andropogon, Morris Arboretum, Heritage Landscapes

feet

MD. State Plane NAD83

Cemetery

dwg, shp (points)

GO provided spatial survey of 1607 trees on west and north part of campus, Morris Arboretum identified and characterized 343 trees in and around cemetery, GO tags different number sequence than Bartlett

Greenhorne and O’Mara; Morris Arboretum

meters

MD. State Plane NAD83

HL_2009_trees

Entire campus

dwg, shp

Heritage CAD polygons georeferenced by WHGA, 527 of 1167 tree polygons have embedded data (HL plant codes)

Heritage Landscapes

meters (WHGA), inches (HL)

MD. State Plane NAD83 (WHGA), unknown (HL)

HL_2009_trees_alldata

Entire campus

dwg, shp

HL_2009_trees data merged with Heritage’s tree spreadsheet

Heritage Landscapes

meters (WHGA), inches (HL)

MD. State Plane NAD83 (WHGA), unknown (HL)

HL_2009_trees_ Aadelete

Entire campus

dwg, shp

HL_2009_trees data merged with Heritage’s tree spreadsheet, trees overlapping with Bartlett and/ or those with a Bartlett tag number were deleted

Heritage Landscapes

meters (WHGA), inches (HL)

MD. State Plane NAD83 (WHGA), unknown (HL)

TRZ_01_20091203 (tree protection zones)

Plateau

dwg, shp (points)

Bartlett data (with Heritage age data) updated by Morris Arboretum and Andropogon, Bartlett tags different number sequence than GO tags

Bartlett, Andropogon, Morris Arboretum, Heritage Landscapes

feet

MD. State Plane NAD83

SRZ_01_20091203 (structural root zone calculations)

Plateau

dwg, shp (points)

Bartlett data (with Heritage age data) updated by Morris Arboretum and Andropogon, Bartlett tags different number sequence than GO tags

Bartlett, Andropogon, Morris Arboretum, Heritage Landscapes

feet

MD. State Plane NAD83

SENSITIVE BUT UNCLASSIFIED

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File Name

Original File Name

Brief Procedure Log

Notes

GO_2009_trees_points

Trees.dwg (field work 5-28-2009)

x, y coordinates used to make point data in GIS, attribute data joined based on tag number> exported to .shp and CAD

St Elizabeths Tree Aug 08.mbd

x, y coordinates used to make point data in GIS> attribute data joined based on tag number> merged with HL spreadsheet data where applicable> exported to .shp and CAD

any trees that were removed or dead since BT surveyed in Aug 2008 were removed from dbase

St Elizabeths Tree Aug 08.mbd

x, y coordinates used to make point data in GIS> attribute data joined based on tag number> merged with HL spreadsheet data where applicable> exported to .shp and CAD

any trees that were removed or dead since BT surveyed in Aug 2008 were removed from dbase

Trees.dwg (field work 5-28-2009)

x, y coordinates used to make point data in GIS, attribute data joined based on tag number>canopy’s expressed using the buffer tool> exported to .shp and CAD

HL_2009_trees

Latest Heritage.dwg (WHGA), STE_EC-2009 (HL)

WHGA georeferenced and scaled to meters from inches Heritage’s tree data in CAD> CAD brought into GIS> exported to shp and CAD

HL_2009_trees_alldata

Latest Heritage.dwg (WHGA), STE_EC-2009 (HL) STE-HeritagePlantList2009_20091105.xls

HL_2009_trees. Shp> merged data with PlantList2009_20091105. xls based on HL tree code> exported to shp and CAD

HL_2009_trees_ Aadelete

Latest Heritage.dwg (WHGA), STE_EC-2009 (HL) STE-HeritagePlantList2009_20091105.xls

HL_2009_trees_alldata. Shp> shapes with Bartlett tags deleted> shapes overlapping/ appear to be represented in the Bartlett database were deleted

shapes that were overlapping/ appear to be represented in the Bartlett database were deleted in order to ensure the same tree was not represented more than once

TRZ_01_20091203 (tree protection zones)

St Elizabeths Tree Aug 08.mbd

x, y coordinates used to make point data in GIS> attribute data joined based on tag number> merged with GO tree point data where applicable> exported to .shp and CAD

any trees that were removed or dead since BT surveyed in Aug 2008 were removed from dbase, TPZ provided my Andropogon using Matheny and Clark’s calculation for TPZ’s

SRZ_01_20091203 (structural root zone calculations)

St Elizabeths Tree Aug 08.mbd

x, y coordinates used to make point data in GIS> attribute data joined based on tag number> merged with GO tree point data where applicable> exported to .shp and CAD

any trees that were removed or dead since BT surveyed in Aug 2008 were removed from dbase, SRZ’s provided by Morris

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

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Appendix F

Individual Tree Assessment Methodology

The following methodology, designed by Andropogon Associates, provides a means of comparing the relative value of individual trees. Ideally, the goal during construction is to minimize risk to all trees. However, when evaluating options for construction methodology and sequencing, it is helpful to have a guide for trees that require the highest protection levels, and ones that may be appropriately exposed to a higher level of risk.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x F : I n d i v i d ua l Tr e e A s s e s s m e nt Me t h o d o l og y

Vegetation Assessment Methodology - Individual Trees Individual trees are rated using a Tree Value Index based on a collective evaluation of four factors: cultural significance, age, condition (health) and rarity (unusualness). Each of these factors is scored individually between 0 and 1, for a combined Index score of up to 4. In addition, there are four Overlay Factors which are shown separately for consideration, including: trees original to the historic, 1937 campus (positive factor); aggressive invasiveness (red flag); epidemic disease concerns (red flag); poor health (red flag); and species related health/safety concerns (red flag). 1. Overlay Factors (shown as individual symbols) a. Positive Factors (Gold Stars): i. Trees original to the historic 1937 campus b. Negative Factors (Red Flags): i. Aggressively to Moderately Invasive [note this category does not include naturalized species that are not pests] ii. Emerging epidemic disease of species-wide concern iii. Health, safety and welfare [typically weak wood, to be added to data set] iv. Poor Condition [unlikely to successfully recover despite intervention ] [Sources: Jason Lubar, Morris Arboretum; Bartlett Tree Report]

2. Tree Value Index considers the following four factors: a. Cultural Significance i. Rating 1. 0.00 = no cultural significance 2. 1.00 = CLR, SIS, NR/ NHL ii. Sources: 1. Cultural Landscape Report. (O’Donnell, Patricia M., Heritage Landscapes LLC and Robinson Judith, et al, Robinson & Associates, 2009) 2. Final Master Plan (JLL) a. Contributing, character-defining and contributing resources as defined by the Cultural Landscape Report (CLR) by Heritage Landscapes b. National register (NR)/ national historic landmark (NHL) and Secretary of Interior’s Standards for the Treatment of Cultural Landscapes (SIS)

SENSITIVE BUT UNCLASSIFIED

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x F : I n d i v i d ua l Tr e e A s s e s s m e nt Me t h o d o l og y

b. Age i. Rating 1. 1960 – present = 0 [~50 years] 2. 1937 – 1960 = 0.50 [~50-71 years] 3. 1937+ = 1 [>71 years] ii. Sources: 1. Bartlett - tree’s diameter 2. Jason Lubar (Certified Arborist, Morris Arboretum’s Urban Forestry Consultants)Tree Age Estimation Report 3. Heritage Landscapes- CLR, time periods of significance c. Condition i. Rating 1. Poor = 0.00 [Bartlett ‘poor’ = multiple significant problems and unlikely to recover despite intervention – see also Overlay Factors below] 2. Excellent to Fair = 1 ii. Sources 1. Bartlett (condition class) 2. Andropogon field work [noted recent deaths/ severe damage, ie lightening] d. Rarity (Unusualness) i. Rating 1. 0.00 = abundant – normal (scored 5-3 per Morris Arboretum) 2. 0.50 = unusual (scored 2 per Morris Arboretum) 3. 1.00 = rare (scored 1 per Morris Arboretum) ii. Sources 1. Morris Arboretum’s Urban Forestry Consultants (Jason Lubar) - Mature Size and Rarity Report a. 5 = expected numerous in this local area b. 4 = expected abundant in this area c. 3 = normal for this area d. 2 = unusual tree species SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

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e. 1 = very unusual tree species

3. Tree Value Index Calculations a. Combined calculation includes: Age Index + Rarity Index + Character Defining Feature+ Condition= Combined Importance [Value] b. Calculation Range [combined score 0 to 4 max possible points] i. 0 = Low ii. 0 – 1.00 = Fair iii. 1.01 – 2.00 = Good iv. 2.01 – 3.00 = Great v. 3.01 – 4.00 = Best

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Appendix G

Existing Native Plant Community Summary

The identification of existing plant communities on St. Elizabeths West Campus was based on several site observations and descriptions of plant communities from NatureServe. NatureServe is a non-profit organization that is an umbrella organization that has compiled vegetation data, such as plant community data, from several state natural heritage member programs within a webbased information resource called NatureServe Explorer. These communities are also defined by the International Classification of Ecological Communities: Terrestrial Vegetation of the United States (Grossman et al. 1998) and the Ecological Systems of the United States: A Working Classification of U.S. Terrestrial Systems (Comer et al. 2003). The descriptions provided by NatureServe were used to match forest stands on the campus with these classified communities based on the raw data collected from 3 site visits. The methodology for pairing NatureServe data with specific site observations was adopted from NatureServe’s methodology for Classification of Standard Ecological Units.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix G: Existing Native Plant Community Summary

Plant Community Name

Association

Alliance

Dominant and characteristic species

Other species

American Beech Chestnut Oak Forest

Northeastern Coastal Plain/ Piedmont OakBeech/ Heath Forest

Fagus grandifolia- Quercus rubra- Quercus alba

• • • • • •

(upland slope, dry) (Fagus grandifolia - Quercus (alba, velutina, prinus)/ Kalmia latifolia)

Fagus randifolia Quercus prinus Quercus alba Quercus velutina Kalmia latifolia Cornus florida

• • • • •

Quercus coccinea Carya spp. Liriodendron tulipifera Amelanchier arborea Ilex opaca Vaccinium spp.

(CEGL006919)

American Beech - Red and White Oak - Tulip Tree Forest

Mid-Atlantic Mesic Mixed Hardwood Forest

(upland slope, mesic)

(Fagus grandifolia Quercus (alba, rubra) - Liriodendron tulipifera/ (Ilex opaca var. opaca)/ Polystichum arcostichoides)

Fagus grandifolia- Quercus rubra- Quercus alba

• • • • • • • •

(CEGL006075) • • •

Box Elder Forest

Box-elder Floodplain Forest

(lowland, riparian edge) (Acer negundo) (CEGL005033)

Acer negundo Temporarily Flooded Forest

• • • • • •

Fagus grandifolia Liriodendron tulipifera Quercus alba Cornus florida Ilex opaca Viburnum acerifolium arthenocissus quinquefolia Podophyllum peltatum Polygonatum biflorum Carex laxiculmis Polystichum arcostichoides

• •

Acer saccharinum Liquidambar styraciflua Platanus occidentalis Robinia pseudoacacia Ulmus americana Lindera benzoin

• • • • •

• • • • • • • • • • •

Nyssa sylvatica Fraxinus americana Cornus florida Asimina triloba Euonymus americana Uvularia perfoliata Liquidambar styraciflua

Liriodendron tulipifera Celtis laevitgata Acer rugbrum Carya cordiformis Fraxinus pennsylvania Juglans nigra Carpinus caroliniana Morus rubra Populus deltoidess Agertina altissima Boehmeria cylindrical Polygonum virginianum

SENSITIVE BUT UNCLASSIFIED

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix G: Existing Native Plant Community Summary

Plant Community Name

Environmental Setting

Status

Range

Other

American Beech Red and White Oak - Tulip Tree Forest

Steep ravine slopes and bluffs in dissected terrain of the inner coastal plain and outer piedmont. Mesic to submesic, extremely acidic, infertile soils, low cation and base saturation levels. Favors northerly aspects. Common on dissected landscapes of the inner coastal plain and fall-line zone of the piedmont, but occurs in progressively smaller and more isolated patches westward in the piedmont, typically on steep cut-slopes on the outside of meander bends in large creeks and small rivers.

G4

DC, DE, MD, NJ, VA

Fagus indicates fire suppression or habitats sheltered from fire. Similar to Mesic Mixed Hardwood Forests, but on drier, steeper sites with less mesophytic plants and more ericaceous plants. Fagus grandifolia and Kalmia latifolia on north-facing slopes; white oak, red oak and hickory on south-facing slopes. Moderate classification confidence.

Mesic to sub-mesic slopes or gentle gradients. Ravines in dissected topography are particularly typical. Well-drained, acidic sandy and silt loams derived parent material of low to moderate fertility.

G5

DC, DE, MD, NJ, NY, PA, VA

Vines are common. In the southern range, Oxydendrum arboretum and Vitis rotundifolia may be conspicuous members of the understory. Coastal plain with stands dominated by Ilex opaca, while piedmont has sparse Ilex. Lacks lush herb layers. Moderate classification confidence.

Stands occur on large rivers in the active floodplain and on sandbars, and may form farther from the riverfront following disturbance. Occurrences are mostly on higher floodplain terraces with less rocky soils which were used for agriculture or habitation. They are typically temporarily flooded in the spring and have sandy soils. In Kentucky, these forests may also occur in old fields.

G4

AL, AR, DC, DE, GA, IA, KY, LA, MD, MO, MS, NJ, NY, OK, PA, SC, SD , TN, TX , VA, WV

This semi-open to closed-canopy forest is found on floodplains in the southern, eastern, and midwestern United States. The shrub and herb layers range from sparse to relatively lush, and the vine component often is heavy. The herb layer consists of a mixture of weedy exotics and native floodplain species. This type is an early successional community that arises from natural and cultural disturbances on floodplains. Stands where occasional flash floods that create extensive open alluvial deposits may be colonized by this type.

(upland slope, mesic)

American Beech Red and White Oak - Tulip Tree Forest (upland slope, mesic)

Box Elder Forest (lowland, riparian edge)

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix G: Existing Native Plant Community Summary

Plant Community Name

Association

Alliance

Dominant and characteristic species

Other species

Green Ash - Black Walnut and American Sycamore Forest

Green Ash - Mixed Hardwood Floodplain Forest

• • •

Fraxinus pennsylvanica - (Juglans nigra, Platanus occidentalis) Forest

Acer saccharinum Betula nigra Fraxinus pennsylvanica Juglans nigra Platanus occidentalis Carpinus caroliniana Cornus amomum, Lindera benzoin Podophyllum peltatum Symplocarpus foetidus

(lowland, riparian edge)

Fraxinus pennsylvanica Ulmus americana Celtis (occidentalis, laevigata) Temporarily Flooded Forest

Acer rubrum Liquidambar styraciflua Nyssa sylvatica

• • • •

• • • •

(CEGL006575) • • Red Maple - Blackgum Forest (lowland, wetland)

Wetland data pending

Acer rubrum Nyssa sylvatica Saturated Forest

• • •

• •

• • • •

Ageratina altissima var. altissima Parthenocissus quinquefolia Toxicodendron radicans

Nyssa biflora Alnus serrulata Ilex opaca Photinia pyrifolia Ilex verticillata Osmunda cinnamomea Osmunda regalis Sphagnum spp.

NOTES AND KEYS: Rank Descriptions G1 - Critically imperiled globally; G2 - Imperiled globally; G3 - Rare or uncommon; G4 - Widespread, abundant, and apparently secure, but with cause for long-term concern; G5 - Demonstrably widespread, abundant, and secure; G? - Unranked; GH - Historic; GX - Extinct; GC - Planted/cultivated vegetation; GW - Ruderal vegetation, or vegetation dominated by invasive alien species; GM - Vegetation resulting from the management or modification of natural vegetation, it is readily restorable by management or time, and/ or the restoration of ecological processes. CEGL Number- unique identification number for plant communities extablished from the Central Ecology International Vegetation Classification system

SENSITIVE BUT UNCLASSIFIED

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix G: Existing Native Plant Community Summary

Plant Community Name

Environmental Setting

Status

Range

Other

Green Ash - Black Walnut and American Sycamore Forest

These floodplain forests occur behind levees and on low terraces or mid terraces that are flooded annually for short durations (less than one week per year). It also occurs on islands, bars, and mid-terrace shorelines. The water table is high for the majority of the growing season. Soils are generally silts, sandy loams, or clay loams but can have coarser substrates where floodwater velocity is higher.

GNR

DE, MD , NJ, NY, PA

This is a green ash - mixed hardwood floodplain forest of the northern Piedmont in the midAtlantic eastern United States. Diagnostic features of this floodplain forest include the presence of Juglans nigra and rich herbs.

These wetland forests occur where surface water is seldom present, but the substrate is saturated to the surface for extended periods during the growing season, and include forested acidic seeps on hilldies or streamheads, on edges of floodplains, and other pooly drained depressions. Individual occurrences of these forests tend to be small in extent, and can provide habitat for rare species.

Wetland data pending

Entire SE US

(lowland, riparian edge)

Red Maple - Blackgum Forest (lowland, wetland)

NOTES AND KEYS:

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

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Appendix H

Existing Native Plant Community Classification Methodology

The following methodology, designed by Andropogon Associates, provides a means of identifying and categorizing the existing forest stands of St. Elizabeths Campus. The identification of existing plant communities on St. Elizabeths West Campus was based on several site observations and descriptions of plant communities from NatureServe. NatureServe is a non-profit organization that is an umbrella organization that has compiled vegetation data, such as plant community data, from several state natural heritage member programs within a web-based information resource called NatureServe Explorer. These communities are also defined by the International Classification of Ecological Communities: Terrestrial Vegetation of the United States (Grossman et al. 1998) and the Ecological Systems of the United States: A Working Classification of U.S. Terrestrial Systems (Comer et al. 2003). The descriptions provided by NatureServe were used to match forest stands on the campus with these classified communities based on the raw data collected from 3 site visits. The methodology for pairing NatureServe data with specific site observations was adopted from NatureServe’s methodology for Classification of Standard Ecological Units.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix H: Existing Native Plant Community Classification Methodology

Stand Delineation Before site visits were performed, estimates about forest stand boundaries were analyzed with ArcGIS to identify representative stands on the campus. Investigations to identify every plant community on the campus was beyond the scope of this document. (Forest stands are defined by Oliver and Larson (1996) as a spatially continuous group of trees and associated vegetation having similar structures and growing under similar soil and climatic conditions.) The information/data used to estimate the forest stand boundaries prior to visiting the site includes; Successional age (historical photographs were used to determine age since last disturbance, severity of disturbance and research on successional patterns within this regional context) and Physiography (ArcGIS- soils, slope, hydrology, aspect). After the site visits, data collected on vegetation composition was also used to finalize/delineate stand boundaries based on dominate species and stand boundaries were finalized in ArcGIS based on site observations.

Site Visits Three site visits were performed for the purposes of evaluating the existing forest’s condition and classifying forest communities. Site Visit Dates and Attendees: 1. 08/04/2009 • Carol Franklin (Andropogon Associates, Founding Partner, RLA), • Emily McCoy (Andropogon Associates, Landscape Designer, BS Ecology, MLA) • Jason Lubar (Associate Director of Urban Forestry, The Morris Arboretum of the University of Pennsylvania, ISA Board Certified Master Arborist) 2. 08/27/2009 • Emily McCoy • Todd Montgomery (Andropogon Associates, Landscape Designer, BA Environmental Studies, MA, MLA) 3. 10/19/2009 • Laura Hansplant (Andropogon Associates, BLA, MLA, RLA) • Emily McCoy • Dr. Roger Latham (Continental Conservation, Ph.D Biology, Certified Ecologist)

SENSITIVE BUT UNCLASSIFIED

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix H: Existing Native Plant Community Classification Methodology

plant community classification During each site visit, random sample points were chosen within locations determined as being representative stands. Site visits 1 and 2 utilized the quadrant method, collecting data within a 50’ X 50’ grid (the minimum sample plot dimensions suggested for such inquiries) at 5 different points. On site visit 3, the transect method was used to cover the entire site within the limitations of time. The following types of data were collected: 1.

2.

3.

5. 6.

General Site Characteristics • Latitude and Longitude • Slope • Aspect • Elevation Soil Characteristics • Natural or Fill • Windthrow • Erosion, sedimentation, slumping Hydrological Characteristics • Surface drainage • Bank conditions- Bank erosion potential- high, medium low • Runoff from another site Habitat • Within bald eagle zone • Evidence of animal nesting, browsing, etc. Vegetation and Stand Characteristics • Species Composition • Species name • Dominant • Vegetation type- overstory, midcanopy, understory, ground layer • Health- Excellent, Good, Fair, Poor • Disease present • Dieback • Diameter (DBH) • Height Class • Crown condition • Age • Canopy size • Even aged or uneven aged stand • Describe successional stage • Cover Class- canopy • Litter type • Presence of sprouts, saplings and/ or seeds and species if known • Degree of disturbance- invasives, soil erosion • Invasive species • Vegetation type- overstory, midcanopy, understory, ground layer • Trees that can be transplanted • Trees that must be protected SENSITIVE BUT UNCLASSIFIED

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• Soils that need to be protected The information stated above was collected for all five quadrats. For the transect method, only dominant species and general site conditions were identified. This information was collectively used to define the plant communities for each forest stand.

SENSITIVE BUT UNCLASSIFIED

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Appendix I

Existing Forest Assessment Methodology

An assessment to evaluate each forest stand was designed to define culturally significant, high quality and high functioning forests by Andropogon Associates. The purpose of the assessment is to help identify areas that need to be protected and/or mitigated during the construction of the DHS consolidation. In addition, areas that have severe disturbances and dominance of invasive species were identified for targeted rehabilitation. Based on the current research about the historical campus and forest health, five criteria were chosen to evaluate each stand. Stands were delineated using environmental characteristics and disturbance intervals. It must be noted that although the stands graphically appear as solid lines, the separation between each stand is not that black and white, within each boundary a mix of species from the various forest associations may occur.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix I: Existing Forest Assessment Methodology

1. Cultural Significance Cultural significance has been defined by Heritage Landscapes within their Cultural Landscape Report (3. O’Donnell, Patricia M., Heritage Landscapes LLC and Robinson Judith, et al, Robinson & Associates, 2009). The report reiterates that all landscape features present during the period of significance for the campus (before 1937), including west-facing forested slopes are culturally significant. These features were digitized in GIS by Andropogon Associates then given a weight of 1 . a. Sources i. Final Master Plan (JLL) and Cultural Landscape Report-Contributing, character-defining and contributing resources as defined by the CLR, Heritage Landscapes including west facing slopes and forested areas in 1937 ii. National Register/ National Historic Landmark and Secretary of Interior’s Standards for the Treatment of Cultural Landscapes iii. Aerial photographs from Heritage Landscapes, which indicate historic, intact forest from the significant historical period iv. ArcGIS (west facing slope analysis) v. Andropogon field work b. Weight i. 0= none ii. 1= CLR and/ or SIS and/ or NPS

2. Age (Successional) Due to the historical significance of St. Elizabeths Campus, historical data was readily available. The age of each stand was determined by using aerial photographs and site drawings from 1872-2009. These were georeferenced in GIS and traced to determine the age of each forest stand (for more information about this methodology, please refer to Appendix K). In concert with this information, Oliver and Larson’s descriptions of forest stands were used to confirm each assessment (Oliver and Larson, 1996). a. Sources i. Cultural Landscape Report ii. Historical documents (aerials and site plans) iii. 1937 Campus Land Use Plan iv. USFS v. Stand Dynamics, Oliver and Larson, 1996. vi. AA field work

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b. Weight i. 0 = Young (approx. 0-30 years) (Stand-replacing disturbance and Stand-initiation) ii. 0.50 = Moderately young (approx. 30-70 years) (Stem-exclusion (‘Pole Stage’)) iii. 1 = Mature (approx. 70-137) (Understory reinitiation) 3. Health/ Integrity The criteria for the health assessment was based on several sources. The main purpose of this assessment was to identify forests stands that were on a “good trajectory,” and supporting high biodiversity, a healthy ground layer (soils and vegetation), high regeneration of native plants with minimum invasive species. It is assumed that such a healthy forest stand would need minimal intervention in order to be a high-functioning forest stand. a. Sources i. USDA Forest Health Monitor Protocol http://fhm.fs.fed.us/ii. Andropogon Associates field work

b. Weight i. 0 = low quality woodlands (low quality soils, low biodiversity, low regeneration, high invasive plant cover, poor trajectory) ii. 0.5 = medium quality woodlands iii. 1 = high quality woodlands (high quality soils, high biodiversity, high regeneration, low invasive plant cover, excellent trajectory) 4. Rarity/ Conservation Status Rarity/ Conservation status was used to determine rare or threatened plant communities on the campus. The Washington DC metro area is an ecologically rich and unique community. Over the years, intense development has eliminated these rare and unique plant communities (see Vanishing Flora of Washington and Vicinity: Three Centuries of Botanical Exploration in Alexandria, Virginia by the Botanical Society of Washington, 2007 http://alexandriava.gov/uploadedFiles/recreation/info/Vanishing%20Flora%20of%20Washington%20 and%20Vicinity.pdf ) While field identification of these rare and endangered plant species would have made this assessment more robust, it was outside the scope of this project. a. Sources i. NatureServe ii. Maryland Department of Natural Resources iii. Virginia Department of Natural Resources iv. AA field work SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

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b. Weight i. Secure G5 = 0.00 ii. Apparently Secure G4= 0.50 iii. Vulnerable G3, Imperiled G2 or Critically Imperiled G1= 1

5. Habitat Value/ Carrying Capacity for Lepidopterans One important function of forests is providing habitat for animals. The population size that an environment (here a forest stand) can support is called its carrying capacity. It has been demonstrated that certain native genera of woody and herbaceous plants are capable of supporting more native wildlife than others, therefore increasing a forest’s value to wildlife or habitat value. Doug Tallamy, an entomologist at The University of Delaware, believes that insects, more specifically Lepidopterans (moths and butterflies), are good indicators of habitat value and overall biodiversity. Insects are one of the most important “machines” for harvesting and transferring plants energy to the ecosystem. Also, Lepidopterans were chosen as specific indicators of habitat value because of the amount of data available on this order of insects and because they are “disproportionately valuable sources of food for many terrestrial birds, particularly warblers and neotropical migrants of conservation concern (Tallamy, 2009 http://copland.udel.edu/~dtallamy/host/index.html )”. Doug Tallamy and his colleagues have documented hundreds of genera in their abilities to support Lepidopterans. The ranges chosen were based on approximate natural breaks within the data set. Overall, native species support far more species than non-native plants and Quercus and Prunus genera support more Lepidopterans. a. Sources i. Doug Tallamy’s research at Univ of Delaware and verbal correspondence http://copland.udel. edu/~dtallamy/host/ ii. AA field work b. Weight- average of dominant and co-dominant woody and herbaceous plants i. Low (<100 spp) = 0 ii. Medium (100-250 spp) = 0.5 iii. High (> 250spp) = 1

6. Other Environmentally Sensitive Areas (overlays) a. Eagle’s nest buffer i. Sources: Master Plan, NPS b. Wetland area i. Sources: Master Plan and Greenehorne and O’Mara

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Appendix J

Maryland & Virginia’s Invasive Species List


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x J : M a r y l a n d & V i r g i n i a ’s I n v a s i v e S p e c i e s L i s t

Invasive Alien Plant Species of Virginia

Department of Conservation and Recreation Division of Natural Heritage 217 Governor Street Richmond, Virginia 23219 (804) 786-7951 http://www.state.va.us/dnh/

Virginia Native Plant Society Blandy Experimental Farm 400 Blandy Farm Lane, Unit 2 Boyce, Virginia 22620 (540) 837-1600 http://www.vnps.org

September 2003

Key M = Mountains P = Piedmont C = Coastal

SCIENTIFIC NAME

COMMON NAME

F = Full sun P = Part Sun S = Shade

REGION

H = Hydric M = Mesic X = Xeric

LIGHT

M

P

C

F

P

z

z

z

z

z

z

z

z

z

z

z

MOISTURE S

H

M

X

Highly Invasive Species Ailanthus altissima

Tree-of-heaven

z

z

Alliaria petiolata

Garlic mustard

z

z

Alternanthera philoxeroides

Alligator weed

Ampelopsis brevipedunculata

Porcelain-berry

Carex kobomugi

Asiatic sand sedge

Celastrus orbiculata

Oriental bittersweet

z

Centaurea dubia

Short-fringed knapweed

z

Centaurea biebersteinii

Spotted knapweed

z

z

Cirsium arvense

Canada thistle

z

z

Dioscorea oppositifolia

Chinese yam

z

z

z

Elaeagnus umbellata

Autumn olive

z

z

z

Euonymus alata

Winged burning bush

Hydrilla verticillata

Hydrilla

z

Imperata cylindrica

Cogon grass

z

Lespedeza cuneata

Chinese lespedeza

z

z

Ligustrum sinense

Chinese privet

z

z

z

Lonicera japonica

Japanese honeysuckle

z

z

z

Lonicera morrowii

Morrow's honeysuckle

z

z

Lonicera standishii

Standish's honeysuckle

z

z

Lythrum salicaria

Purple loosestrife

z

z

z

z

Microstegium vimineum

Japanese stilt grass

z

z

z

z

z z z z

z

z z

z

z

z

z

z

z

z

z z

z

z z

z

z z

z z

z

z

z z

z

z

z z

z

z

z z

z z

z z

z

z

z

z z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

SENSITIVE BUT UNCLASSIFIED

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September 2003

Key M = Mountains P = Piedmont C = Coastal

SCIENTIFIC NAME

COMMON NAME

F = Full sun P = Part Sun S = Shade

REGION M

H = Hydric M = Mesic X = Xeric

LIGHT

P

C

F

P

z

z

z

z

MOISTURE S

H

M

X

Highly Invasive Species - continued Murdannia keisak

Aneilema

Myriophyllum aquaticum

Parrot feather

z

z

z

z

z

Myriophyllum spicatum

European water-milfoil

z

z

z

z

z

Phragmites australis

Common reed

z

z

z

z

Polygonum cuspidatum

Japanese knotweed

z

z

z

z

Polygonum perfoliatum

Mile-a-minute

z

z

z

z

Pueraria montana

Kudzu vine

z

z

z

z

Ranunculus ficaria

Lesser celandine

z

z

z

Rosa multiflora

Multiflora rose

z

z

z

Rubus phoenicolasius

Wineberry

z

z

z

Sorghum halepense

Johnson-grass

z

z

z

z

z

z

Acer platanoides

Norway maple

z

z

z

z

z

z

Agropyron repens

Quack grass

z

z

z

z

z

z

Agrostis tenuis

Rhode Island bent-grass

z

z

z

z

z

Akebia quinata

Five-leaf akebia

Albizia julibrissin

Mimosa

Allium vineale

z

z z

z

z z

z

z

z

z

z z

z

z z

z

Moderately Invasive Species

z

z

z

z

z

z

z

z

z

z

z

Wild onion

z

z

z

z

z

z

Artemisia vulgaris

Mugwort

z

z

z

z

z

z

Arthraxon hispidus

Jointed grass

z

z

z

z

z

Arundo donax

Giant reed

z

z

z

z

Berberis thunbergii

Japanese barberry

z

z

z

z

z

Carduus nutans

Musk thistle

z

z

z

z

Cassia obtusifolia

Sickle pod

z

z

z

z

z

z

Centaurea jacea

Brown knapweed

z

z

z

z

z

z

Cirsium vulgare

Bull-thistle

z

z

z

z

Convolvulus arvensis

Field-bindweed

z

z

z

z

Dipsacus laciniatus

Cut-leaf teasel

z

Dipsacus sylvestris

Common teasel

z

z

z

z

Egeria densa

Brazilian water-weed

z

z

z

z

Euonymus fortunei

Wintercreeper

z

z

z

z

z

z

z

z z

z z

z

z

z

z

z z z z

z

z z

z

z

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September 2003

Key M = Mountains P = Piedmont C = Coastal

SCIENTIFIC NAME

COMMON NAME

F = Full sun P = Part Sun S = Shade

REGION

H = Hydric M = Mesic X = Xeric

LIGHT

M

P

C

F

P

z

z

z

z

z

z

z

z

z

z

z

z

MOISTURE S

H

M

X

Moderately Invasive Species - continued Festuca elatior (F. pratensis )

Tall fescue

Foeniculum vulgare

Fennel

Glechoma hederacea

Gill-over-the-ground

Hedera helix

English ivy

Holcus lanatus

Velvet-grass

z

z

Humulus japonicus

Japanese hops

z

Ipomoea hederacea

Ivy-leaved morning-glory

z

Ipomoea purpurea

Common morning-glory

Iris pseudacorus

Yellow flag

Ligustrum obtusifolium

Blunt-leaved privet

Lonicera maackii

Amur honeysuckle

z

z

Lonicera tatarica

Tartarian honeysuckle

z

z

Lysimachia nummularia

Moneywort

z

z

Melia azedarach

China-berry

z

z

z

z

z

Paulownia tomentosa

Princess tree

z

z

z

z

z

z

Phleum pratense

Timothy

z

z

z

z

z

z

Phyllostachys aurea

Golden bamboo

z

z

z

z

z

Poa compressa

Canada bluegrass

z

z

z

z

z

z

Poa trivialis

Rough bluegrass

z

z

z

z

z

z

z

z

Polygonum cespitosum

Bristled knotweed

z

z

z

z

z

z

z

z

Populus alba

White poplar

z

z

z

z

z

z

Rumex acetosella

Red sorrel

z

z

z

z

z

z

Rumex crispus

Curled dock

z

z

Setaria faberi

Giant foxtail

z

z

z

z

Spiraea japonica

Japanese spiraea

z

z

Stellaria media

Common chickweed

z

z

z

Veronica hederifolia

Ivy-leaved speedwell

z

z

z

Wisteria sinensis

Chinese wisteria

z

z

Xanthium strumarium

Common cocklebur

z

z

z

z z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z z

z

z z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

z

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September 2003

Key M = Mountains P = Piedmont C = Coastal

SCIENTIFIC NAME

COMMON NAME

F = Full sun P = Part Sun S = Shade

REGION

H = Hydric M = Mesic X = Xeric

LIGHT

M

P

C

F

P

MOISTURE S

H

M

X

Occasionally Invasive Species Agrostis gigantea

Redtop

z

z

z

z

z

z

Ajuga reptans

Bugleweed

z

z

z

z

z

z

Arrhenatherum elatius

Oatgrass

z

z

z

z

z

z

Commelina communis

Common dayflower

z

z

z

z

z

z

Conium maculatum

Poison hemlock

z

z

z

z

z

z

Coronilla varia

Crown-vetch

z

z

z

z

Dactylis glomerata

Orchard grass

z

z

z

z

z

z

Elaeagnus angustifolia

Russian olive

z

z

z

z

z

z

Elaeagnus pungens

Thorny elaeagnus

z

z

z

z

Eragrostis curvula

Weeping lovegrass

z

z

z

Euphorbia esula

Leafy spurge

z

z

Ipomoea coccinea

Red morning-glory

z

z

z

z

Lapsana communis

Nipplewort

z

z

z

z

Lespedeza bicolor

Shrubby bushclover

z

z

z

z

z

z

Lonicera fragrantissima

Sweet breath of spring

z

z

z

Lonicera x bella

Bell's honeysuckle

z

z

z

z

z

z

Lotus corniculatus

Birdsfoot trefoil

z

z

z

z

z

z

Melilotus alba

White sweet clover

z

z

z

z

z

z

Melilotus officinalis

Yellow sweet clover

z

z

z

z

z

z

Miscanthus sinensis

Silver grass

z

z

z

z

z

z

Morus alba

White mulberry

z

z

z

z

z

z

Pastinaca sativa

Wild parsnip

z

z

z

z

z

z

Perilla frutescens

Beefsteak plant

z

z

z

Trapa natans

Water chestnut

Ulmus pumila

Siberian elm

z

z

z

z

Viburnum dilatatum

Linden viburnum

z

z

z

z

Vinca minor & V. major

Periwinkle

z

z

z

z

Wisteria floribunda

Japanese wisteria

z

z

z

z

z

z

z z

z

z

z

z z

z

z

z

z

z z

z

z

z

z

z z

z

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About the List This advisory list is published by Virginia Department of Conservation and Recreation (VDCR) to inform land managers of potential risks associated with certain plant species known to exhibit invasive behavior in some situations. The list is not regulatory in nature, and thus does not prohibit the use of the plant species listed. VDCR and Virginia Native Plant Society use detailed criteria to assess the invasiveness of a plant. Factors used to rank each species include: cumulative impacts on natural areas; impacts on other species; potential to disperse and invade natural landscapes; distribution and abundance; and difficulty to manage. Invasiveness Ranking Highly invasive species exhibit the most invasive tendencies in natural areas and native plant habitats. They may disrupt ecosystem processes and cause major alterations in plant community composition and structure. They establish readily in natural systems and spread rapidly. Moderately invasive species may have minor influence on ecosystem processes, alter plant community composition, and affect community structure in at least one layer. They may become dominant in the understory layer without threatening all species found in the community. These species usually require a minor disturbance to become established. Occasionally invasive species generally do not affect ecosystem processes but may alter plant community composition by outcompeting one or more native plant species. They often establish in severely disturbed areas. The disturbance may be natural or human origin, such as icestorm damage, windthrow, or road construction. These species spread slowly or not at all from disturbed sites. Regions For the purpose of this list, the state has been divided into three regions: Coastal Plain, Piedmont, and Mountains. The Coastal Plain and Piedmont regions follow conventional physiographic province boundaries. The Mountain region combines the Blue Ridge, Ridge and Valley, and Appalachian Plateau physiographic provinces. Habitat Requirements The categories for light and soil requirements are very broad and are only meant to give general indication of habitat adaptations for these plants.

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Invasive Species of Concern in Maryland

HOME About MISC Calendar of Events Invader of the Month In the News Invasive Species of Concern in Maryland

* Red Alert species: Species not yet established in Maryland but considered to be of high risk. Key Code

Scientific Name

Common Name

2

Acer platanoides

Norway Maple

2, 3

Ailanthus altissima

Tree of Heaven

2

Alliaria petiolata

Garlic Mustard

1, 3

Allium vineale

Wild Garlic

Vertebrates

2, 3

Ampelopsis brevipedunculata

Porcelain Berry

Aquatic Plants

2, 3

Artemisia vulgaris

Mugwort

Terrestrial Plants

2

Berberis thunbergii

Japanese Barberry

1, 2, 3

Carduus acanthoides

Plumeless Thistle

1, 2, 3

Carduus nutans

Musk Thistle

2

Celastrus orbiculatus

Oriental Bittersweet

2

Centaurea maculosa

Spotted Knapweed

1, 2, 3

Cirsium arvense

Canada Thistle

1, 2, 3

Cirsium vulgare

Bull Thistle

2

Elaeagnus umbellata

Autumn Olive

2

Hedera helix

English Ivy

2

Hemerocallis fulva

Daylily

1, 4

Heracleum mantegazzianum

Giant Hogweed

2

Humulus japonicus

Japanese Hops

2

Lonicera japonica

Japanese Honeysuckle

2

Lonicera maackii

Amur Honeysuckle

2

Lonicera morrowi

Morrow's Honeysuckle

2

Lonicera tatarica

Tartarian Honeysuckle

1, 2

Lythrum salicaria

Purple Loosestrife

2

Microstegium vimineum

Japanese Stiltgrass

2

Miscanthus sinensis

Eulalia

2, 3

Perilla frutescens

Perilla

1, 2, 3

Phragmites australis

Phragmites

2

Polygonum cuspidatum

Japanese Knotweed

Insects Other Invertebrates

Viruses, Fungi and Other Organisms

Information and Resources

mdinvasivesp.org/list_terrestrial_plants.‌

Details

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Key Codes * Red Alert species: Species not yet established in Maryland but considered to be of high risk. 1. Currently Regulated by state and/or federal law 2. Widely recognized by biologists and natural resource managers to degrade natural resources and/or negatively impact native species 3. Known to have a negative economic impact on agricultural or natural resources 4. Known or potential negative impacts on human (or animal) health

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Appendix A

Forest Age Methodology

Determining forest age can aid in identifying historically significant forest stands, group and map stands based on age and help determine disturbance severity to a forest stand. Andropogon Associates developed a GIS-based analysis to determine forest stand age based on a series of aerial photographs and historical surveys that date back to 1872, provided by Heritage Landscapes.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix A: Forest Age Methodology

The approximate age of the forest stands on St. Elizabeth’s West Campus were derived through a GIS-based raster analysis that utilized a series of historical aerial photographs and surveys provided by Heritage Landscapes. There were 8 surveys and photographs dating back to 1872, ranging from 6 to 40 years apart. The largest age gap in the photographs occurred from 1948 to 1908. Each photograph and survey was orthorectifed to a common geographic coordinate system. The limits of the forest was digitized into a GIS vector layer, and then converted to two raster layers for each year. The cells of the first raster were reclassified to values of zero where no forest was present. Where forest was present, the cells were given the value of the age range of the next sequential photograph. For example: the 1978 aerial was given an age range of 10, because the next sequential photograph was taken in 1988. The cells of the second binary raster for each year were given values of 0 where no forest was present and values of 1 within the forest extent. The binary raster is needed to mathematically account for forest that was cut, and then re-grown. Once these raster layers were compiled for each year, a sequential raster calculation was performed, which added the earliest age difference raster to the next, then multiplying the result by the corresponding binary raster. This series function was performed until reaching present day, with the resulting raster cells indicating the approximate age of the underlying forest. It is important to note that this age calculation is approximate. It does not account for changes in the forest that may have occurred between photographs, or forest that existed prior to 1872. 2008

� (a

i =1872

i �agedifference

+ ai )×bi

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Appendix L

Morris Arboretum Cemetery Tree Guidelines

by Jason Lubar, Morris Arboretum’s Arboricultural Consultants

This guideline is accompanied with a spreadsheet that outlines the conditions for each assessed tree in the cemetery. The data is consolidated in the St. Elizabeths Tree Database- Appendices C and D. Please see the attached DVD for the Microsoft Excel, AutoCAD and ArcGIS database files for information regarding the cemetery trees tagged by Greenhorne and O’Mara and Bartlett Tree Experts. (Please note that the locations/coordinates of these trees were originally recorded by Greenhorne and O’Mara or Bartlett Tree Experts using GPS, not field survey. Therefore, the actual field locations may differ from the mapped graphic, Andropogon Associates does not guarantee these locations.)


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St. Elizabeth’s Cemetery Tree Inventory and Assessment Report Prepared by:

Jason Lubar – BCMA Morris Arboretum’s Arboricultural Consultants 9414 Meadowbrook Avenue Philadelphia, Pennsylvania 19118

Prepared for: Andropogon Associates, Ltd 10 Shurs Lane, Philadelphia, PA 19127

22 September 2009

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

BACKGROUND AND ASSIGNMENT

St. Elizabeth’s Hospital, located in Washington, D.C., was the first large-scale, federally-run psychiatric hospital in the United States. Recently, much of St. Elizabeth’s' west campus has fallen into disuse and is in serious disrepair. The Federal Government stepped in and transferred control of the western campus to the General Services Administration (GSA) in 2004. In March 2007, The Department of Homeland Security (DHS) announced that it would move its headquarters and most of its Washington-based offices to a new facility on the site. In January, 2009, DHS’s St. Elizabeth’s Final Master Plan was approved by the National Capital Planning Commission. In support of the Final Master Plan’s landscape considerations, Andropogon Associates and GSA requested the Morris Arboretum’s Urban Forestry Consultants complete a tree inventory and assessment in and adjacent to the site’s civil war era cemetery. Perkins + Will surveyed the trees around the cemetery, placed the trees’ location on a CAD plan, and placed uniquely numbered tags on the surveyed trees. Morris Arboretum’s Urban Forestry Consultants used these unique numbers to tie the tree inventory and assessment information to the trees’ location in the field.

FINDINGS & DISCUSSIONS

Detailed recommendations applicable to individual trees are made in the appended tree inventory and assessment spreadsheet. A summary of the findings and recommendations for the inventoried and assessed trees are as follows: Item (spreadsheet code)

Number of inventory items Tree Life Expectancy

Number or measurement

% of total*

289 56 26 36 1

70.8% 13.7% 6.4% 8.8% 0.2%

46

11.3% 1.2% 1.5% 8.6% 1.0%

>15 years 5-15 years <5 years dead or nearly so In-depth safety inspection needed

Tree Removal (Re ) Total

Highest priority (a ) Intermediate priority (b ) Lower Priority (c ) Trees that need a removal decision (cr in Re column)

Tree Pruning (G Pr ) Total

High priority (a1,2,3 ) Intermediate priority (b1,2,3 ) Low Priority (c1,2,3 )

408

5 6 35 4

304 0 7 297

100.0%

74.5% 0.0% 1.7% 72.8%

Table 1. Major findings expressed as a percentage of total inventoried and assessed trees. Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

TREE REMOVAL Trees identified as “A” & “B” priority removals could fall on “targets” such as the cemetery’s headstones and the access roads above and below the cemetery. “C” priority removals are trees within the woodland that do not threaten hardscapes. Anticipate that additional trees will need to be removed based on the security fence’s final location around the cemetery. Trees that are currently “C” priority removals, which could fall onto the security fence, should be proactively removed before security fence construction starts. The assessment information includes the tree’s estimated height, which should be used to guide these “C” priority removals at the appropriate time. There are eleven high priority tree removals identified by the tree assessment. Since many of these trees are hazardous, they should be considered for immediate action. Removals by Priority: Of the 408 inventoried and assessed trees, 11 trees should be removed. This group consists of 5 high-priority and 6 intermediate-priority removals. Removals are a normal part of landscape maintenance that address safety concerns as well as provide opportunities for replacement plantings. One additional tree removal may be necessary based on additional detailed inspection and testing of one tree marked “hi” on the inventory and assessment spreadsheet. High-priority removals are those that pose an immediate safety hazard due to their structural condition and location near high-traffic areas or structures, and they should be addressed as soon as possible. Trees categorized as intermediate-priority removals include trees with defects such as dead or dying trees that can fall onto less trafficked areas, and trees categorized as lowerpriority removals include dead and/or smaller trees or other trees that can fall completely within infrequently used areas. In-depth Safety Inspection: One tree, marked “hi” in the Life Expectancy column, requires an in-depth inspection to determine its safety. It is highly recommended that the safety inspection be done as soon as possible since it could represent a potential safety hazard. Although many safety hazards can be remedied by pruning or other prescriptive care, this tree may be recommended for removal. Consider Removal: In addition, 4 trees should be considered for removal. (These are marked “cr” in the “Re” column of the tree assessment spreadsheet.) Usually these are trees that do not fulfill their landscape potential because of significant loss of branches and/or other blemishes, i.e. are marginal trees not worthy of maintenance expenses. It is often advantageous to make a decision about the fate of such trees before scheduling a tree contractor for other arboriculturalrelated activities.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

Recommendations: • Address all high-priority removals as soon as possible. • Although they are less urgent, plan to address the intermediate-priority removals. • Plan on removing applicable “C” priority removals once the security fence orientation is finalized. • Decide which of the 4 trees coded as “consider removal” will be removed and schedule the others for appropriate maintenance work. • Inspect the tree marked “hi” in the Life Expectancy column. TREE PRUNING Seven trees having pruning needs that are medium priority and there are no trees with highpriority pruning needs. The specific recommendations for each tree can be found under the Specific Pruning (S Pr) column of the appended tree assessment spreadsheets. General pruning recommendations, which include both priority and amount of required pruning, are assigned by considering multiple factors. These factors include safety issues such as the severity of a defect, probability of damage or injury, and size of the branch, limb, or trunk. Priority also considers the tree’s long-term structural development and aesthetics. As in the Tree Removal section above, anticipate that, based on the security fence’s final location, additional trees will need to be pruned to alleviate hazardous conditions. Trees marked as “C” priority pruning whose parts could fall onto the security fence should be pruned before security fence construction starts. The assessment information includes the tree’s spread which can be used to guide which “C” priority pruning should be done. The three categories of general pruning requirements are:

High-priority pruning, an example would be a large, dead branch showing fungal conks located at the cemetery’s entrance. These trees would be indicated by the codes A1, A2 or A3 on the tree assessment spreadsheet. Intermediate-priority pruning, an example being a 3-inch diameter dead branch that could fall on the intermittently-used upper cemetery access road. These 7 trees are indicated by the codes B1, B2 or B3 on the tree assessment spreadsheet. Lower-priority pruning refers to trees that have some pruning needs but are located within the infrequently used woodland area. These 297 trees are indicated by the codes C1, C2 and C3 on the Tree Assessment spreadsheet. Since the woodlands are currently so infrequently used, we do not recommend doing “C” priority pruning excepting pruning which may impact the security fence.

Recommendations: • Schedule intermediate-priority pruning. • Plan on pruning applicable “C” priority removals once the security fence orientation is finalized.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

TREE LIFE EXPECTANCY Tree life expectancy is an estimation of how long the individual tree will survive given its specific set of circumstances and “normal” environmental conditions. It is a subjective judgment made by the arborist assessor about an individual tree on the tree inventory. Tree health, damage, location, and many other factors influence the decision about life expectancy. Four categories are used to designate life expectancy. The Morris Consultants found the trees within the project area to be distributed as follows: • • • • •

Tree Life Expectancy for St. Elizabeth's Cemetery Area

Dead or nearly so: 1.3% (8 trees) Less than five years: 9.7% (58 trees) Five to fifteen years: 10.9% (65 trees) Greater than fifteen years: 76.9% (460 trees) 1.2% (7 trees) require an in-depth inspection to determine life expectancy

5-15 years 13.7%

<5 years 6.4%

dead or nearly so 8.8%

In-depth safety inspection needed 0.2% >15 years 70.8%

All dead trees with targets are already recommended for removal and assigned a priority under removal recommendations. It may be prudent to proactively remove all the trees listed as having <5 year life expectancy if these trees could fall into the proposed security fence clearance zone. The assessment information includes the tree’s estimated height which should be used to guide these removals at the appropriate time. Note that trees listed for In-depth Safety Inspection were not assigned to a life-expectancy category. Tree Life Expectancy Recommendation: • If deemed appropriate, proactively remove all the trees listed as having <5 year life expectancy if these trees could fall into the proposed security fence clearance zone.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

DISCUSSIONS AND OBSERVATIONS

During the tree inventory and assessment, the assessors made the following general observations: Invasive/Exotic Trees: Invasive/Exotic trees threaten the woodlands health by reducing the amount of water, nutrients, light and space for native species and altering the soil chemistry and erodibility. Probably the best known exotic invasive tree in the U.S. that was found in the project area is the Tree of Heaven, Ailanthus altissima, which was introduced to America many years ago. Because of the aggressive characteristics of this species, we recommend that these trees be properly managed with the goal of extirpating them from the site in the future. Vines: Tree climbing vines are prevalent in the survey area, and are decreasing tree vigor and health by partially or completely covering tree canopies. Therefore, vines in the woodland should be managed to help assure tree health, structure, and longevity. Many of these vines are invasive/exotic, and should be aggressively managed. Native grape vines are causing treerelated problems as well, but due to their high wildlife value, should be appropriately managed towards the goal of having a sustainable population which minimally affects tree health. Tree Species/Age Diversity: The tree species diversity was low in the project area, with four species comprising about ½ of the inventoried/assessed trees as shown below: Common name ash ailanthus black locust black cherry

total 94 49 44 28

% of total 23.2% 12.1% 10.8% 6.9%

Since the project area is a part of the overall woodland, the species/age diversity in the project area may not fully represent overall woodland diversity, but it can be useful to guide decisions about diversity. The only chestnut oaks in the survey area are large and mature/overmature, making them highvalue trees which should be preserved. The survey area would benefit from increasing native tree species diversity, especially by planting more high-wildlife value trees such as white oaks/hickories in the future. Soil Erosion: Soil erosion is causing some trees to fail, especially around the collapsing concrete channels /culverts on the hillside. It would be beneficial to mitigate soil erosion from the slope and to remove non-functioning concrete channels.

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

Tree Insect/Disease Issues: • Red oaks: Some red oaks were exhibiting Bacterial Leaf Scorch symptoms. This disease is threatening the red oak population in this area. Because this is a chronic disease, expect that all red oaks will be declining or dead within a generation if a cure is not found. • Elms: There are American elms in this area that are threatened by Dutch Elm Disease. Anticipate that, if untreated, this species will decline and die as well, further decreasing species diversity. • Ash: Emerald ash borer (EAB) is an exotic beetle that kills native ash trees. To date, there is no effective way of eliminating them on a large scale. Many experts believe it is only a matter of time before they appear in the Washington DC area. Therefore, anticipate that all St. Elizabeth’s ash trees are at risk and, perhaps within a generation, will be extirpated from the woodland. This is significant due to the high percentage of ash in the woodlands. The canopy gaps formed by these trees’ demise will probably allow and encourage invasive/exotic plant species to become established. A woodland management plan should include replacing native canopy trees in canopy gaps to help stop invasive/exotic plants from getting a foothold. Forest Understory Diversity: Although it was not part of our assignment, the assessors noticed that the understory diversity (shrub, ground plane plants) is very low in the project area, probably due to excessive deer browse. Most understory plants seen during the tree assessment (summer 2009) are invasive/exotic, excepting pawpaw’s (Asimina triloba) which are well-represented throughout the woodland.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

22 September 2009

RECOMMENDATIONS SUMMARY

Tree Removals: • Address all high-priority removals as soon as possible. • Although they are less urgent, plan to address the intermediate-priority removals. • Plan on removing applicable “C” priority removals once the security fence orientation is finalized. • Decide which of the 4 trees coded as “consider removal” will be removed and schedule the others for appropriate maintenance work. In-depth Safety Inspections: • Carry out inspections on the tree marked “hi” in the Life Expectancy column to determine its safety. Tree Pruning: • Schedule intermediate-priority pruning. • Plan on pruning applicable “C” priority removals once the security fence orientation is finalized. Tree Life Expectancy Recommendation: • If deemed appropriate, proactively remove all the trees listed as having <5 year life expectancy if these trees could fall into the proposed security fence. Periodic Inspection: • The inventoried and assessed trees should be periodically inspected to identify hazardous conditions and other tree management needs, especially after the security fence is installed. Invasive/Exotic Trees: • Properly manage Tree of Heaven, Ailanthus altissima, with the goal of extirpating them from the site in the future. Vines: • Aggressively manage invasive/exotic vines. Native grape should be appropriately managed towards the goal of having a sustainable population which minimally affects tree health. Tree Species/Age Diversity: • Plan to increase native tree species diversity in the woodlands, especially by planting more high-wildlife value trees such as oaks/hickories. Soil Erosion: • Mitigate soil erosion from the slope in an ecologically sensitive way. Woodland Management Plan: • Adopt and implement a woodland management plan to help assure a healthy and sustainable woodland at St. Elizabeth’s. Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n St. Elizabeth’s 2009 A p p e n Cemetery d i x L : –MTree o r rInventory i s A r band o r eAssessment t u m C e m e t e r y T r e e G u i d22 e lSeptember ines

ASSUMPTIONS AND LIMITING CONDITIONS

Limited Scope: Information gathered and presented in this report represents conditions at the time of the inspection visit and is based on a systematic visual inspection of the above ground parts of the tree from the ground. No portion of the underground root system was inspected during the site visits. Tree conditions can degrade or change due to many reasons such as progressive decay, storm, and/or mechanical injury. Even healthy sound trees constitute some risk. Most trees, especially older trees, have defects. Not all trees with defects should be considered unreasonable risks. The tree inspection and assessment is designed to identify those trees that have warning signs of structural weakness. There may be inventoried trees with hidden defects that may not have been noted in the assessment. Do not assume that the inspector(s) looked at trees other than those covered in this report. Species Identification: Consider all trees and shrubs as field identified. The Morris Consultants strive for accuracy; however, because of field conditions, unusual species, or the availability of discernable plant characteristics from buds, fruits, flowers, or leaves, some plant species may be misidentified.

CERTIFICATION

I certify that I am a member in good standing of the International Society of Arboriculture (ISA) and am an ISA Board Certified Master Arborist and am a member in good standing of American Society of Consulting Arborists (ASCA). I further certify that I represent the Morris Arboretum of the University of Pennsylvania and that this is my work product based on my professional judgment and current industry standards and understanding.

__________________________________ Respectfully Submitted: Jason Lubar, ISA Associate Director of Urban Forestry

__________________________ Date

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

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APPENDIX 1: TREE INVENTORY AND ASSESSMENT METHODOLOGY The tree inventory and assessment data was entered directly into a Microsoft Excel spreadsheet on a handheld PC in the field. The compiled and sorted inventory/assessment information is appended to this report as a Microsoft Excel spreadsheet. This section explains how to read and extract the spreadsheet data, because it was field recorded using codes to make data collection and sorting more efficient. Keying Inventory Information to the Tree Location: A unique inventory number was entered for each inventoried and assessed tree. This number was taken from the tree’s tag installed by Perkins + Will during their CAD-based tree survey of the cemetery area. This inventory number provides the connection between the recorded tree information and its physical location. Trees not surveyed by Perkins + Will but included in our spreadsheet are indicated by a letter following the Perkins + Will-assigned number. Tree Assessment Criteria - Major Categories and Overview: The tree’s information, recorded in the inventory/assessment spreadsheet, falls into several major categories: 1) Identification, 2) Size, 3) Maintenance actions and tree condition, 4) Risk assessment, and 5) Landscape usefulness. The identification information includes the inventory number (Inv #), and the tree’s common and scientific name. Size information includes tree trunk circumference (CBH), tree height (Tree Ht), and tree canopy spread (Sprd). Life expectancy (Life Exp) for the tree is estimated in a range of years (0, <5, 5 to 15, and >15). Under the "Maintenance Action" part of the inventory form is both recommended maintenance and existing conditions. Pruning and tree removals are major tree maintenance activities. Removals (Re) are categorized into priorities A, B, C, Requires a Hazard Inspection (hi), and Consider Removal (cr). General Pruning (Pr G) records priority and amount of pruning recommended, while Specific Pruning (Sp Pr) recommendations specific actions to be taken. Girdling Root (Gd Rt) details root problems visible at or above ground level. Maintenance Score (Mt Sc) describes existing problematic conditions. Cabling information records the number of cable (C) and bracing installations recommended and the number of existing cables. Form (Fm) is used to describe general aesthetic functions of trees. Blanks indicate a generally useful tree; Excellent (e) indicates exceptional trees, while Fair (f) and Poor (p) indicate diminishing quality. Pests including insects, diseases, and mites are noted when found and recognized by the arborist assessor. Further inspection and evaluation is necessary before deciding whether control is necessary. The Comments section of the inventory form contains comments related to other parts of the assessment and unusual conditions or notes. Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

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APPENDIX 2: SPREADSHEET CODES FOR THE TREE INVENTORY AND ASSESSMENT S p readsheet C odes fo r S t. E lizabeth's C em etery

H ea d ing s: Ex p la na tion a nd colum n codes (not a ll cod es m a y be used ):

Inv# = Tag number as installed by surveyor (Perkins + W ill). A number is followed by an "a" was assigned by Morris Arboretum during the survey, and these trees are near the tree # as assigned by the surveyor. Scie ntific N ame = botanical name of the tree Common N ame = common name of the tree CB H = circumference breast height in inches (4.5 feet standard measurement from the ground) multiple entries indicate the number of trunks or stems Sprd = Tree canopy spread, i.e. - the diameter in feet of the branch spread measured in 1 dimension Ht = Estimated tree height in feet Life Exp = Life expectancy in one of four ranges, in years (0 [dead or nearly so], <5, 5-15, >15)

R e = recommended for removal (Prio rity a, b, or c; cr = consider removal; hi = hazard inspection recommended) G Pr = General P runing recommendations - General (P riority A , B, or C; A mount 1, 2, or 3. N ote: "A " is highest priority pruning, "1" = greatest amount of pruning) Sp Pr = Specific P runing recommendations bbr = broken branch cd = remove codominant limb; cp = clearance pruning; cl = correct leader; cr lb = removed cracked limb; cr br = removed cracked branch; crd = crow n reduction cw = prune to clear overhead w ire; d,dw = deadw ood pruning; e = elevate limbs; e wr = end w eight reduction; h = hanging detached branch; haz b = hazardous branch; haz d = hazardous deadw ood; haz h = hazardous hanging detached branch; Ldr = leader LL= remove long limb or leader; pa = limiting paving; re hdw = remove hardware re Ldr = remove leader; re lw lmb = remove low er limb rlb = remove limb; s = remove stub; s e p = separate s hp = shape s k = prune suckers; s m d = remove small deadw ood s mL = small leader s tr, s truc = structural pruning necessary s ub = subordinate prune s ub ldr = subordinate leader t = thin branch density; tras h = trash in tree (usually plastic bags) uld = upper limb dieback v = remove vines; vpr = vista pruning or view pruning ws = w ater sprouts; xbr = remove crossing branches; G R t = Girdling Root (re = remove girdling root or roots; x = existing girdling root; po s s = possible girdling root. C = Cabling and Bracing to reinforce w eaknesses:

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

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Spreadsheet Codes for St. Elizabeth's Cemetery

Headings: Explanation and column codes (not all codes may be used): M t Sc = Maintenance Score dp = tree is planted too deep; fc = flush cuts present; gw = guy wire(s) mr = mower root damage; mt = mower or string trimmer trunk damage; op = overpruned; pp = poor pruning rcx = root collar excavation recommended s =stubs present; s b = synthetic burlap; s r = synthetic rope; tipping = branch tips improperly pruned trdam = trunk damage; Fm = Tree form (Blank = acceptable; E = excellent form; F = fair; or P = poor) Pe sts = Tree diseases or insects noted at time of survey arm = armillaria as = apple scab b = borer; bc = bark canker; bkrb = buckrub blk knot = black knot bls = bacterial leaf scorch ca = carpenter ants car = Cedar Apple Rust cs ga = Cooley Spruce Gall Aphid; de d = dutch elm disease fc = fungal conks g = gall he s = Hemlock Elongate Scale; hwa = Hemlock Woolly Adelgid; m = mites pi = Poison Ivy te nt cat = tent caterpillars twig g = twig gall Comme nts = Comments and specific directions applying to other columns, hazard inspections, or miscellaneous notes bad = basal area decay; bk = bark; br = branch; ca, cav = cavity; cd, codom = codominant stem; cf = compressed fork cr = crack running longitudinally; dam = damage; fcr = frost crack haz = hazard; lb = limb; lg = large; pr =prune; rci = root collar investigation recommended rcx = root collar excavation recommended re = remove; s m = small.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Cemetery – Tree Inventory and Assessment

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APPENDIX 3: TREE DIVERSITY The following is the tree diversity in the project area. Common name ash ailanthus black locust black cherry Kentucky coffeetree box elder maple red oak sassafras chestnut oak siberian elm elm white oak American elm black gum dead mulberry black walnut tulip poplar hackberry pignut hickory shagbark hickory Southern white oak cottonwood pawlownia post oak persimmon sweetgum black oak bur oak American beech bitternut hickory cherry mockernut hickory Norway maple willow oak black jack oak red cedar TOTAL

total 94 49 44 28 17 16 16 14 12 12 10 10 9 8 8 6 5 5 4 4 4 4 3 3 3 2 2 2 2 2 2 1 1 1 1 1 1

% of total 23.2% 12.1% 10.8% 6.9% 4.2% 3.9% 3.9% 3.4% 3.0% 3.0% 2.5% 2.5% 2.2% 2.0% 2.0% 1.5% 1.2% 1.2% 1.0% 1.0% 1.0% 1.0% 0.7% 0.7% 0.7% 0.5% 0.5% 0.5% 0.5% 0.5% 0.5% 0.2% 0.2% 0.2% 0.2% 0.2% 0.2%

406

100.0%

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Appendix M

Morris Arboretum Plateau Tree Guidelines

by Jason Lubar, Morris Arboretum’s Arboricultural Consultants

This guideline is accompanied with a spreadsheet which outlines the conditions for each tree assessed on the plateau. That data is consolidated in the St. Elizabeths Tree Database- Appendices C and D. Please see the attached DVD for the Microsoft Excel, AutoCAD and ArcGIS database files for the information regarding the plateau trees tagged by Greenhorne and O’Mara and Bartlett Tree Experts. (Please note that the locations/coordinates of these trees were originally recorded by Greenhorne and O’Mara or Bartlett Tree Experts using GPS, not field survey. Therefore, the actual field locations may differ from the mapped graphic, Andropogon Associates does not guarantee these locations.)


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St. Elizabeth’s Plateau Tree Inventory and Assessment of Selected Trees Prepared by:

Jason Lubar – BCMA Morris Arboretum’s Arboricultural Consultants 9414 Meadowbrook Avenue Philadelphia, Pennsylvania 19118

Prepared for: Andropogon Associates, Ltd 10 Shurs Lane, Philadelphia, PA 19127

30 September 2009

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

BACKGROUND AND ASSIGNMENT

St. Elizabeth’s Hospital, located in Washington, D.C., was the first large-scale, federally-run psychiatric hospital in the United States. Recently, much of St. Elizabeth’s' west campus has fallen into disuse and is in serious disrepair. The Federal Government stepped in and transferred control of the western campus to the General Services Administration (GSA) in 2004. In March 2007, the Department of Homeland Security (DHS) announced that it would move its headquarters and most of its Washington-based offices to a new facility on the site. As part of the site preparation, Bartlett Tree Experts completed a tree inventory and assessment for landscape trees on St. Elizabeth’s plateau in 2007. Bartlett’s report, Resource Conservation Enhancement – Mature Landscape Trees and Plants, rated trees by condition and recommended tree removals. For their report, many “poor” rated trees were recommended for removal assuming an elevated risk associated with the facility being populated by employees. Subsequent to their report, many hazardous and dead trees recommended for removal have been removed. Because the GSA anticipates that St. Elizabeth’s renovation will take nearly a decade and because the “plateau” trees are part of the Hospital’s historic fabric, the GSA is placing a highpriority on tree preservation during the construction phase. Andropogon Associates, who are crafting St. Elizabeth’s Landscape Master Plan, and GSA requested the Morris Arboretum’s Urban Forestry Consultants (MAUFC) review trees rated “poor” and “dead” by Bartlett. A key difference between the previous Bartlett tree assessment and the current MAUFC tree assessment is the expectation that the number and exposure of targets will not significantly increase until the site is ultimately occupied, and therefore preserving the site’s historic fabric, namely the trees, is essential at the present time. For this MAUFC survey, recommended tree hazard mitigation activities (such as tree removal, pruning or cabling) are based on the likelihood that the tree’s structural failure would impact current targets, such as buildings, roads, or other trees. Further recommendations concern treerelated risk reduction and mitigation activities to reduce a tree’s potential of structural failure to a reasonable risk given its health, condition, and location.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

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FINDINGS & DISCUSSIONS

Detailed recommendations applicable to individual trees are made in the appended tree inventory and assessment spreadsheet. A summary of the findings and recommendations for the assessed trees are as follows: Item (spreadsheet code)

Number of inventory items Number of trees that have been removed Number of trees assessed Tree Life Expectancy

Number or measurement

>15 years 5-15 years <5 years dead or nearly so

Tree Removal (Re )

Highest priority (a ) Intermediate priority (b ) Lower Priority (c ) Trees that need a removal decision (cr in Re column)

Tree Pruning (G Pr )

High priority (a1,2,3 ) Intermediate priority (b1,2,3 ) Low Priority (c1,2,3 )

Trees Cabling and Bracing (C) Highest priority (a ) Intermediate priority (b ) Lower Priority (c ) Brace

108 21 87

% of total*

100.0%

9 24 43 12

10.3% 27.6% 49.4% 13.8%

22

25.3% 2.3% 5.7% 17.2% 9.2%

2 5 15 8

57

65.5% 12.6% 21.8% 31.0%

5

5.7% 0.0% 1.1% 2.3% 2.3%

11 19 27 0 1 2 2

Table 1. Major findings expressed as a percentage of total inventoried and assessed trees.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

TREE REMOVAL Recommendations for tree removals are based on the following considerations: High-priority removals (“A”) are those that pose an immediate safety hazard due to their structural condition and location near high-traffic areas or structures, and they should be addressed as soon as possible. Intermediate-priority (“B”) removals include trees with defects such as dead or dying trees that can fall onto less trafficked areas Lower-priority (“C”) removals include dead and/or smaller trees or other trees likely to fall completely within infrequently used areas. These categories are coded as A, B and C in the “Re” (removal) column of the appended tree assessment spreadsheets. For the current assessment, trees identified as A and B priority removals are typically adjacent to roadways or could fall on “targets” such as buildings or historic structures. C priority removals are typically trees well within mown areas or that could impact low-rated targets. Removals by Priority: Of the 87 assessed trees, seven trees should be immediately removed. This group consists of two high-priority (A) and five intermediate-priority (B) removals. Since these trees are hazardous with evident targets, they should be considered for immediate action. For these trees, it is the assessors’ opinion that even ‘heroic’ tree preservation efforts would not significantly extend the tree’s health or improve their structural stability. An example of a high priority removal is tree # 309, southern magnolia, which abuts a building and whose vascular system is decimated at the tree’s base. Although this tree could be structurally stabilized by driving two telephone poles into the ground and attaching the tree to the poles using a modified cabling system, there is no method of reinvigorating the vascular system. Therefore, MAUCF has designated this tree as a high-priority removal. Consider Removal: In addition, eight trees should be considered by the GSA for removal. (These are marked “cr” in the “Re” column of the tree assessment spreadsheet.) Typically these trees have low life expectancies (less than 5 years) and a plethora of other issues that may not make them worthy of the time and expense required to extend their lives. It is often advantageous to make a decision about the fate of such trees before scheduling a tree contractor for other arboricultural-related activities such as pruning. Recommendations: • Address all high- (“A”) and intermediate- (“B”) priority removals as soon as possible. • Decide which of the eight trees coded as “consider removal” (“cr”) will be removed and schedule the others for appropriate maintenance work. TREE PRUNING General pruning recommendations, which include both priority and amount of required pruning, are assigned by considering multiple factors. These factors include safety issues such as the severity of a defect, probability of damage or injury, and size of the branch, limb, or trunk. Priority also considers the tree’s long-term structural development and aesthetics. The three assessment categories are as follows: Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

High-priority pruning, such as a large, dead branch showing fungal conks located over a building (codes A1, A2 or A3 on the tree assessment spreadsheet). Intermediate-priority pruning, such as a 3-inch diameter dead branch that could fall on a circulation roadway (codes B1, B2 or B3 on the tree assessment spreadsheet). Lower-priority pruning refers to trees that have pruning needs but are located within infrequently used areas (codes C1, C2 and C3 on the Tree Assessment spreadsheet).

Of the 87 trees assessed, 30 trees have high- or medium-priority pruning needs that should be addressed as soon as possible; a further 27 trees have lower-priority pruning needs. The specific recommendations for each tree can be found under the Specific Pruning (S Pr) column of the appended tree assessment spreadsheets. Recommendation: • Schedule trees for high- and intermediate-priority pruning soon. OTHER RECOMMENDED TREE CARE ACTIVITIES • PROPPING: Tree and branch propping is a relatively new arboricultural activity in America, although it has been used in Europe for hundreds of years. Such practices should be designed and installed by an experienced contractor. Propping, cabling, and bracing design and installation should follow ANSI A300 (Part 3) (2006) Tree Support Systems: Cabling, Bracing, Guying, and Propping standards. The chosen tree contractor should be familiar with the Best Management Practices companion publication to the ANSI A300 – (Part 3) standard. • END WEIGHT REDUCTION: It is often desirable to decrease the length of large tree limbs, especially when long branches are prone to breakage, have weak branch attachments, or the maintenance goal is to reduce the tree’s crown. End weight reduction techniques prune the main scaffold branch back to a lateral while retaining as much photosynthetic area (leaves) as possible. This technique removes the weight (which is not in the leaves and twigs but in the large diameter woody branch) from the end of the branch while retaining the branch’s ability to provide photosynthates to the remaining branch and tree. These photosynthates are vital because they are required for new growth on the reduced branch and help the tree seal the pruning cut. End weight reduction should follow the most recent ANSI A300 (Part 1) Tree, shrub, and other Woody Plant Maintenance – Standard Practices (Pruning) standards. The chosen tree contractor should be familiar with the Best Management Practices companion publication to the ANSI A300 – (Part 1) standard.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

TREE LIFE EXPECTANCY Tree life expectancy is an estimation of how long the individual tree will survive given its specific set of circumstances and “normal” Tree Life Expectancy for selected St. Elizabeth's environmental conditions. It is a Plateau Trees subjective judgment made by the arborist assessor about an individual tree on the dead or nearly tree inventory. Tree health, damage, so 14% location, and many other factors influence the decision about life expectancy. Using four categories to designate life expectancy, the Morris Consultants found the 87 assessed trees to be distributed as follows: • Dead or nearly so: 12 trees • Less than five years: 43 trees • Five to fifteen years: 24 trees • Greater than fifteen years: 9 trees

<5 years 49%

>15 years 10% 5-15 years 27%

Given that the MAUFC tree assessment consisted of trees that Bartlett identified as being in poor condition or dead and included other trees that were identified as dead or nearly so by the assessors, it was to be expected that tree life expectancies for the 87 trees would be low. All dead trees with targets are already recommended for removal and assigned a priority under removal recommendations.

DISCUSSIONS AND OBSERVATIONS

BARTLETT’S /MAUFC TREE ASSESSMENT Bartlett’s tree condition assessment and management plan was based upon appropriate tree care needs given their assignment and the prevailing condition of the trees. Morris Arboretum’s Urban Forestry Consultants corroborate the vast majority of Bartlett’s tree assessment and recommendations for the 87 trees assessed. The tree assessment should be periodically updated, especially when activity levels near the trees increase or the property is occupied by full-time tenants. MISIDENTIFIED TREES Two trees were misidentified by Bartlett in their inventory. One of these trees, #85, has incorrect information on the tree’s identification tag. Species information for these trees should be updated in the master tree database. ADDED TREES Four trees, not rated as dead or in poor condition by Bartlett, were added to this assessment by Morris Arboretum’s Urban Forestry Consultants based on visual inspection. These trees were dead or nearly so. Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

RECOMMENDATIONS SUMMARY

Tree Removals: • Address all seven high- and intermediate-priority removals as soon as possible. • Decide which of the eight trees coded as “consider removal” will be removed and schedule the remainder for appropriate maintenance work. Tree Pruning: • Schedule high- and intermediate-priority pruning soon for 30 trees. Other Tree Care Activities: • Use only contractors that have experience designing, building, and installing tree propping systems. • Use only tree contractors who have experience making proper end-weight reduction cuts. Update the tree database: • Update the tree database with the correct species name for the two misidentified trees. Remove tree #85’s tag. Periodic Inspection: • St. Elizabeth’s “plateau” trees should be periodically inspected to identify hazardous conditions and other tree management needs, especially immediately prior to occupancy by DHS.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

30 September 2009

ASSUMPTIONS AND LIMITING CONDITIONS

Limited Scope: Information gathered and presented in this report represents conditions at the time of the inspection visit and is based on a systematic visual inspection of the above-ground parts of the tree from the ground. No portion of the underground root system was inspected during the site visits. Tree conditions can degrade or change due to many reasons such as progressive decay, storm, and/or mechanical injury. Even healthy, sound trees constitute some risk. Most trees, especially older trees, have defects. Not all trees with defects should be considered unreasonable risks. Tree inspection and assessment is designed to identify those trees that have warning signs of structural weakness. There may be inventoried trees with hidden defects that may not have been noted in the assessment. Do not assume that the inspector(s) looked at trees other than those covered in this report. Species Identification: Consider all trees and shrubs as field identified. The Morris Arboretum Urban Forestry Consultants strive for accuracy; however, because of field conditions, unusual species, or the availability of discernable plant characteristics from buds, fruits, flowers, or leaves, some plant species may be misidentified.

CERTIFICATION

I certify that I am a member in good standing of the International Society of Arboriculture (ISA) and am an ISA Board Certified Master Arborist and am a member in good standing of American Society of Consulting Arborists (ASCA). I further certify that I represent the Morris Arboretum of the University of Pennsylvania and that this is my work product based on my professional judgment and current industry standards and understanding.

Jason Lubar

__________________________________ Respectfully Submitted: Jason Lubar, ISA Associate Director of Urban Forestry

9.30.2009

__________________________ Date

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

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APPENDIX 1: TREE INVENTORY AND ASSESSMENT METHODOLOGY The tree inventory and assessment data was entered directly into a Microsoft Excel spreadsheet on handheld PCs in the field. The compiled and sorted inventory/assessment information is appended to this report as a Microsoft Excel spreadsheet. This section explains how to read and extract the spreadsheet data, because it was field recorded using codes to make data collection and sorting more efficient. Tree Assessment Criteria - Major Categories and Overview: The tree’s information, recorded by Morris Arboretum’s Urban Forestry Consultants in the inventory/assessment spreadsheet, falls into several major categories: 1) Size, 2) Maintenance actions and tree condition, 3) Risk assessment, and 4) Landscape usefulness. Size information includes tree trunk circumference (CBH), tree height (Tree Ht), and tree canopy spread (Sprd). Life expectancy (Life Exp) for the tree is estimated in a range of years (0, <5, 5 to 15, and >15). Under the "Maintenance Action" part of the inventory form is both recommended maintenance and existing conditions. Pruning and tree removals are major tree maintenance activities. Removals (Re) are categorized into priorities A, B, C, Requires a Hazard Inspection (hi), and Consider Removal (cr). General Pruning (Pr G) records priority and amount of pruning recommended, while Specific Pruning (Sp Pr) recommendations specific actions to be taken. Girdling Root (Gd Rt) details root problems visible at or above ground level. Maintenance Score (Mt Sc) describes existing problematic conditions. Cabling information records the number of cable (C) and bracing installations recommended and the number of existing cables. Form (Fm) is used to describe general aesthetic functions of trees. Blanks indicate a generally useful tree; Excellent (e) indicates exceptional trees, while Fair (f) and Poor (p) indicate diminishing quality. Pests including insects, diseases, and mites are noted when found and recognized by the arborist assessor. Further inspection and evaluation is necessary before deciding whether control is necessary. The Comments section of the inventory form contains comments related to other parts of the assessment and unusual conditions or notes.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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APPENDIX 2: SPREADSHEET CODES FOR THE TREE INVENTORY AND ASSESSMENT Spreadsheet Codes for St. Elizabeth's Plateau

Headings: Explanation and column codes (not all codes may be used): Inv# = Bartlett tag number as installed during their 2007 survey Common Name = tree's common name assigned by Bartlett. Names that have been struck indicate species was misidentified by Bartlett, updated species in 'Comments' Bartlett Cond = Bartlett's condition as listed on their 2007 tree survey. "na" indicates trees added during the 9/2009 site visit Bartlett Re Note = Bartlett's removal notes as listed on their 2007 tree survey. "na" indicates trees added during the 9/2009 site visit CBH = circumference breast height in inches (4.5 feet standard measurement from the ground) multiple entries indicate the number of trunks or stems Sprd = Tree canopy spread, i.e. - the diameter in feet of the branch spread measured in 1 dimension Ht = Estimated tree height in feet Life Exp = Life expectancy in one of four ranges, in years (0 [dead or nearly so], <5, 5-15, >15) Re = recommended for removal (Priority a, b, or c; cr = consider removal; hi = hazard inspection recommended) G Pr = General Pruning recommendations - General (Priority A, B, or C; Amount 1, 2, or 3. Note: "A" is highest priority pruning, "1" = greatest amount of pruning) Sp Pr = Specific Pruning recommendations bbr = broken branch cd = remove codominant limb; cp = clearance pruning; cl = correct leader; cr lb = removed cracked limb; cr br = removed cracked branch; cr = crown reduction cw = prune to clear overhead wire; d,dw = deadwood pruning; e = elevate limbs; ele (x ) = elevate from (x ) ewr = end weight reduction; h = hanging detached branch; haz b = hazardous branch; haz d = hazardous deadwood; haz h = hazardous hanging detached branch; Ldr = leader LL= remove long limb or leader; prop = design and install prop system for branch(es) or trunk re hdw = remove hardware re Ldr = remove leader; re lw lmb = remove lower limb rlb = remove limb; s = remove stub; sep = separate sk = prune suckers; sm d = remove small deadwood smL = small leader str, struc = structural pruning necessary sub = subordinate prune sub ldr = subordinate leader t = thin branch density; trash = trash in tree (usually plastic bags) uld = upper limb dieback v = remove vines; vpr = vista pruning or view pruning ws = water sprouts; xbr = remove crossing branches; G Rt = Girdling Root (re = remove girdling root or roots; x = existing girdling root; poss = possible girdling root) C = Cabling and Bracing to reinforce weaknesses: (1st letter is Priority [a, b, or c] # indicates the number of cables required; x# = the number of existing cables in the tree; u# indicates the number of cables requiring upgrading, braces=threaded rod)

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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St. Elizabeth’s Plateau – Tree Inventory and Assessment of Selected Trees

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Spreadsheet Codes for St. Elizabeth's Plateau

Headings: Explanation and column codes (not all codes may be used): Mt Sc = Maintenance Score dp = tree is planted too deep; fc = flush cuts present; gw = guy wire(s) mr = mower root damage; mt = mower or string trimmer trunk damage; op = overpruned; pp = poor pruning rcx = root collar excavation recommended s =stubs present; sb = synthetic burlap; sr = synthetic rope; tipping = branch tips improperly pruned trdam = trunk damage; Fm = Tree form (Blank = acceptable; E = excellent form; F = fair; or P = poor) Pests = Tree diseases or insects noted at time of survey arm = armillaria as = apple scab b = borer; bc = bark canker; bkrb = buckrub blk knot = black knot bls = bacterial leaf scorch ca = carpenter ants car = Cedar Apple Rust csga = Cooley Spruce Gall Aphid; ded = dutch elm disease fc = fungal conks g = gall hes = Hemlock Elongate Scale; hwa = Hemlock Woolly Adelgid; m = mites pi = Poison Ivy tent cat = tent caterpillars twig g = twig gall Comments = Comments and specific directions applying to other columns, hazard inspections, or miscellaneous notes bad = basal area decay; bk = bark; br = branch; ca, cav = cavity; cd, codom = codominant stem; cf = compressed fork cr = crack running longitudinally; dam = damage; fcr = frost crack haz = hazard; lb = limb; lg = large; pr =prune; rci = root collar investigation recommended rcx = root collar excavation recommended re = remove; sm = small.

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

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Fagus grandifolia Ilex opaca Fraxinus americana Prunus serotina Betula nigra Picea abies Acer saccharinum Picea abies Platanus occidentalis Quercus palustris

Juglans nigra Quercus robur Halesia Acer rubrum Prunus serotina Cryptomeria japonica Aesculus x carnea Acer saccharinum Prunus serrulata Prunus serrulata Prunus serrulata Pinus strobus Quercus alba Acer saccharinum Aesculus hippocastanum Acer saccharinum Prunus serotina Fraxinus americana Prunus serrulata Prunus serrulata Acer saccharinum Magnolia grandiflora Ulmus pumila Aesculus hippocastanum Tilia cordata

114 118 120 123 124 130 132 135 144 155

164 168 171 174 194 196 202 210 216 233 234 240 246 251 270 272 278 279 284 293 301 309 315 319 320

2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 1 Dead 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 1 Dead 1 Dead 2 Poor

2 Poor 2 Poor 2 Poor 2 Poor 1 Dead 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor

2 Poor 2 Poor 1 Dead 1 Dead 2 Poor

Bartlett cond 2 Poor 1 Dead 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 1 Dead 2 Poor 2 Poor 2 Poor 4 Good 2 Poor

106

Takedown 90 167 40 Takedown 88 14 Removed Removed Takedown 134 55 Takedown 36 Takedown 50 Takedown 102 115 Takedown 150 20 Takedown 150 Takedown 30 Takedown 192 51 Takedown 52 87 77 Takedown 100 Takedown 72 Takedown 86

Takedown

Takedown Takedown Takedown Takedown Takedown Takedown

117 78 146 106 53 67 106

Takedown 60 Takedown 66 Takedown Takedown Takedown 63

20

25

66

5-15 5-15 <5 5-15 0 <5 <5

50 75 14 35 18

45 30 23 22 70 70 40 10 43 30 70 20 15 60 40 50 50 30

34 27 22 32 35 58 76 0 46 21 69 39 14 37 32 9 33 38

c

c

cr

c

<5 5-15 5-15 5-15 5-15 >15 <5 0 c <5 b <5 5-15 5-15 <5 cr 5-15 <5 a 0 c <5 cr 5-15

5-15 cr >15 <5 <5 c <5

50 >15

52 70 14 36 16

39

45 60 55 70 23 33 45

40 <5

45 46 33 79 42 24 24 60

38 <5 17 <5

cr d d,ewr d,e,h,ewr d save lower limbs

d d,ewr d,xbr,struct d,cr,ewr d,cr d,e,h d

c3 d

c3 d b2 d,cr

c2 d,v c1 d,ewr,h,v

b1 c3 c3 c2 a1 b2 a2

c3 d

b2 d,prop c2 d,ewr,v c3 d

c3 d

a2 ewr,d,prop b1 cr,d,ewr

a2 ewr,prop b1 d,h

a2 d, ewr

c3 d a2 d

b1 c2 b2 a2 c2 c1

c2 d,ewr b2 cr,d,ewr

a

>15 5-15 0 c <5 <5 cr <5 cr <5 <5 b <5 c

<5

G Pr Sp Pr a2 d

life exp Re <5

14 25

Bartlett cbh cbh cbh cbh cbh Re note 1 2 3 4 5 sprd Ht 96 47 42 Removed Takedown 52 62 45 40 Removed 178 100 90 Takedown 101 47 63 Takedown 36 48 24 15 Takedown 148 76 58 Takedown 47 24 20 Takedown 65 34 30 Takedown 79 43 55 Takedown 39 41 31 27 Takedown 161 90 110 Removed

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

Juniperus virginiana Viburnum prunifolium Acer saccharinum Ulmus procera Acer rubrum

Common name Juglans nigra Acer plantanoides Tsuga canadensis Pinus strobus Quercus alba Acer rubrum Cercis canadensis Ulmus americana Prunus serrulata Acer saccharum Acer rubrum Tsuga canadensis Quercus alba Acer saccharinum

85 97 107 108 110

inv# 3 6 33 38 40 43 45 48 57 60 66 67 70 73 x

G Rt

b1

c1

b-brace

C

APPENDIX 4: TREE INVENTORY AND ASSESSMENT SPREADSHEETS

St. Elizabeth’s Cemetery – Tree Inventory and Assessment

mr

mr

mr

f

f p

f

f

f

f

f

f

f

p

hollow at base, brown cubical rot removed removed hollow@base, re lb in tree 209

removed top removed, 1 side of tree dead from top to about 20' up removed tree leans about15 degrees w/dead root on tension side, must prop entire tree, engineer a prop long vertical split

totally hollow w/cambial colums,is an Atlantic white cedar,no targets xcept nearby trees old, splitting tree,prune deadwood, could be contender for state champ removed removed ewr all long br's, main leader is hollow,near parking lot, manage as small canopy 1/2 canopy gone, tr decaying, ewr all br's, 2 of 3 br have sharp br angles and are not attached well, main ldr thinning, may be cv. or Engler beech? declining due to wire girdling both ldrs,wait to see if cambium grows back giant wound on tr,prop lowest br, ewr lb over road to 1st sprout declining, tr cav@ 35', no targets except pipe house/gazebo @ other trees dead-it was a kwanzan cherry

removed

fungus at base one lead dead; other leader with cavity at base

Comments 25% of crown dead removed larger lead is split out and leaning, only cable is holding it up removed long vertical crack on tension side large cavity at 20 feet out in open-no tagets-totally dead long vertical splits,vigorous,1/2 of tree splitout only 1 leader alive

mostly dead no targets

Page 12 of 13

oozing canker

codom at 1', small split out, mower root damage, CBH measured @ 1' codom at 1', CBH measured @ 1' cavity at 12' large codom split at 25' much deadwood, declining dead 3 of 6 leads dead, CBH measured @ base remove dead lead large cavity backside facing wall, significant lean fungus,gummosis eastern most br has fungus and will decline soon, no targets gumosis,plum borer 20 degree lean w/uplifted soil, many wounds on tr, lvs browning sap rotting fungi bad tr rot @ base

carpenter ants black knot disease

ambrosia beetle

PI

sapsucker

Mt Sc form Pests p

22 September 2009

S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x M : Mo r r i s A r b o r e t u m P l ateau Tr e e G u i d e l i n e s

SENSITIVE BUT UNCLASSIFIED

M : 3 61


inv# 322 324 325 326 334 335 337 342 343 344 354 367 370 376 379 393 406 413 416 417 421 430 434 440 441 456 457 458 462 463 467 470 474 475 476 477 480 491 497 510 512 513 516 518 534 541 546 547 557 565 566 586 618 643

M:362

Takedown Takedown Takedown Takedown Takedown Takedown Removed Removed Takedown Takedown Takedown Takedown Takedown Takedown Takedown Takedown

na

20

85

135 71 66 68 136 101 75 104 105

60 >15

58

0 <5 <5 5-15 0 <5 5-15 0

20 35 25 50 35 40 10 25

16 16 14 45 27 24 6 7

5-15 <5 5-15 >15 <5 <5 5-15 0 0 <5 <5 <5 5-15 >15

<5 <5 <5 <5 0

20 15 18 28 70 60

70 40 50 75 90 55 55

20 35 20 20 25

15 <5 55 >15

2 47 39 34 61 56

56 56 32 52 33 62 60

22 42 15 36 2

28

47 77 30 69 72

49

21 48

21 101

30 32 52 40 30 45

42 29 40 24 24 32

5-15 <5 5-15 5-15 0 0

14 <5 70 >15 35 <5

17 63 30

c

b c

c

c c

c

cr

cr

b b

c

cbh cbh cbh cbh cbh life 1 2 3 4 5 sprd Ht exp Re 65 30 25 <5 18 6 10 <5 174 44 40 5-15 90 27 33 5-15

36 110 Takedown 72 Takedown Takedown 68 Takedown 39 77 137 Takedown 37 na 67

Bartlett Re note Takedown Takedown Takedown Takedown Removed Takedown Takedown

80 Takedown 120 Takedown 81 73 Takedown 154 72 Removed na 17 45 Takedown 46 Takedown 75 Takedown 62 Takedown 88 Takedown 9 na 33 Takedown Removed 2 Poor 87

2 Poor 2 Poor 1 Dead 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 1 Dead na 2 Poor 2 Poor 2 Poor 1 dead 2 Poor 2 Poor na 1 Dead

Bartlett cond 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor na 2 Poor na 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 2 Poor 1 Dead re haz lb,d d d,cr,h,ewr,xbr d,cr

d d v,d v,d

v,d d, ele sidewalk d,cr,props d,h,cr d

c2 d,ewr,v

a3 a2 b2 a1 b2

c1 d,cr,ewr

c2 d b2 d,v,ewr

c2 d,cr,h

c2 b2 c1 c1

c2 d,e

b2 c2 b1 b1

b2 d, ewr b2 d,cr

c2 d b2 d,cr

G Pr Sp Pr c2 d,cr,ewr

Prepared by: Jason Lubar Morris Arboretum’s Urban Forestry Consultants 9414 Meadowbrook Avenue, Philadelphia, PA 19118 215-247-5777 Extension 189

Common name Tilia americana Fraxinus pennsylvani Ulmus procera Acer saccharinum Styrax Spp. Quercus rubra Prunus species Quercus palustris Cladrastis kentukea Quercus rubra Ulmus procera Acer plantanoides ('Crimso Liquidambar styraciflua Gymnocladus dioicus Quercus palustris? Gleditsia triacanthos Aesculus hippocastanum Aesculus hippocastanum hawthorne Magnolia grandiflora Quercus phellos Cercis canadensis Acer saccharum Tsuga canadensis Morus rubra Quercus palustris Quercus prinus Quercus prinus Quercus rubra Ulmus americana Quercus rubra Quercus prinus Robinia pseudoacacia Acer negundo Acer negundo Quercus prinus Acer negundo Prunus serrulata Acer negundo Acer saccharum Ulmus procera Acer rubrum Ulmus procera bradford pear Paulownia tomentosa Paulownia tomentosa Morus rubra Acer negundo Prunus serotina Thuja occidentalis dead Quercus species Fraxinus pennsylvani Acer rubrum

St. Elizabeth’s Cemetery – Tree Inventory and Assessment

x

poss

x

G Rt

c4/c-brace

C

mr

mt

mt

p p

p p

p p p

f

p

PI borers

Comments

removed girdled only 1 colum of living tissue, no targets xcept fence, good wildlife tree only 1 colum of living tissue, no targets xcept fence, good wildlife tree beyond fence needs at least to be reduced, outside of fence cavity at base, beyond fence damaged and deer browsed dead removed removed why was this rated poor by Bartlett?

removed almost dead, small tree w/no targets construction root damage reported removed tree split, regrowing top dead, many tr wounds,declining re vines to save tree, swinging chair (overgrown)nearby covered in vines,1 leader out of 2 extent monolith removed removed huge hollow at base, either no activity in grass area or remove tree both leaders split almost to ground tree has BLS & will continue to decline old hollow on backside, tr split below hollow,tree leaning, re lowest br,monitor very large cavity at 20' one side dead, other side split scar at base, hollow trun, cavity at 7', remove low limb fell over 20' monolith re vines to save tree, elm growing near base,major leads dead, good wildlife tree dying back, rem dead to living tissue multi-cavity at base, sapsucker injury, cavities at 6' multi-cables, large codom split at 12', cavity 12' to base, split br at 250'

removed removed re low lb over walkway, 12"wide dead gap in tr @ base, 'crimson king' Acer truncatum! No targets cavity at base; mower trunk damage cavity at base and large scar on trunk

small tree, declining hollow@base,top is dead splitout and cavity at 12' removed removed

Page 13 of 13

carpenter ants

BLS

borer,sapsucker

twig gall,rust?

plum borer BLS (slight)

groundhog

Mt Sc form Pests

22 September 2009

S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x M : Mo r r i s A r b o r e t u m P l ateau Tr e e G u i d e l i n e s

SENSITIVE BUT UNCLASSIFIED

andropogon associates ltd.


Appendix N

USDA’s Non-Native Invasive Plants for Southern Forests by John Miller

Please see the USDA Forest Service website for this publication. This publication includes techniques for identifying non-native invasive plants and specific techniques for eradication of each species.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n A p p e n d i x N : U S DA’s N o n - N a t i v e I n v a s i v e P l a n t s f o r S o u t h e r n F o r e s t s

This page intentionally left blank.

SENSITIVE BUT UNCLASSIFIED

N:364

andropogon associates ltd.


Appendix O

Plant Species List for Native Plant Community Structures


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

FOREST INTERIOR For areas inside of existing forest/woodland Botanical Name

Common Name

Type

Reference Plant Community

Acer rubrum

red maple

Canopy Tree

BMO, GSB

Acer saccharum

sugar maple - heat resistant cultivar

Canopy Tree

GSB

Carpinus caroliniana

American hornbeam

Canopy Tree

BMO, GSB

Carya cordiformis

bitternut hickory

Canopy Tree

GSB

Carya glabra

pignut hickory

Canopy Tree

BMO

Carya ovata

shagbark hickory

Canopy Tree

BMO, GWM

Celtis laevigata

sugarberry

Canopy tree

GSB

Celtis occidentalis

common hackberry

Canopy Tree

GSB

Fagus grandifolia

American beech

Canopy tree

BCO, BMO, GSB

Liquidambar styraciflua

sweetgum

Canopy Tree

BMO

Liriodendron tulipifera

tulip poplar

Canopy Tree

BMO, GSB

Nyssa sylvatica

blackgum

Canopy Tree

BCO, BMO, GSB

Platanus occidentalis

American sycamore

Canopy Tree

GSB, GWM

Quercus alba

white oak

Canopy Tree

BMO, GSB, BCO, OSG

Quercus bicolor

swamp white oak

Canopy Tree

GSB

Quercus coccinea

scarlet oak

Canopy Tree

BCO, BMO

Quercus falcata

southern red oak

Canopy tree

BCO, BMO, GSB

Quercus laurifolia

laurel oak

Canopy Tree

GSB

Quercus lyrata

overcup oak

Canopy Tree

GSB

Quercus michauxii

swamp chestnut oak

Canopy Tree

GSB

Quercus nigra

water oak

Canopy tree

BCO, BMO

Quercus pagoda

cherrybark oak

Canopy Tree

GSB

Quercus phellos

willow oak

Canopy Tree

GSB

Quercus prinus

chestnut oak

Canopy Tree

BCO, GSB

Quercus rubra

northern red oak

Canopy Tree

BMO, GSB

Tilia americana

American basswood

Canopy Tree

GSB

Amelanchier arborea

common serviceberry

Und. Tree / Shrub

BCO, BMO, GSB, GWM

Chionanthus virginicus

fringetree

Understory Tree

GWM

CANOPY & EVERGREEN TREES

UNDERSTORY TREES

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:366

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Reference Plant Community

Cornus florida

dogwood

Understory Tree

BMO, GSB

Halesia carolina

Carolina silverbell

Understory Tree

GSB

Hamamelis virginiana

American witchhazel

Understory Tree

BMO, GSB

Ilex opaca (use cultivar)

American holly cultivar

Understory Tree

BCO, BMO, GSB

Magnolia virginiana

sweetbay magnolia

Understory Tree

BMO, GSB, OSG

Oxydendreum arboreum

sourwood

Understory Tree

BMO, BCO, GSB

Sassafras albidium

sassafras

Understory Tree

BCO, GSB, BMO, GWM

Vaccinium arboreum

perfoliate bellwort

Understory Tree

BMO

Asimina triloba

pawpaw

Shrub

GSB

Ceonanthus americanus

New Jersey tea

Shrub

BCO, GWM

Cephalanthus occidentalis

buttonbush

Shrub

OSG

Clethra alnifolia

summersweet

Shrub

GSB

Epigaea repens

trailing arbutus

Shrub

BCO

Euonymus americanus

bursting heart

Shrub

BMO, GSB

Fothergilla gardenii

dwarf fothergilla

Shrub

Fothergilla major

mountain witchalder, lg. fothergilla

Shrub

BCO

Gaylussacia baccata

black huckleberry

Shrub

BCO

Kalmia latifolia

mountain laurel

Shrub

BCO, GSB

Leucothoe axillaris

coast leucothoe

Shrub

GSB

Leucothoe fontanesiana

weeping leucothoe

Shrub

GSB

Leucothoe racemosa

swamp doghobble

Shrub

GSB

Lindera benzoin

spicebush

Shrub

GSB

Parthenocissus quinquefolia

virginia creeper

Vine

BMO, GSB

Pieris floribunda

mountain fetterbush

Shrub

BCO

Rhus aromatica

fragrant sumac

Shrub

BMO, GSB

Stewartia malacodendron

silky camellia

Shrub

BMO

Vaccinium angustifolium

Sheep Laurel

Shrub

BCO

Vaccinium corymbosum

lowbush blueberry

Shrub

BMO, GSB

Vaccinium pallidum

early lowbush blueberry

Shrub

BMO, GSB

Viburnum acerifolium

mapleleaf viburnum

Shrub

BMO, GSB

Viburnum dentatum

arrowwood viburnum

Shrub

BMO, GSB

Viburnum prunifolium

blackhaw

Shrub

BMO, GSB

Viburnum rafinesquianum

downy arrowwood

Shrub

BMO, GSB

SHRUBS & VINES

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O : 367


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Reference Plant Community

Aster cordifolius (Symphyotrichum cordifolium)

blue wood aster

Herbaceous

BMO

Aster divaricatus (Eurybia divaricata)

white wood aster

Herbaceous

BMO, GSB

Aster divaricatus ‘Eastern Star’ (Eurybia divaricata)

white wood aster

Herbaceous

BMO, GSB / hort.

Athyrium filix-femina

ladyfern

Herbaceous

BMO, GSB, BCO

Herbaceous

GSB

HERBACEOUS

Athyrium filix-femina var. asplenioides Carex muckingumensis

Muskingum sedge

Herbaceous

GSB

Carex pennsylvanica

Pennsylvania sedge

Herbaceous

BMO, BCO, GSB

Carex platyphylla

broadleaf (silver) sedge

Herbaceous

BMO (GSB)

Carex rosea

rosy sedge

Herbaceous

BMO (GSB)

Carex flaccosperma

thinfruit sedge, blue wood sedge

Herbaceous

GSB

Deschampsia flexuosa

crinkled hair grass

Herbaceous

BMO

Dicentra canadensis

squirrel corn

Herbaceous

GSB

Dicentra eximia

fringed bleeding heart

Herbaceous

BMO

Erythronium americanum

dogtooth violet

Herbaceous

GSB

Eupatorium coelestinum

blue mistflower

Herbaceous

GSB

Iris verna

dwarf violet iris

Herbaceous

BCO

Mertensia virginica

bluebells

Herbaceous

BMO, GSB

Onoclea sensibilis

sensitive fern

Herbaceous

BCO, GSB

Osmunda cinnamomea

cinnamon fern

Herbaceous

GSB

Osmunda cinnamomea var. cinnamomea

cinnamon fern

Herbaceous

BMO

Penstemon digitalis

penstemon

Herbaceous

GSB

Phlox divaricata

wild blue phlox

Herbaceous

GSB

Physostegia virginiana ‘Miss Manners’

obedient plant

Herbaceous

GSB

Polygonatum biflorum

Solomons seal

Herbaceous

GSB

Polystichum acrostichoides

Christmas fern

Herbaceous

BMO, GSB

Silene virginica

firepink

Herbaceous

BCO

Thelypteris noveboracensis

New York fern

Herbaceous

BCO, BMO, GSB

Tiarella cordifolia

foamflower

Herbaceous

BMO

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:368

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Reference Plant Community

Note: Meadow seeding applicable to this planting zone will include additional species

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:369


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

FOREST Edge For edges of forest/woodland, selected areas adjacent to roads or built areas, and stormwater management areas Botanical Name

Common Name

Type

ReferencePlantCommunity

Acer negundo

box elder

Canopy Tree

Acer rubrum

red maple

Canopy Tree

BMO, GSB

Acer saccharinum

silver maple

Canopy Tree

GSB

Acer saccharum (heat resistant cultivar)

sugar maple -Bonfire, Green Mountain, Legacy, Majesty, Crescendo (‘A. S. Morton’), John Pair

Canopy Tree

GSB

Betula nigra

river birch, (Dura Heat and Heritage nearer pavements/ buildings)

Canopy Tree

GSB

Carya glabra

pignut hickory

Canopy Tree

BEP

Celtis laevigata

sugarberry

Canopy tree

GSB

Celtis leav. x occ. ‘Magnifica’

Magnifica hackberry

Canopy tree

n.a. (streetside tolerant)

Celtis occidentalis ‘Prairie Pride’

Prairie Pride hackberry

Canopy Tree

GSB

Juniperus virginiana

eastern red cedar

Evergreen Tree

BEP

Liquidambar styraciflua

sweetgum

Canopy Tree

BMO

Liquidambar styraciflua - fruitless cultivar

fruitless sweetgum - Happidaze or Rotundiloba

Canopy Tree

BMO / hort.

Liriodendron tulipifera

tulip poplar

Canopy Tree

BMO, GSB, BEP

Nyssa sylvatica

blackgum

Canopy Tree

BCO, BMO, GSB, BSW

Pinus echinata

shortleaf pine

Evergreen Tree

BMO

Pinus pungens

Table Mountain pine

Evergreen Tree

BCO

Pinus rigida

pitch pine

Evergreen Tree

BMO, BCO

Pinus strobus

white pine

Evergreen Tree

BMO, GWM

Pinus taeda

loblolly pine

Evergreen Tree

BMO, GSB, GWM, BEP

Pinus virginiana

Virginia pine

Evergreen Tree

BMO, GSB, BCO, GWM, BEP

Platanus occidentalis

American sycamore

Canopy Tree

GSB, GWM

Platanus x acerifolia ‘Bloodgood’

Bloodgood Londonplanetree (or equal)

Canopy Tree

non-native, non-invasive

Populus deltoides

Eastern cottonwood

Canopy Tree

BEP

Quercus alba

white oak

Canopy Tree

BMO, GSB, BCO, GWM, BEP

Quercus bicolor

swamp white oak

Canopy Tree

GSB, BEP

Quercus coccinea

scarlet oak

Canopy Tree

BCO, BMO

Quercus falcata

southern red oak

Canopy tree

BCO, BMO, GSB

Quercus laurifolia

laurel oak

Canopy Tree

GSB

CANOPY & EVERGREEN TREES

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:370

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

ReferencePlantCommunity

Quercus phellos

willow oak

Canopy Tree

GSB

Quercus prinus

chestnut oak

Canopy Tree

BCO, GSB, BEP

Quercus rubra

northern red oak

Canopy Tree

BEP

Quercus stellata

post oak

Canopy Tree

BEP

Quercus velutina

black oak

Canopy Tree

BEP

Robinia pseudoacacia

Black locust

Canopy Tree

BEP

Taxodium distichum

bald cypress

Canopy tree

GSB, BEP

Tilia americana

American basswood

Canopy Tree

GSB

Tilia americana x eucholora ‘Redmond’

Redmond Linden

Canopy Tree

n.a. (streetside tolerant)

Ulmus americana - resistant cultivar

American Elm: Liberty, Princeton, Jefferson, New Harmony, or Valley Forge

Canopy Tree

n.a. (streetside tolerant)

Amelanchier arborea

common serviceberry

Under. Tree/Shrub

BCO, BMO, GSB, GWM

Amelanchier canadensis

Canadian serviceberry

Under. Tree/Shrub

BSW

Amelanchier leavis ‘Cumulus’

Cumulus shadblow (upright, treeform)

Understory Tree

n.a. (streetside tolerant)

Cercis canadensis

eastern redbud

Understory Tree

BMO, GSB, GWM, BEP

Cornus florida`

flowering dogwood

Understory Tree

BEP

Chionanthus virginicus

white fringetree

Understory tree

BSW

Cornus florida

dogwood

Understory Tree

BMO, GSB

Halesia carolina

Carolina silverbell

Understory Tree

GSB

Ilex opaca (use cultivar)

American holly cultivar

Understory Tree

BCO, BMO, GSB

Juniperus virginiana

eastern redcedar

Understory Tree

BMO, GSB, GWM

Magnolia acuminata

cucumbertree magnolia

Understory Tree

n.a. (streetside salt/wet tol.)

Magnolia virginiana

sweetbay magnolia

Understory Tree

BMO, GSB, GWM, BSW

Magnolia virginiana ‘australis’

evergreen sweetbay magnolia

Understory Tree

BMO, GSB, GWM

Morus rubra

Red mulberry

Und./Sh. Tree

BEP

Ostrya virginiana

eastern hophornbeam

Und./Sh. Tree

BEP

Oxydendreum arboreum

sourwood

Understory Tree

BMO, OBF, GSB

Prunus virginiana ‘Canada Red Select’

Canada Red Select Cherry

Understory Tree

n.a. (streetside tolerant)

Sassafras albidium

sassafras

Understory Tree

BCO, GSB, BMO, GWM, BEP

common alder

Shrub/understory tree

BSW

UNDERSTORY TREES

SHRUBS Alnus serrulata

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:371


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

ReferencePlantCommunity

Aronia arbutifolia

red chokeberry

Shrub

BSW

Aronia melanocarpa

black chokeberry

shrub

n.a. (streetside tolerant)

Asimina triloba

pawpaw

Shrub

GSB

Clethra alnifolia

summersweet

Shrub

GSB

Clethra alnifolia ‘Hummingbird’

dwarf summersweet

Shrub

GSB

Cornus amomum

silky dogwood

Shrub

BEP

Fothergilla gardenii

dwarf fothergilla

Shrub

n.a. [horticultural interest]

Fothergilla major

mountain witchalder, lg. fothergilla

Shrub

BCO

Gaylussacia frondosa

blue huckleberry

Shrub

BSW

Hydrangea arborescens

wild hydrangea

Shrub

GSB

Hydrangea quercifolia

oakleaf hydrangea

Shrub

BMO

Hydrangea quercifolia cultivar

oakleaf hydrangea

Shrub

BMO / hort.

Ilex glabra

inkberry

Shrub

GSB

Ilex glabra compacta

compact inkberry

Shrub

GSB

Ilex verticillata

winterberry

Shrub

BSW

Ilex verticillata Red Sprite

dwarf winterberry

Shrub

n.a. (streetside salt/wet tol.)

Kalmia angustifolia

sheep laurel

Shrub

BSW

Kalmia latifolia

mountain laurel

Shrub

BCO, GSB

Leucothoe axillaris

coast leucothoe

Shrub

GSB

Leucothoe fontanesiana

weeping leucothoe

Shrub

GSB

Leucothoe racemosa

fetterbush

Shrub

BSW

Lindera benzoin

spicebush

Shrub

GSB

Lyonia ligustrina

maleberry

Shrub

BSW

Lyonia mariana

staggerbush

Shrub

BSW

Physocarpus opulifolius

ninebark

Shrub

BEP

Prunus caroliniana

Carolina laurelcherry

Shrub

GSB

Rhododendron calendulaceum

flame azalea

Shrub

GSB

Rhododendron catawbiense

catawba rhododendron

Shrub

BCO

Rhododendron maximum

great laurel, rosebay rhododendron

Shrub

BCO, GSB

Rhododendron periclymenoides

pinxterbloom

Shrub

BCO

Rhododendron viscosum

swamp azalea

Shrub

BSW

Rhus aromatica

fragrant sumac

Shrub

BMO, GSB, BEP

Rhus aromatica ‘Grow Low’

Grow Low fragrant sumac

Shrub

BMO, GSB/hort

Spirea alba

white meadowsweet

Shrub

GSB

Vaccinium corymbosum

highbush blueberry

Shrub

BMO, GSB, BSW

Viburnum dentatum

arrowwood viburnum

Shrub

BMO, GSB

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:372

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

ReferencePlantCommunity

Viburnum nudum

possum-haw

Shrub

BSW

Viburnum prunifolium

blackhaw

Shrub

BMO, GSB

Andropogon gerardii

big blue stem

Herbaceous

BEP

Andropogon virginicus

broom sedge

Herbaceous

BEP

Asclepias quadrifolia

four-leaved milkweed

Herbaceous

BEP

Asclepias rubra

red milkweed

Herbaceous

BSW

Aster (Symphyotrichum) novaeangliae cultivar

New England aster - Purple dome or similar

Herbaceous

n.a. (streetside tolerant)

Aster cordifolius (Symphyotrichum cordifolium)

blue wood aster

Herbaceous

BMO

Aster divaricatus (Eurybia divaricata)

white wood aster

Herbaceous

BMO, GSB

Aster ericoides (Symphyotrichum ericoides)*

white heath aster

Herbaceous

BCO, GWM

Aster novae-angliae

New England aster

Herbaceous

BEP

Baptisia australis ‘minor’

dwarf blue wild indigo

Herbaceous

n.a. (streetside tolerant)

Calopogon tuberosus

grass pink

Herbaceous

BSW

Carex crinita

fringed sedge

Herbaceous

BSW

Carex folliculata

northern long sedge

Herbaceous

BSW

Carex intumescens

swollen sedge, bladder sedge

Herbaceous

BSW

Carex lurida

sallow sedge

Herbaceous

BSW

Carex pennsylvanica

Pennsylvania sedge

Herbaceous

BMO, OBF, GSB, BEP

Carex platyphylla

broadleaf (silver) sedge

Herbaceous

BMO

Carex stricta

tussock sedge

Herbaceous

BSW

Carex vulpinoidea

fox sedge

Herbaceous

n.a. (streetside salt/wet tol.)

Carex flaccosperma

thinfruit sedge, blue wood sedge

Herbaceous

GSB

Chasmanthium latifolium

river oats, wood oats

Herbaceous

GSB

Chasmanthium latifolium

river oats

Herbaceous

BEP

Chelone glabra

white turtlehead

Herbaceous

BSW

Chrysogonum virginianum

green and gold

Herbaceous

GSB

Coreopsis tripteris

tall tickseed

Herbaceous

BEP

Coreopsis verticillata

Moonbeam or Zagreb coreopsis

Herbaceous

n.a. (streetside tolerant)

Deschampsia flexuosa

crinkled hair grass

Herbaceous

BMO

Dicentra eximia

fringed bleeding heart

Herbaceous

BMO

Dioscorea villosa

wild yam

Herbaceous

BSW

HERBACEOUS

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:373


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

ReferencePlantCommunity

Echinacea purpurea cultivar

dwarf purple coneflower

Herbaceous

GSB / horticultural

Echinacea purpurea*

purple conflower

Herbaceous

GSB

Elymus hystrix

eastern bottlebrush grass

Herbaceous

GSB, BEP

Elymus hystrix

bottlebrush grass

Herbaceous

Elymus virginicus*

Virginia wildrye

Herbaceous

GSB

Eupatorium coelestinum

blue mistflower

Herbaceous

GSB

Eupatorium purpureum

Joe-Pye Weed

Herbaceous

BEP

Geranium maculatum

spotted geranium

Herbaceous

GWM

Glyceria striata

fowl mannagrass

Herbaceous

BSW

Helianthus divaricatus

woodland sunflower

Herbaceous

BEP

Helianthus occidentalis

western sunflower

Herbaceous

BEP

Heuchera americana

American alumroot

Herbaceous

BMO

Heuchera americana cultivar

American alumroot

Herbaceous

BMO / hort,

Iris versicolor

blue flag

Herbaceous

n.a. (streetside salt/wet tol.)

Juncus canadensis

Canada rush

Herbaceous

BSW

Juncus effusus

soft rush

Herbaceous

n.a. (streetside salt/wet tol.)

Lespedeza violacea

violet bushclover

Herbaceous

BEP

Liatris spicata

dense blazing star

Herbaceous

GSB, BEP

Liatris spicata ‘Kobold’

dwarf blazing star

Herbaceous

GSB/ hort.

Lilium superbum

turk’s cap lily

Herbaceous

BSW

Maianthemum canadense

Canadian mayflower

Herbaceous

BSW

Medeola virginiana

indian cucumber root

Herbaceous

BSW

Muelenbergia capillaris

pink muhly

Herbaceous

BEP

Muhlenbergia capillaris

Purple (Pink) Muhly

Herbaceous

n.a. (streetside salt/wet tol.)

Onoclea sensibilis

sensitive fern

Herbaceous

BCO, GSB

Osmunda cinnamomea

cinnamon fern

Herbaceous

BSW

Osmunda regalis

royal fern

Herbaceous

BSW

Panicum virgatum

switchgrass

Herbaceous

GSB, BEP

Panicum virgatum cultivar

switchgrass (cultivar)

Herbaceous

GSB/hort

Phlox divaricata cultivar

wild blue phlox

Herbaceous

GSB

Physostegia virginiana

northern obedient-plant

Herbaceous

Pogonia ophioglossoides

rose pogonia

Herbaceous

BSW

Polystichum acrostichoides

Christmas fern

Herbaceous

BMO, GSB

Pycnanthemum tenuifolium

narrow-leaved mountainmint

Herbaceous

Rhexia virginica

Virginia meadow beauty

Herbaceous

BSW

Rhynchospora microcephala

small-headed beakrush

Herbaceous

BSW

Rubus hispidus

bristly dewberry

Herbaceous

BSW

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O : 3 74

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

ReferencePlantCommunity

Rudbeckia fulgida fulgida

orange coneflower

Herbaceous

horticultural

Rudbeckia hirta*

blackeyed Susan

Herbaceous

BCO, GSB, GWM

Sagittaria latifolia var. pubescens

pubescent arrowhead

Herbaceous

BSW

Schizachyrium scoparium

little bluestem

Herbaceous

BCO, BEP

Sedum ternatum

wild stonecrop

Herbaceous

BMO, GSB

Silene virginica

firepink

Herbaceous

BCO

Solidago rugosa

wrinkleleaf goldenrod

Herbaceous

GSB, BEP

Solidago rugosa ‘fireworks’

Fireworks goldenrod

Herbaceous

GSB/hort., BEP

Solidago sempervirens

seaside goldenrod

Herbaceous

for streetside salt/wet tol., BEP

Solidago uliginosa

bog goldenrod

Herbaceous

BSW

Spiranthes cernua

nodding ladies’-tresses

Herbaceous

BSW

Sporobolus heterolepis

prairie dropseed

Herbaceous

GWM

Symphyotrichum sp.

asters

Herbaceous

BEP

Symplocarpus foetidus

skunk cabbage

Herbaceous

BSW

Thelypteris noveboracensis

New York fern

Herbaceous

BSW

Thelypteris palustris

marsh fern

Herbaceous

BSW

Thelypteris simulata

bog fern

Herbaceous

BSW

Tiarella cordifolia

foamflower

Herbaceous

BMO

Tofieldia racemosa

coastal false asphodel

Herbaceous

BSW

Tradescantia virginiana

Virginia spiderwort

Herbaceous

BEP

Utricularia subulata

zigzag bladderwort

Herbaceous

BSW

Uvularia sessilifolia

wild oats, sessile bellwort

Herbaceous

BSW

Viola primulifolia

primrose-leaved violet

Herbaceous

BSW

Woodwardia areolata

netted chain fern

Herbaceous

BSW

Woodwardia virginica

Virginia chain fern

Herbaceous

BSW

Note: Meadow seeding applicable to this planting zone will include additional species ** “boulevard” indicates planting in larger areas along streets (generally 10 ft wide min., not in paving)

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:375


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O : 376

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

young Woodland For new woodlands without existing woody plants

Botanical Name

Common Name

Type

Reference Plant Community

Acer negundo

boxelder

Canopy Tree

[early succesion]

Acer rubrum

red maple

Canopy Tree

BMO, GSB

Acer saccharinum

silver maple

Canopy Tree

GSB

Carya cordiformis

bitternut hickory

Canopy Tree

GSB

Carya glabra

pignut hickory

Canopy Tree

BMO

Carya ovata

shagbark hickory

Canopy Tree

BMO, GWM

Carya ovata

shagbark hickory

Canopy Tree

BMO, GWM

Celtis laevigata

sugarberry

Canopy tree

GSB

Celtis occidentalis

common hackberry

Canopy Tree

GSB

Chamaecyparis t​ hyoides

Atlantic white cedar

Evergreen Tree

GSB

Liquidambar styraciflua

sweetgum

Canopy Tree

BMO

Liriodendron tulipifera

tulip poplar

Canopy Tree

BMO, GSB

Nyssa sylvatica

blackgum

Canopy Tree

BCO, BMO, GSB

Pinus strobus

white pine

Evergreen Tree

BMO, GWM

Pinus taeda

loblolly pine

Evergreen Tree

BMO, GSB, GWM

Platanus occidentalis

American sycamore

Canopy Tree

GSB, GWM

Populus tremuloides

quaking aspen

Canopy Tree

[early succession]

Prunus serotina

black cherry

Canopy Tree

[early succession]

Quercus alba

white oak

Canopy Tree

BMO, GSB, BCO, GWM

Quercus bicolor

swamp white oak

Canopy Tree

GSB

Quercus coccinea

scarlet oak

Canopy Tree

BCO, BMO

Quercus falcata

southern red oak

Canopy tree

BCO, BMO, GSB

Quercus laurifolia

laurel oak

Canopy Tree

GSB

Quercus lyrata

overcup oak

Canopy Tree

GSB

Quercus michauxii

swamp chestnut oak

Canopy Tree

GSB

Quercus nigra

water oak

Canopy tree

BCO, BMO

Quercus pagoda

cherrybark oak

Canopy Tree

GSB

Quercus phellos

willow oak

Canopy Tree

GSB

Quercus prinus

chestnut oak

Canopy Tree

BCO, GSB

Quercus rubra

northern red oak

Canopy Tree

BMO, GSB

Tilia americana

American basswood

Canopy Tree

GSB

CANOPY & EVERGREEN TREES

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:377


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Reference Plant Community

Amelanchier arborea

common serviceberry

Und. Tree / Shrub

BCO, BMO, GSB, GWM

Cercis canadensis

eastern redbud

Understory Tree

BMO, GSB, GWM

Chionanthus virginicus

fringetree

Understory Tree

GWM

Cornus florida

dogwood

Understory Tree

BMO, GSB

Ilex opaca

American holly cultivar

Understory Tree

BCO, BMO, GSB

Juniperus virginiana

eastern redcedar

Understory Tree

BMO, GSB, GWM

Magnolia virginiana

sweetbay magnolia

Understory Tree

BMO, GSB, GWM

Oxydendreum arboreum

sourwood

Understory Tree

BMO, OBF, GSB

Prunus virginiana

chokecherry

Understory Tree

BMO

Sassafras albidium

sassafras

Understory Tree

BCO, GSB, BMO, GWM

Aesculus flava

yellow buckeye

Und./Sh. Tree

GSB

Aesculus sylvatica

painted buckeye

Shrub

GSB

Asimina triloba

pawpaw

Shrub

GSB

Ceonanthus americanus

New Jersey tea

Shrub

BCO, GWM

Cephalanthus occidentalis

buttonbush

Shrub

GWM

Clethra alnifolia

summersweet

Shrub

GSB

Corylus americana

American hazelnut

Shrub

GSB

Ilex decidua

possumhaw

Shrub

GSB

Lindera benzoin

spicebush

Shrub

GSB

Rhus glabra

smooth sumac

Shrub

GWM

Rosa carolina

Carolina rose

Shrub

GWM

Vaccinium corymbosum

lowbush blueberry

Shrub

BMO, GSB

Vaccinium pallidum

early lowbush blueberry

Shrub

BMO, GSB

Viburnum acerifolium

mapleleaf viburnum

Shrub

BMO, GSB

Viburnum dentatum

arrowwood viburnum

Shrub

BMO, GSB

Viburnum prunifolium

blackhaw

Shrub

BMO, GSB

Andropogon virginicus

broomsedge

Herbaceous

Asclepias tuberosa

butterfly milkweed

Herbaceous

GSB, OBG

Aster azureus (Symphyotrichum oolentangiense)

skyblue aster

Herbaceous

GWM

UNDERSTORY TREES

SHRUBS

HERBACEOUS

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:378

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Reference Plant Community

Aster azureus (Symphyotrichum oolentangiense)

skyblue aster

Herbaceous

GWM

Aster ericoides (Symphyotrichum ericoides)

white heath aster

Herbaceous

BCO, GWM

Aster ericoides (Symphyotrichum ericoides)

white heath aster

Herbaceous

BCO, GWM

Campanula rotundifolia

bluebell bellflower

Herbaceous

GWM

Carex scoparia

broom sedge

Herbaceous

Chrysogonum virginianum

green and gold

Herbaceous

GSB

Chrysogonum virginianum var. virginianum

green and gold

Herbaceous

BMO

Coreopsis verticillata

threadleaf coreopsis

Herbaceous

BMO, GSB, GWM

Elymus virginicus

Virginia wildrye

Herbaceous

Eragrostis spectabilis

purple lovegrass

Herbaceous

Eupatorium hyssopifolium

hyssopleaf thoroughwort

Herbaceous

Juncus tenuis

path rush

Herbaceous

Liatris spicata

dense blazing star

Herbaceous

GWM

Onoclea sensibilis

sensitive fern

Herbaceous

BCO, GSB

Panicum virgatum

switchgrass

Herbaceous

GSB

Panicum virgatum cultivar

switchgrass (cultivar)

Herbaceous

GSB/hort

Penstemon digitalis

penstemon

Herbaceous

GSB

Phlox pilosa

downy phlox

Herbaceous

GSB, GWM

Pteridium aquilinum var.latiusculum

western brackenfern

Herbaceous

BCO

Rudbeckia hirta

blackeyed Susan

Herbaceous

BCO, GSB, GWM

Silene virginica

firepink

Herbaceous

BCO

Solidago nemoralis

gray goldenrod

Herbaceous

BCO

Solidago rugosa

wrinkleleaf goldenrod

Herbaceous

GSB

Sporobolus heterolepis

prairie dropseed

Herbaceous

GWM

Tridens flavus

purpletop

Herbaceous

Note: Meadow seeding applicable to this planting zone will include additional species

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:379


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED

O:380

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Meadow Botanical Name

Common Name

Type

Reference Plant Community

Andropogon virginicus

broomsedge

Herbaceous

[native, for visual interest/cover]

Asclepias tuberosa

butterfly milkweed

Herbaceous

GSB, OBG

Aster azureus (Symphyotrichum oolentangiense)

skyblue aster

Herbaceous

GWM

Aster ericoides (Symphyotrichum ericoides)

white heath aster

Herbaceous

BCO, GWM

Campanula rotundifolia

bluebell bellflower

Herbaceous

GWM

Carex scoparia

broom sedge

Coreopsis verticillata

threadleaf coreopsis

Herbaceous

BMO, GSB, GWM

Dichanthelium clandestinum

deertongue

Herbaceous

[cool season native grass for cover]

Elymus virginicus

Virginia wildrye

Herbaceous

[cool season native grass for cover]

Eragrostis spectabilis

purple lovegrass

Herbaceous

[native, for visual interest/cover]

Eupatorium hyssopifolium

hyssopleaf thoroughwort

Herbaceous

[native, for visual interest/cover]

Festuca rubra

Red fescue

Herbaceous

[cool season native grass for cover]

Geum triflorum

prairie smoke

Herbaceous

GWM

Juncus tenuis

path rush

Herbaceous

[native, for visual interest/cover]

Liatris spicata

dense blazing star

Herbaceous

GWM

Monarda didyma

scarlet beebalm

Phlox pilosa

downy phlox

Herbaceous

GSB, GWM

Phlox subulata

moss phlox

Herbaceous

GWM

Rudbeckia hirta

blackeyed Susan

Herbaceous

BCO, GSB, GWM

Solidago nemoralis

gray goldenrod

Herbaceous

BCO

Solidago rugosa

wrinkleleaf goldenrod

Herbaceous

GSB

Sporobolus heterolepis

prairie dropseed

Herbaceous

GWM

Tridens flavus

purpletop

Herbaceous

[native, for visual interest/cover]

Viola pedata

birdfoot violet

Herbaceous

GWM

Viola sororia

common blue violet

Herbaceous

[native, for visual interest/cover]

Zizia aurea

golden alexanders

Herbaceous

BMO, GSB

HERBACEOUS

[native, for visual interest/cover]

[native, for visual interest/cover]

REFERENCE PLANT COMMUNITY KEY: BCO American Beech, Chestnut Oak Forest BEP Box Elder, Poplar Forest BMO American Beech, Mixed Oak Forest (Red and White Oak) BSW - Blackgum, Sweetbay Wetland Forest/ Woodland GSB - Green Ash - American Sycamore, Box Elder Forest GWM - Grass or Grass and Wildflower Meadow SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:381


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Ornamental Landscape Refer to the LPP for primary direction regarding the ornamental landscape Botanical Name

Common Name

Type

Abies fraseri

fraser fir

Evergreen tree

Abies nordmanniana

nordmann fir

Evergreen tree

Abies species

fir species

Evergreen tree

Acer cappadocicum

cappadocian maple

Canopy tree

Acer negundo

box elder

Canopy tree

Acer platanoides

Norway maple

Canopy tree

Acer rubrum

red maple

Canopy tree

Acer saccharinum

silver maple

Canopy tree

Acer saccharum

sugar maple

Canopy tree

Acer species

maple species*

Canopy tree

Acer truncatum

purpleblow maple

Canopy tree

Aesculus carnea

red horsechestnut

Canopy tree

Aesculus flava

yellow buckeye

Canopy tree

Aesculus glabra

Ohio buckeye

Canopy tree

Aesculus hippocastanum

common horsechestnut*

Canopy tree

Aesculus hippocastanum ‘baumanii’

Baumann’s horsechestnut*

Canopy tree

Aesculus species

chestnut species*

Canopy tree

Asimina triloba

paw paw

Canopy tree

Betula alleghaniensis

yellow birch

Canopy tree

Betula papyrifera

paper birch

Canopy tree

Carya cordiformis

bitternut hickory

Canopy tree

Carya glabra

pignut hickory

Canopy tree

Carya ovata

shagbark hickory

Canopy tree

Carya species

hickory species

Canopy tree

Cedrus atlantica

blue atlas cedar

Evergreen tree

Cedrus deodara

ceodar cedar

Evergreen tree

Cedrus species

cedar species

Evergreen tree

Celtis occidentalis

common hackberry

Canopy tree

Chamaecyparis nootkatensis

Alaska-cedar

Evergreen tree

Chamaecyparis obtusa ‘crippsii’

hinoki falsecypress

Evergreen tree

Chamaecyparis pisifera

Japanese falsecypress

Evergreen tree

Cladastrus kentuckea

yellowwood

Canopy tree

Cryptomeria japonica

Japanese cryptomeria

Evergreen tree

Cunninghamia lanceolata

common Chinafir

Evergreen tree

Diospyros virginiana

common persimmon

Canopy tree

Fagus grandifolia

American beech

Canopy tree

Fagus species

beech species

Canopy tree

CANOPY & EVERGREEN TREES

SENSITIVE BUT UNCLASSIFIED

O:382

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Fagus sylvatica

European beech

Canopy tree

Fagus sylvatica ‘asplenifolia’

cut leaf European beech

Canopy tree

Fraxinus americana

white ash

Canopy tree

Fraxinus pennsylvanica

green ash

Canopy tree

Fraxinus species

ash species

Canopy tree

Ginkgo biloba

ginkgo

Canopy tree

Gleditisia triacanthos var. inermis

thornless honeylocust

Canopy tree

Gleditsia triacanthos

honeylocust

Canopy tree

Gymnocladus dioicus

Kentucky coffee-tree

Canopy tree

Ilex cornuta

Chinese holly

Evergreen tree or shrub

Ilex opaca

American holly tree

Evergreen tree

Ilex species

holly species*

Evergreen tree

Juglans nigra

black walnut

Canopy tree

Juglans regia

English walnut

Canopy tree

Juglans species

walnut species

Canopy tree

Juniperus virginiana

eastern red-cedar

Evergreen tree

Larix kaempferi

Japanese larch

Canopy tree

Larix leptolepis

Japanese larch

Canopy tree

Liquidambar styraciflua

sweet gum

Canopy tree

Liriodendron tulipifera

tulip poplar

Canopy tree

Maclura pomifera

osage orange*

Canopy tree

Magnolia grandiflora

southern magnolia

Broadleaf ev. tree

Metasequoia glyptostroboides

dawn redwood

Canopy tree

Morus rubra

Red mulberry

Canopy tree

Nyssa sylvatica

Black tupelo

Canopy tree

Picea abies

Norway spruce

Evergreen tree

Picea orientalis?

Oriental Spruce

Evergreen tree

Picea pungens

Colorado spruce

Evergreen tree

Pinus nigra

Austrian pine

Evergreen tree

Pinus ponderosa

Ponderosa pine

Evergreen tree

Pinus species

pine species

Evergreen tree

Pinus strobus

Eastern white pine

Evergreen tree

Pinus taeda

Loblolly Pine

Evergreen tree

Platanus occidentalis

American sycamore

Canopy tree

Platanus species

sycamore species

Canopy tree

Populus deltoides

eastern cottonwood

Canopy tree

Prunus caroliniana

Carolina cherrylaurel

Evergreen tree

Prunus serotina

black cherry

Canopy tree

Prunus species

cherry species*

Canopy tree

Quercus acutissima

sawtooth oak*

Canopy tree

Quercus alba

white oak

Canopy tree

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:383


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Quercus bicolor

swamp white oak

Canopy tree

Quercus coccinea

scarlet oak

Canopy tree

Quercus macrocarpa

bur oak

Canopy tree

Quercus marilandica

blackjack oak

Canopy tree

Quercus palustris

pin oak

Canopy tree

Quercus phellos

willow oak

Canopy tree

Quercus prinus

chestnut oak

Canopy tree

Quercus robur

English oak

Canopy tree

Quercus rubra

red oak

Canopy tree

Quercus species

oak species

Canopy tree

Quercus stellata

post oak

Canopy tree

Quercus velutina

black oak

Canopy tree

Robinia pseudoacacia

black locust

Canopy tree

Robinia species

locust species

Canopy tree

Salix “Niobe�

niobe willow

Canopy tree

Salix babylonica

weeping willow

Canopy tree

Salix x sepulcralis

weeping willow

Canopy tree

Sassafras albidum

sassafras

Canopy tree

Sequoiadendron gigantea

giant sequoia

Evergreen tree

Styphnolobium japonicum

Japanese pagodatree

Canopy tree

Taxodium ascendens

pondcypress

Canopy tree

Taxodium distichum

bald cypress

Canopy tree

Thuja occidentalis

eastern arborvitae

Evergreen tree

Thuja orientalis

oriental arborvitae

Evergreen tree

Tilia americana

American linden

Canopy tree

Tilia cordata

small leaved linden

Ornamental tree

Tilia x europaea

european linden

Canopy tree

Torreya nucifera

Japanese torreya

Evergreen tree

Tsuga canadensis

Canadian hemlock

Evergreen tree

Tsuga species

hemlock species

Evergreen tree

Ulmus americana

American elm

Canopy tree

Ulmus parvifolia

Chinese elm

Canopy tree

Ulmus procera

English elm

Canopy tree

Ulmus rubra

slippery elm

Canopy tree

Ulmus species

elm species

Canopy tree

Zelkova serrata

Japanese zelkova

Canopy tree

Acer palmatum

Japanese maple*

Ornamental tree

Amelanchier species

serviceberry species

Ornamental tree

Carpinus caroliniana

American hornbeam

Ornamental tree

Castanea mollissima

Chinese chestnut

Ornamental tree

UNDERSTORY TREES

SENSITIVE BUT UNCLASSIFIED

O:384

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Cercis canadensis

eastern redbud

Ornamental tree

Cornus florida

flowering dogwood

Ornamental tree

Crataegus phaenopyrum

Washington hawthorne

Ornamental tree

Franklinia alatamaha

franklinia

Ornamental tree

Koelreuteria bipinnata

Chinese flametree

Ornamental tree

Koelreuteria paniculata

golden raintree*

Ornamental tree

Magnolia acuminata

cucumbertree

Ornamental tree

Magnolia soulangiana

saucer magnolia

Ornamental tree

Magnolia stellata

star magnolia

Ornamental tree

Magnolia virginiana

sweetbay magnolia

Ornamental tree

Malus species

ornamental crabapple

Ornamental tree

Morus alba ‘chapparal’

Weeping mulberry

Ornamental tree

Prunus avium

sweet cherry*

Ornamental tree

Prunus serrulata ‘Kwanzan’

kwanzan cherry

Ornamental tree

Prunus serrullata

Japanese cherry

Ornamental tree

Prunus subhirtella var. pendula

weeping cherry

Ornamental tree

Prunus x yedoensis

yoshino cherry

Ornamental tree

Pyrus communis

common pear

Ornamental tree

Stewartia malacodendron

silky stewartia

Ornamental tree

Stewartia pseudocamellia

Japanese stewartia

Ornamental tree

Styrax species

snowbell species

Ornamental tree

Viburnum prunifolium

blackhaw viburnum

Ornamental tree/ shrub

Berberis julianae

wintergreen barberry

Evergreen shrub

Buxus sempervirens

common boxwood

Evergreen shrub

Camellia japonica

Japanese camellia

Evergreen shrub

Chaenomeles speciosa

common flowering quince

Canopy shrub

Cupressus species

cypress species

Evergreen shrub

Deutzia scabra

fuzzy deutzia

Canopy shrub

Euonymous americanus

American euonymus

Canopy shrub

Exochorda racemosa

common pearlbush

Canopy shrub

Ilex aquifolium ‘variegata’

variegated English holly

Evergreen shrub

Ilex cornuta ‘Burfordii’

burford holly

Evergreen shrub

Ilex crenata

Japanese holly

Evergreen shrub

Ilex species

holly species*

Evergreen shrub

Juniperus chinensis

Chinese juniper

Evergreen shrub

Lagerstroemia indica

crape myrtle

Canopy shrub

SHRUBS AND VINES

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:385


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

Botanical Name

Common Name

Type

Lonicera sempervirens

Trumpet honeysuckle

Semi-evergreen vine

Lonicera tatarica

tartarian honeysuckle

Canopy shrub

Osmanthus heterophyllus

Holly osmanthus

Evergreen shrub

Philadelphus species

Mockorange species*

Canopy shrub

Phyllostachys species

Bamboo species*

Evergreen plant

Poncirus trifoliata

hardy orange*

Canopy shrub

Prunus laurocerasus

cherry laurel

Evergreen shrub

Rubus species

bramble species*

Canopy shrub

Salix species

willow species

Dediduous tree

Smilax tamnoides

bristly greenbriar

Canopy vine

Spiraea alba

meadowsweet

Canopy shrub

Spiraea thunbergii

thunberg spirea

Canopy shrub

Syringa vulgaris

common lilac

Canopy shrub

Taxus x media

Anglojap yew

Evergreen shrub

Toxicodendron radicans

poison ivy

Canopy vine

Trachelospernum jasminoides

confederate jasmine

Evergreen vine

Viburnum plicatum var.tomentosum

doublefile viburnum*

Canopy shrub

Vitex agnus-castus

chastetree

Canopy shrub

Vitis species

grape species*

Canopy vine

Wisteria floribunda

Japanese wisteria*

Ornamental vine

Wisteria species

Wisteria species*

Ornamental vine

Yucca species

yucca species

Evergreen shrub

*do not plant non-native invasive species: see invasiveplantsatlas. org

SENSITIVE BUT UNCLASSIFIED

O:386

andropogon associates ltd.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

SENSITIVE BUT UNCLASSIFIED andropogon associates ltd.

O:387


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix O: Plant Species List for Native Plant Community Structures

This page intentionally left blank.

SENSITIVE BUT UNCLASSIFIED

O:388

andropogon associates ltd.


Appendix P

Site Lighting Master Plan

Please see the attached DVD for this publication.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix P: Site Lighting Master Plan

This page intentionally left blank.

SENSITIVE BUT UNCLASSIFIED

P:390

andropogon associates ltd.


Appendix Q

Hydrogeological Investigation Findings

Detail by GeoConcepts

Please see the attached CD for this publication.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix Q: Hydrogeological Investigation Findings

This page intentionally left blank.

SENSITIVE BUT UNCLASSIFIED

Q:392

andropogon associates ltd.


Appendix R

Stormwater Modeling, Analysis & Results

Please see the attached CD for this publication.


S t . E l i z a b e t h s We s t C a m p u s - L a n d s c a p e I n t e g r a t i o n P l a n Appendix R: Stormwater Modeling, Analysis & Results

This page intentionally left blank.

SENSITIVE BUT UNCLASSIFIED

R:394

andropogon associates ltd.


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