Salton Sea Salinity Gradient Solar Pond Pilot Project Initial Study

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timothy krantz environ mental consulting

INITIAL STUDY AND ENVIRONMENTAL CHECKLIST SALTON SEA SALINITY GRADIENT SOLAR POND PILOT PROJECT SALTON SEA, IMPERIAL COUNTY, CALIFORNIA

Prepared for: Imperial Irrigation District 333 East Barioni Boulevard Imperial, California 92251-0936

Prepared by: Timothy Krantz Environmental Consulting 39611 Oak Glen Road, #11 Yucaipa, CA 92399 (909) 705-6707

May, 2016

1.1 ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED The environmental factors checked below would be potentially affected by the proposed project, involving at least one impact that is a “Potentially Significant Impact” as indicated by the checklist. Aesthetics Biological Resources Greenhouse Gas Emissions Land Use & Planning Population/Housing Transportation & Traffic

Agriculture & Forestry Resources Cultural Resources Hazards & Hazardous Materials

Air Quality Geology/Soils Hydrology & Water Quality Noise Recreation Mandatory Findings of Significance

Mineral Resources Public Services Utilities & Service Systems

1.2 DETERMINATION On the basis of this initial evaluation: I find that the proposed project COULD NOT have a significant effect on the environment, and a NEGATIVE DECLARATION will be prepared. I find that although the Proposed project could have a significant effect on the environment, there will not be a significant effect in this case because revisions in the project have been made by or agreed to by the project proponent. A MITIGATED NEGATIVE DECLARATION will be prepared. I find that the proposed project MAY have a significant effect on the environment, and an ENVIRONMENTAL IMPACT REPORT is required. I find that the proposed project MAY have a “potentially significant impact” or “potentially significant unless mitigated” impact on the environment, but at least one effect 1) has been adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has been addressed by mitigation measures based on the earlier analysis as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the effects that remain to be addressed. I find that although the proposed project could have a significant effect on the environment, because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards and (b) have been avoided or mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or mitigation measures that are imposed upon the proposed project, nothing further is required. Signature Imperial Irrigation District

Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea, CA

Date

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Project Description

Figure 6. Conceptual View of Project showing adjacent Âź acre ponds

The small scale 1/4 acre version of this Project will develop a process for reclamation of hyper-saline water from the Salton Sea to sustain a Âź acre marine habitat pond on recently exposed lakebed. The Project will construct a Âź acre salinity gradient solar pond adjacent to the habitat pond to receive saturated brine derived from the Salton Seawater distillation and habitat pond water recycling as illustrated in Figure 6. There will be no power generation from the solar pond, just heat for seawater distillation. Evaporators and a condenser from an existing VTE distillation pilot plant will be installed at the ponds to maintain a salinity gradient that will trap heat from the sun to drive a long term on site thermal distillation process. The pond site distillation plant will maintain both the marine habitat pond and the salinity gradient solar pond with distilled water make-up. Evaporative losses will be controlled to the extent practicable with a floating film or non-toxic molecular monolayer and made up from distilled Salton Seawater. On completion of new environmental and construction permitting expected in late 2016 and early 2017, the two ponds will be built. The habitat pond can be in operation within 6 months of construction start. The VTE Demonstration Plant now in the final stages of construction will distill Salton Sea water with heat from low pressure geothermal steam to dilute the habitat pond to a target salinity of 35,000 ppm TDS or less with no accumulation of selenium or other critical contaminants.

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Figure 7. Dilute Marine Habitat Pond with Distillate while Filling Solar Pond with Brine

The Phase 1 process of diluting the habitat pond with distilled Salton Sea water while filling the solar pond with brine is illustrated in Figure 7.

Figure 8. Maintain Marine Habitat Pond with Distillate while Filling Solar Pond with Brine

In the Phase 2 process illustrated in Figure 8, the VTE Demo Plant will sustain the marine habitat pond with distillate while the salinity gradient solar pond continues to be filled with brine. The VTE Demonstration Plant will need about two and a half months of continuous operation to fill the solar pond with enough saturated Salton Sea brine to have about three foot depth of lower convective zone and be able to create a three foot deep salinity gradient layer above it by blending in distilled water from the VTE Demonstration Plant with saturated brine in the solar pond. Alternatively, the VTE Demonstration Plant can make brine at a variable salinity dependent on the solar pond depth and deliver it to the top of the forming gradient layer. The alternative method would be more efficient, but could allow premature solar heating of the convective layer below that could damage the gradient.

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Figure 9. Maintain Marine Habitat and Solar Pond with Energy from Solar Pond

The salinity gradient solar pond and integrated distillation plant can be in operation about 1 ½ years after construction start when the solar pond has a gradient established so that it can capture solar energy to drive the distillation plant at the ponds. The operational Phase 3 process is illustrated in Figure 9. The owner of the existing Salton Sea desalination plant, Sephton Water Technology, Inc. has pledged to donate the use of the plant equipment it owns for the three year or longer term of the project. The desalination plant will be relocated to the solar pond under this Project. The assembly of the existing Salton Sea desalination plant at its current installation at the nearby CalEnergy Operating Company geothermal power plant was previously funded by $672,233 in grants from the U.S. Bureau of Reclamation. Expansion of the plant, now underway, has been funded by a $1.3 million grant from the California Department of Water Resources plus $150,000 from the U.S. Bureau of Reclamation with additional Reclamation funding being contracted.

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No Impact

Impact

Less Than Significant Impact After Mitigation Incorporated Than Significant Less

Potentially Significant Impact

Environmental Checklist

1. AESTHETICS. Would the project: a. Have a substantial adverse effect on a scenic vista? X b. Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic X highway? c. Substantially degrade the existing visual character or quality of the site and its surroundings? X d. Create a new source of substantial light or glare that would X adversely affect day or nighttime views in the area? e. Create a new source of substantial shade or shadow that would X adversely affect daytime views in the area? The primary objectives of the Project are three-fold: 1) demonstrate the technical feasibility of the salinity-gradient solar pond to produce energy; 2) create and maintain marine wildlife habitat ponds around the exposed shoreline of the Sea; and 3) cover the playa area with ponds and decrease particulate matter from becoming airborne during wind events as part of an integrated dust management program for the Sea. The second and third Project objectives will both result in beneficial effects on aesthetics in the area. No significant adverse impacts will occur with regard to aesthetic resources. a) Due to the isolated nature of this project, no scenic vistas will be affected. No impact. b) The Project will not substantially damage scenic resources. One objective of the proposed project is to restore scenic resources that have been degraded due to the receding Salton Sea shoreline, exposing the playa and eliminating shallowwater habitat. The changes in the visual character of the site during construction would not be considered significant because of the isolated nature of this area, as well as the lack of any significant visual resources within the project boundary. The project will therefore have a beneficial effect on scenic resources. No impact. c) The Project will change the existing visual character or quality of the site and its surroundings. The habitat pond will provide for the reestablishment of scenic values that are associated with shallowwater shorebird habitat, and therefore will have a beneficial effect on the visual character of the area. Due to the isolated nature of the project site, the Vertical Tube Evaporators (VTE) and other equipment coinciding with the solar pond will not have a significant impact on the visual quality of this area. No impact. d) The Project will not create a new source of substantial light or glare that would adversely affect day or nighttime views in the area. The proposed project lies adjacent to Lack and Lindsey roads, proximal to the existing geothermal plant, and out of range of any sensitive viewshed. No impact. e) The project will not create a new source of substantial shade or shadow that would adversely affect daytime views in the area. No impact. Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea, CA

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

2. AGRICULTURE AND FORESTRY RESOURCES. In order to determine whether impacts to agricultural resources are significant, the Lead Agencies may refer to the California Agricultural Land Evaluation and Site Assessment (LESA) Model (1997) prepared by the California Department of Conservation as an optional model to use in assessing impacts on agriculture and farmland. Would the project: a. Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? b. Conflict with existing zoning for agricultural use, or a Williamson act contract? c. Conflict with existing zoning for, or cause rezoning of, forest land, timberland, or timberland zoned timberland production? d. Result in the loss of forest land or conversion of forest land to nonforest use? e. Involve other changes in the existing environment that, due to their location or nature, could result in conversion of Farmland, to non-agricultural use?

X

X X X X

a) The Project will not convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use. No impact. b) The Project will not conflict with existing zoning for agricultural use, or a Williamson Act contract. The proposed project site is a shallow saline playa that has never supported agricultural land use. No impact. c) The Project will not conflict with existing zoning for, or require rezoning of forest land, timberland, or land zoned for timber production. The proposed site is a treeless playa that has historically been filled by the Salton Sea. No impact. d) The Project will not result in the loss of forest land or conversion of forest land to non-forest use, as the existing site is a treeless playa. No impact. e) The Project will not result in conversion of existing farmland to non-agricultural use. Furthermore, the proposed project will provide some modest mitigation that will decrease dust emission from the site and deposition of particulate matter on nearby agricultural lands. No impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

3. AIR QUALITY. Where available, the significance criteria established by the applicable air quality management or air pollution control district may be relied upon to make the following determinations. Would the project: a. Conflict with or obstruct implementation of the applicable air X quality plan or clean air programs? b. Violate any air quality standard or contribute substantially to an existing or projected air quality violation? X c. Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including X releasing emissions, which exceed quantitative thresholds for ozone precursors)? d. Expose sensitive receptors to substantial pollutant X concentrations? e. Create objectionable odors affecting a substantial number of people? X The Project is within the Salton Sea Air Basin (SSAB), the southern portion of which is managed by the Imperial County Air Pollution Control District (ICAPCD). Imperial County is designated as being in compliance with National Ambient Air Quality Standards (NAAQS) for CO, NO2, and sulfur dioxide (SO2). However, Imperial County is designated as a State nonattainment area for the 1-hour O3, PM10, and PM2.5 California Ambient Air Quality Standards (CAAQS). In April 2012, the USEPA issued its final designations, which are based on air quality monitoring data, recommendations submitted by the states and tribes, and other technical information. Imperial County and the portion of Riverside County within the SSAB were designated as nonattainment areas, as these areas currently exceed the 2008 ozone standards. The area designations and classifications are effective July 20, 2012. SSAB is currently designated as a nonattainment area for the 8-hour NAAQS for ozone, PM10, and PM2.5. The project area is in attainment with the other applicable criteria pollutants. In 2009, ICAPCD issued the “Final 2009 Imperial County State Implementation Plan for Particulate Matter Less Than 10 Microns in Aerodynamic Diameter”. This document provides an overview of ICAPCD’s PM10 control program and describes fugitive dust rules and analyses of control effectiveness. It also addresses the anticipated future impact of PM10 emissions from the receding Salton Sea on Imperial County air quality (ICAPCD 2009).

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As described in the 2009 State Implementation Plan (SIP) and the Imperial Irrigation District (IID) Air Quality Mitigation Program, as the Salton Sea recedes, exposed playa will be a potential source of PM10 emissions. The proposed project will be located on exposed playa and will provide pro-active dust control of emissions from this area. This will represent a beneficial impact on air quality. The main air quality impact would be during construction. Diesel trucks and construction equipment will emit exhaust while doing the berm earthwork. There would be some construction dust that gets past mitigation measures such as wetting the earthworks. There will be some commuting traffic from work crews on the order of a dozen people. There will be some welding and mechanical work to reinstall one existing distillation plant at the solar pond. Construction impacts on air quality are anticipated to be less than significant During operation the only air quality impact would be electrical energy used by pumps and purchased from IID. The maximum draw would be about 100kW. While the direct project energy uses are geothermal or solar, IID is mostly on fossil fuels so the GHG equivalent of the electrical energy bought from IID would also have to be estimated. Appendix C of the Initial Study and Environmental Assessment provide estimated calculations of emissions related to construction activities. Table 1 Attainment Status for the Imperial County Area

Pollutant

Federal Status

Calexico

Carbon Monoxide (CO)

Unclassified/attainment

Attainment

All other areas

Carbon Monoxide (CO)

All areas

Ozone (O3 ) (1-hour)

Unclassified/attainment No longer subject to 1-hour Federal standard

Attainment Nonattainment (moderate)

All areas

Ozone (O3) (8-hour)

Nonattainment (marginal)

Nonattainment

All areas

PM10

Nonattainment (serious)

Nonattainment

PM2.5

Nonattainment

Nonattainment

All other areas

PM2.5

Unclassified/attainment

Unclassified

All areas

Nitrogen dioxide (NO2)

Unclassified/attainment

Attainment

All areas

Sulfur dioxide (SO2)

Attainment

Attainment

Calexico

CA Status

a) USEPA often only declares Nonattainment Areas; everywhere else is listed as e i t h e r Unclassifiable/Attainment or Unclassifiable.

b) A design value below the NAAQS for data through the full year or smog season prior to the attainment date is typically required for attainment demonstration.

c) 1997 8-hour O3 standard (0.08 ppm) was reduced (0.075 ppm), effective May 27, 2008; the 1997 O3 standard and most related implementation rules remain in place until the 1997 standard is revoked by USEPA.

d) New NO2 1-hour standard, effective August 2, 2010; attainment designations January 20, 2012; annual NO2 standard retained. e) The 1971 Annual and 24-hour SO2 standards were revoked, effective August 23, 2010; however, these 1971 standards will remain in effect until one year after EPA promulgates area designations for the 2010 SO2 1-hour standard. Area designations expected in 2012 with SSAB designated Unclassifiable/Attainment.

f) Annual PM10 standard was revoked, effective December 18, 2006; re-designation request to Attainment of the 24- hour PM10 standard is pending with USEPA. Source: ARB 2011a, ARB 2011b, USEPA 2012c

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Table 2 Ambient Air Quality Summary – Imperial County (2009-2011) Pollutant Standards Carbon Monoxide (CO) National maximum 8-hour concentration (ppm) State maximum 8-hour concentration (ppm) State maximum 1-hour concentration (ppm) Number of Days Standard Exceeded NAAQS 8-hour (>9.0 ppm) CAAQS 8-hour (>9.0 ppm) CAAQS 1-hour (>20.0 ppm) Nitrogen Dioxide (NO2) State maximum 1-hour concentration (ppm) Annual Average (ppm) Number of Days Standard Exceeded CAAQS 1-hour Ozone State max 1-hour concentration (ppm) National maximum 8-hour concentration (ppm) Number of Days Standard Exceeded CAAQS 1-hour (>0.09 ppm) CAAQS 8- hour (>0.070 ppm)/NAAQS 8-hour (>0.075 ppm) Particulate Matter (PM10) a National maximum 24-hour concentration (µg/m3) State maximum 24-hour concentration (µg/m3) State annual average concentration (µg/m3) Estimated Number of Days Standard Exceeded NAAQS 24-hour (>150 µg/m3) CAAQS 24-hour (>50 µg/m3) Particulate Matter (PM2.5) a National maximum 24-hour concentration (µg/m3) State maximum 24-hour concentration (µg/m3) National annual average concentration (µg/m3) State annual average concentration (µg/m3) Estimated Number of Days Standard Exceeded NAAQS 24-hour (>35 µg/m3)

2009

2010

2011

NA 2.6 5.0

NA 3.7 17.4

NA 7.5 25.1

0 0 0

0 0 0

0 0 0

0.107 0.008 0 0.015 0.087 9

0.141 0.004 0 0.122 0.082 3

0.117 0.009 0 0.103 0.084 5

30/11

29/10

21/12

NA 192 47.9

NA 113 33.6

NA 269 40.9

6.1 104.6

0 47.9

6.6 93.4

45.0 100.9 8.0 18.7

50.9 54.0 12.9 12.7

80.3 103.5 7.5 7.5

NA

NA

NA

Source: ARB 2012 2222012201222201320 13

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a) The Project will not violate any air quality standard or contribute substantially to an existing or projected air quality violation. The project will not conflict with or obstruct implementation of applicable air quality management plans. Less than significant impact. b) In order to reduce adverse impacts resulting from construction, all activities shall comply with applicable ICAPCD Regulation VIII rules to ensure that measures to control dust and particulates, including diesel particulate emissions, are implemented. In 2007, ICAPCD published guidelines for CEQA compliance and recommended threshold criteria for determining the significance of impacts on air quality from construction and operational activities. Construction-related emissions may exceed the recommended levels of significance for NOX for the Proposed Action. However, such constructionrelated emissions will be managed through the regulatory oversight of the ICAPCD via reporting mechanisms established by federal, state, and local laws. All other construction impacts on air quality are anticipated to be less than significant. Less than significant impact. c) The Project is not anticipated to generate new vehicle trips and is not anticipated to generate any additional activities related to maintenance or operations that would increase from existing levels. Thus, the proposed project will not result in a cumulatively considerable net increase of any criteria pollutant for which the project region is in non-attainment under an applicable federal or state ambient air quality standard, including releasing emissions that exceed quantitative thresholds for ozone precursors. Operational impacts on air quality shall be less than significant. Less than significant impact. d) The Project will not expose sensitive receptors to substantial pollutant concentrations as the project location is not located near schools, hospitals, or any other sensitive receptor and will not create any impact to sensitive receptors. No impact. e) The Salton Sea in the project site area is characterized by malodors caused by eutrophication in the Sea. The relative contribution of short-term construction impacts to odors is less than significant. Less than significant impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 4. BIOLOGICAL RESOURCES. Would the project: a. Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Game or U.S. Fish and Wildlife Service? b. Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, and regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service? c. Have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means? d. Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites? e. Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance? f. Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?

X

X

X

X

X X

A Biological Assessment (Bishop, 2015) of the Project site has been completed and is attached to this document as APPENDIX A. The Biological Assessment characterizes the existing resources on site and in the Project vicinity. In summary, the biological assessment has determined that the proposed action may affect, but is not likely to adversely affect the endangered Desert pupfish. Mitigation measures to avoid significant impacts to the Desert Pupfish have been incorporated into the pilot study adaptive management plan. The biological assessment has also determined that the proposed action will have no effect on the endangered Yuma Ridgway’s Rail. The assessment incorporates other mitigation recommendations for tree, shoreline, and wetland habitat. A Biological Advisory Committee (BAC) has been formed with members representing the biological resource regulatory agencies, including the California Department of Fish and Wildlife (CDFW), U.S. Fish and Wildlife Service (FWS), U.S. Geological Survey Biological Resources Division (USGS), U.S. Bureau of Reclamation (USBR), the Sonny Bono Salton Sea National Wildlife Refuge (NWR), the Imperial Irrigation District and other biologists with expertise in the Salton Sea area. The BAC will develop a comprehensive adaptive management plan to make recommendations for installation, monitoring and modification of mitigation measures with regard to biological resources throughout the duration of the pilot project.

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To address interrelated effects of the Action, biological monitoring and adaptive management of various aspects will be implemented. The biological monitoring program will focus on two aspects of the ponds: restricting birds from the solar pond, while encouraging their use of the habitat pond by providing forage in the form of a healthy community of marine fish and invertebrates and possibly by providing snags and one or more nesting islands. A select team of regulatory and agency biologists and ecologists have agreed to serve as the Biological Advisory Committee (BAC) for the Project. A biological concern for this project is the potential harm to diving waterfowl on the solar thermal pond. The solar pond will range from a minimum working depth of 6 ½ feet at start up to a maximum depth after more than a year of brine storage of up to 12 feet with a layer of hot concentrated brine stored at the bottom. While close to ambient temperature on the surface, the solar thermal pond may achieve temperatures at depths of 4 ½ feet and more below the surface as high as 94ºC (201ºF) in the summer, representing a potential hazard to waterfowl that may mistake the solar pond for a natural pond, while the adjacent habitat pond is designed to be attractive to waterfowl and provide suitable habitat for the birds. Therefore, avian exclusion from the solar pond is a priority for the project. Extensive research has been conducted on avian bird control by Harris and Davis in 1998, whose work, “Evaluation of the Efficacy of Products and Techniques for Airport Bird Control,” cites over 300 academic papers on the subject. This research supports the implementation of multifaceted approaches in order to achieve maximum bird exclusion. The study found that birds tend to habituate to environmental deterrents, such as audio, visual, or pyrotechnic exclusion methods over time. The research suggests that installation of a physical barrier, such as vertical poles or netting, may be necessary in order to achieve optimal bird exclusion (ibid.). In addition to installation of physical barriers to prevent birds from landing on the solar pond, removal of attractive features for nesting, and the use of a “lure” pond (the habitat pond) are the most effective methods for avian exclusion. Any low-lying plants surrounding the solar pond shall be removed and work areas shall be covered with gravel. Contrarily, the adjacent habitat pond shall be managed to provide a sustained source of forage for fish eating and diving birds by inoculating the pond with native invertebrates and introducing one or more selected fish species. Ample food, appropriate salinity level, nesting islands, snags, and adaptive management features are intended to help to lure birds away from attempting to forage in the solar pond. A comparative example of bird exclusion is the design report for the Piñon Ridge Project in Montrose City, Colorado. This project entails an evaporation pond, in which the acidity of the water posed a potential threat to waterfowl. Similar to our project, the evaporation pond required an exclusion method which supported an evaporation pond, and therefore would only minimally inhibit sunlight from heating the water. The proposed project was 4.13 acres, and was located on the Dolores River, a tributary to the Colorado River, providing attractive suitable waterfowl habitat. A netting system was engineered to cover the entire pond, serving as a potential template for design of a similar system which could be applied to the solar pond to exclude birds. Adaptive management strategies will focus on avian exclusion from the solar pond; and on water quality and healthy aquatic and avian population maintenance at the habitat pond. One of the primary objectives of the pilot Project is to determine if one can operate a Vertical Tube Evaporator (VTE) simply with the solar energy captured in the solar pond. The VTE can then be used to distill Salton Sea water for dilution to the design salinity of the habitat pond. Thus, the habitat pond is itself sustained by the solar pond. The solar pond will develop temperatures of as much as 94ºC (201ºF) in the Lower Convection Zone, potentially harming a diving bird, such as an eared grebe or diving duck, were it to land on and dive into the solar pond. Various measures or combinations of measures may be implemented to prevent birds from landing on the solar pond. These may include: • Vertical poles extending above the surface at close intervals, making it difficult for birds to land on the surface; • Horizontal polypropylene cords or lines gridding the surface, with foil flags or other features to further dissuade birds from landing; • Removal of vegetation cover or other habitat features from the solar pond.

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Biological Monitoring Program The BAC will establish a regular schedule for biological monitoring of the solar pond and habitat pond. Biological monitoring results will be documented in monthly reports and circulated to the members of the BAC for their review and recommendations. Physical environmental monitoring shall include water chemistry, aqueous soil chemistry, as well as invertebrate and vertebrate biological monitoring programs. Mitigation Measures Desert Pupfish: To mitigate for the species through this project, installation of a fish exclusion screen with minimum mesh size of 0.25” and submersion of the seawater intake in 3ft or greater water depth off the Salton Sea shore shall be employed to prevent desert pupfish from being drawn into the sea water intake pump. The seawater intake to the desalination plants will be screened with a mesh area many times larger than the cross section of the intake pipe and an evenly distributed flow across the screen. If a self-cleaning fish screen design is feasible in the shallow water available, the screen shall be designed to have an approach velocity of less than 0.4 feet per second for the maximum seawater intake flow rate of 200 gpm. Otherwise the screen shall be manually cleaned once per day of operation and the design approach velocity will be less than 0.1 feet per second for the maximum intake flow of 200 gpm—slow enough that healthy fish may easily swim away from the pump intake. Recent Biological monitoring efforts for desert pupfish indicate that fish may move along the near-shore environment, but no fish fry were identified in water greater than three feet in depth. (Crayon, pers.comm.) Therefore, placement of the seawater intake pipe at three feet or greater depth to avoid take of fish fry, together with 0.25” mesh screening measures to avoid take of adults, shall avoid desert pupfish altogether. Tree Habitat: To avoid effects to nesting birds, trees that may be in the immediate project construction area should be removed outside of nesting season when possible. The young tamarisk thicket just to the south of the project area should be considered for removal to eliminate potential nesting adjacent to the project site during construction. If it is deemed the trees will need to be removed, they will be inspected and removed outside of the nesting season. Construction should be completed outside of the nesting season to limit disturbance by vehicle traffic and noise inundation to possible wintering or nesting birds in the remaining trees. If construction activity is necessary during the nesting season, surveys for nesting birds will be conducted prior to the activity and the activity will not commence if nesting birds are identified. The tree to the north of the habitat ponds and near the sea wall shall stay as it provides perches for Double-Crested cormorants. To the extent possible, the VTE to pond pipeline route has been designed and shall be installed so as not to disturb or cause the removal of these trees. Shoreline habitat: To mitigate effects to potential shore birds, where practical, construction will be completed outside of nesting season. If construction activity is conducted during the nesting season, bird surveys will be conducted prior to construction and resurveyed if construction stops for a month or more. If nesting species are identified within or immediately adjacent to the Project construction area, no construction activity will be allowed, unless CDFW-approved buffers can be established. Wetlands habitat: To mitigate effects to marsh birds, construction plans will exclude the identified marsh areas and minimize indirect effects as much as possible. If practical, construction will be completed outside of nesting season to limit disturbance by vehicle traffic and noise inundation. If construction activity will be conducted during the nesting season, bird surveys should be conducted prior to construction and resurveyed if construction stops for a month or more. If nesting species are identified within or immediately adjacent to the Project construction area, no construction activity will be allowed, unless CDFW-approved buffers or noise-attenuation measures can be established.

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a)

The Project would not have a substantial adverse effect, either directly or indirectly, on any species identified as a candidate, sensitive, or special status s pecies in local or regional plans, policies, or regulations, or by the CDFW or USFWS. The proposed project is a result of a well-coordinated effort between the IID, the NWR, CDFW and USFWS. Less than significant after mitigation.

b)

The Project would not have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, and regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service. A local existing Conservation plan is the NWR CCP. The project site is not included in the NWR; however it is adjacent to this area. The CCP was formed in July 2013, and encompasses a collaborative and coordinated effort between the Refuge and the CDFW and USFWS. Less than significant after mitigation.

c) The Project will not have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means. The proposed project will be constructed on playa exposed in the last several years that previously supported marine forage by several species of birds. Portions of the project area may become temporarily inundated due to surge during high winds, seasonal variations in the high water level of the Salton Sea, and changes in the outflow pattern from two nearby irrigation drains. The Salton Sea level is on an annual declining trend, so all of the project area is expected to become indefinitely exposed in the next few years. A Federal Section 404 permit and a State Section 1602 permit are being applied for. The proposed project includes saline water pumped into a constructed pond on the playa to supply fish and invertebrate forage that previously was available on the site. Project will create wetlands and recreate some of the historical biological values that were present. Less than significant after mitigation. d) The Project will not interfere substantially with the movement of any native, resident, or migratory fish or wildlife species; or with established native, resident, or migratory wildlife corridors n or will it impede the use of native wildlife nursery sites. The project will be monitored for any and all resident species. The project will have a beneficial impact on fish and wildlife species. Less than significant impact after mitigation.

No Impact

The Project will not conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan. This project is located outside of the NWR CCP boundary.

Less Than Significant Impact

f)

Less Than Significant Impact After Mitigation Incorporated

The Project will not conflict with any local policies or ordinances protecting biological resource s. Th e p roposed p roject is ou tside , but adjace nt to the plan boundaries; none theless i t is consi s t ent with the NWR CCP, Jul y 2013, which outlines plans and methodologies for maintaining and restoring habitat and species in and around the Salton Sea environs. The project is consistent with local plans and policies. Less than significant impact.

Potentially Significant Impact

e)

5. CULTURAL RESOURCES. Would the project: a. Cause a substantial adverse change in the significance of a historical resource as defined in CEQA Guidelines Section 15064.5?

X

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b. Cause a substantial adverse change in the significance of a archeological resource as defined in CEQA Guidelines Section 15064.5? c. Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature? d. Disturb any human remains, including those interred outside of formal cemeteries? e. Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either:

X X X X

1) a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American Tribe, that is listed or eligible for listing on the California Register of Historical Resources, or on a local register of historical resources as defined in Public Resources Code section 5020.1(k), or 2) a resource determined by a lead agency, in its discretion and supported by substantial evidence, to be significant according to the historical register criteria in Public Resources Code section 5024.1 (c), and considering the significance of the resource to a California Native American tribe.

The legislature added the new requirements regarding tribal cultural resources in Assembly Bill 52 (Gatto, 2014). By including tribal cultural resources early in the CEQA process, the legislature intended to ensure that local and Tribal governments, public agencies, and project proponents would have information available, early in the project planning process, to identify and address potential adverse impacts to tribal cultural resources. By taking this proactive approach, the legislature also intended to reduce the potential for delay and conflicts in the environmental review process. ((AB 52 § 1 (b)(7). Tribal consultation, if requested as provided in Public Resources Code Section 21080.3.1, must begin prior to release of a negative declaration, mitigated negative declaration, or environmental impact report for a project. Information provided through tribal consultation may inform the lead agency’s assessment as to whether tribal cultural resources are present, and the significance of any potential impacts to such resources. Prior to beginning consultation, lead agencies may request information from the Native American Heritage Commission regarding its Sacred Lands File, per Public Resources Code sections 5097.9 and 5097.94, as well as the California Historical Resources Information System administered by the California Office of Historic Preservation. The Public Resources Code now establishes that “[a] project with an effect that may cause a substantial adverse change in the significance of a tribal cultural resource is a project that may have a significant effect on the environment.” (Pub. Resources Code, § 21084.2.) To help determine whether a project may have such an effect, the Public Resources Code requires a lead agency to consult with any California Native American tribe that requests consultation and is traditionally and culturally affiliated with the geographic area of a proposed project. That consultation must take place prior to the determination of whether a negative declaration, mitigated negative declaration, or environmental impact report is required for a project. (Pub. Resources Code, § 21080.3.1.) If a lead agency determines that a project may cause a substantial adverse change to tribal cultural resources, the lead agency must consider measures to mitigate that impact. Public Resources Code §20184.3 (b)(2) provides examples of mitigation measures that lead agencies may consider to avoid or minimize impacts to tribal cultural resources. Appendix G of CEQA will be revised by the Natural Resources Agency by July 2016 to address impacts to tribal cultural resources. This discussion and newly added section “e” serves to comply with the new requirements.

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The NAHC was contacted on June 30, 2015, and responded August 5, 2015, indicating that no Sacred Lands or Traditional Cultural Properties were on record with their office within the project area of 0.5mile (0.8 km) surrounding the project. The NAHC provided a list of Tribal representatives affiliated with the area and advised further outreach with these individuals to obtain additional information pertaining to tribal cultural resources that could be a concern in this area. Letters have been transmitted to these individuals; however, no responses have been received to date. Should additional information be presented by the Tribes, this information will be provided to IID promptly; and, if necessary, the cultural resources report will be revised accordingly. The information provided in this section indicates that no tribal cultural resources are reported within the project area or surrounding area.; however, the information reviewed only represents the available information from the CHRIS and NAHC search and may not completely satisfy the lead agency requirements under Assembly Bill 52 (AB 52) with regard to Native American consultation regarding tribal cultural resources (TCRs). (Chambers Group, August, 2015). The lead state agency’s requirements under AB 52 will be considered complete when one of three scenarios is met: 1. After 30 days from receipt of letters requesting consultation, no requests have been received 2. Consultation yields agreement on mitigation measures for impacts to TCRs, and 3. After good faith, reasonable efforts at consultation, an agreement with Tribes cannot be met. At the date of this Initial Study, no requests for a consultation have been received. Less than significant impact. a) The Project will not a cause a substantial adverse change in the significance of a historical resource as defined in CEQA Guidelines Section 15064.5. There will be construction activities associated with the development of this project. The project proponents shall consult with the Regional Cultural Resources team, the State Historic Preservation Officer (SHPO), federally-recognized Tribes, and other interested parties. In the event that cultural resources are discovered during project construction, any ground disturbing activity shall be halted and the IID Cultural Resources Officer or qualified designee shall be notified immediately. State compliance measures provide that the project shall be reported to the State Historic Preservation Office in the annual report, prepared and submitted after the end of the current fiscal year. O t h e r w i s e , impacts to cultural resources are expected to be less than significant. b) The Project will not cause a substantial adverse change in the significance of an archeological resource as d efin ed i n C E Q A G uid elin es S ecti o n 15064.5. However, there will be construction activities associated with the development of the project. The project proponents shall consult with the Regional Cultural Resources team associated with the NWR CCP and, when appropriate, the State Historic Preservation Officer (SHPO), federally recognized Tribes, and other interested parties. Less than significant impact.

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c) The Project will not directly or indirectly destroy a unique paleontological resource site or unique geologic feature. A paleontological resources study and records search revealed that the Salton Seawater Marine Habitat project area was negative for fossil localities; however, the same study discovered that several fossil localities were identified in surficial lacustrine and fluvial deposits, beneath soil, of late Pleistocene or Holocene-age sediments in the vicinity of the project area. These fossil localities include extant species and are not considered significant; however, because the project area has not been previously surveyed for paleontological resources, a low probability remains that paleontological specimens could be present. Although this investigation presumes that the project will not impact scientifically significant fossil localities, a qualified paleontologist should be notified of the discoveries and assesses the scientific significance of any paleontological resources identified. (Chambers Group, 2015)

Prior to grading, IID staff will coordinate with the Regional Cultural Resources team and the appropriate Tribal governments when deemed necessary in accordance with all pertinent local, State and Federal regulations and requirements. Less than significant impact. d) The Project will not disturb any human remains, including those interred outside of formal cemeteries, as the project does not lie in an area known to have any human remains. Although finding human remains in the project area is extremely unlikely, IID staff would coordinate with the Regional Cultural Resources team and the appropriate Tribal governments in accordance with IID policy and other State and Federal regulations. Less than significant impact. e) The project will not cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 by either impacting a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American Tribe, that is listed or eligible for listing on the California Register of Historical Resources, or on a local register of historical resources as defined in Public Resources Code section 5020.1(k), or by impacting a resource determined by a lead agency, in its discretion and supported by substantial evidence, to be significant according to the historical register criteria in Public Resources Code section 5024.1 (c), and considering the significance of the resource to a California Native American tribe. Consultation attempts occurred over two different periods prior to the completion of this Initial Study, June 30, 2015 and late Summer/early Fall, 2015. The lead agency has complied with AB 32 by sending letters to the tribal representatives requesting consultation indicated by the list generated by the NAHC. No requests for consultation from tribal representatives have been received. Less than significant impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 6. GEOLOGY AND SOILS. Would the project: a. Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: i) Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42. ii) Strong seismic ground shaking? iii) Seismic-related ground failure, including liquefaction? iv) Landslides? b. Result in substantial soil erosion, loss of topsoil, or changes in topography or unstable soil conditions from excavation, grading, or fill? c. Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on-or off-site landslide, lateral spreading, subsidence, liquefaction or collapse? d. Be located on expansive soil, as defined in Table 18-1-B of the California Building Code (2013), creating substantial risks to life or property? e. Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater?

X X X X X X

X

X X

Geology. Soils in the Project area are comprised of alluvial and lacustrine sediments. Vertical soil profiles taken in the nearby Red Hill Bay wetlands restoration area indicate inter-bedded strata of sands, silts and clays to depths of greater than 1m (Landmark Consultants, Inc. 2013). No exposed bedrock occurs within the Project site, but the Project may have to utilize some rock from the adjacent Obsidian Butte quarry as a source of construction aggregates. A preliminary sample indicated that below a couple inches of barnacles in various locations, the substrate is very dense clay in several color layers with very low permeability of the adjacent seawater. Samples in one boring found dense clay to three feet below the surface, then soft wet sand and silt to ten feet below the surface.

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Geological Hazards. In the Coachella Valley, the North American and Pacific tectonic plates slide past one another along the San Andreas, San Jacinto, and other related faults. Scientists predict that the southern section of the San Andreas Fault, from the Coachella Valley to the Mojave Desert, will rupture in the next 30 years, producing an earthquake with an estimated magnitude of 7.2 to 8.1. (NWR-CCP, 2013, p 4-17.). According to Larsen and Reilinger (1991), “the Brawley Seismic Zone and the Imperial Valley are “undergoing rapidly changing tectonics.” The lowlands of the Imperial Valley include alluvial fans or cones, which originate at the mouth of major drainages and have created extensive and frequently intersecting deposition areas. These geologic and topographic features are essential to the fluvial erosion and sorting process that generates the wide range of sands and gravels located on the valley floor. On the lower portions of the valley floor and following the northwest/southeast gradient of the valley, sand dunes and sand fields have formed. Deposits in these areas shift and move over time, with intervening areas scoured clean by prevailing winds. (NWR-CCP, 2013, p 4-17.). a)

The Project is in the vicinity of the southern point of origin of the San Andreas Fault and the Brawley extension zone. This area is characterized by frequent seismic activity. However, the project will not involve any habitable structures or other features that could represent a threat, were they to fail during a seismic event. Thus, the project will not expose people or structures to potential substantial adver se effects, including the risk of loss, injury, or death. Less than significant impact. i) The Project will not cause or contribute to a rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist. (Refer to Division of Mines and Geology Special Publication 42). ii) Strong seismic ground shaking? Although the project area may be subject to strong ground shaking during a seismic event, the project does not contain any features that would represent a threat under these conditions. The project is a wetlands restoration project and will not have habitable structures or other features that may represent a threat to persons in the area during a seismic event. The proposed restoration project will not expose people or structures to strong seismic ground shaking. iii) Seismic-related ground failure, including liquefaction? In the case of a substantial seismic event resulting in failure of pond berms, the release of water from the ponds will be toward the Salton Sea lakebed. There will be no threat to structures, roads or any other facilities.

b) iv) Landslides? The proposed project will not increase the potential for landslides in or adjacent to the site, as the project is not in an area prone to landslides and is virtually flat. The Project will not result in substantial soil erosion, loss of topsoil, or changes in topography or unstable soil conditions from excavation, grading, or fill. The project will require constructions of berms and pads to create the ponds. Construction materials will be imported from the Obsidian Butte or other officially designated and permitted quarries in the area to obtain construction fill and aggregate. All construction will be on non wetted lake bed after the Salton Sea has fully receded from the pond base area. Any lake bed material excavated during construction will be held in a pile close to an existing dike and at least 200 feet from the nearest water course. The dikes and raised equipment set down area will be compacted during construction for stability. All soils exposed during construction will be periodically wetted to prevent wind erosion. Rip rap will be placed at the water facing outer base of construction to contain soils if heavy rains or high waves occur. Silt barriers will be placed around the dikes during construction to prevent runoff of dirt from the dikes if heavy rain occurs. Such rain is infrequent, but possible. In the course of construction, the sides of the dikes will be surfaced with already excavated rip rap from a local quarry to prevent erosion by wind, rain, or waves. The top of the dikes will be surfaced with gravel to prevent dust or sediment from eroding due to wind or rain and to facilitate access. No top soils occur on the project site as it is composed of sands, silts, clays, and the carbonate skeletons of fish and barnacles. Less than significant impact after mitigation.

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c) The Project is not located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslides, lateral spreading, subsidence, liquefaction or collapse. Soils underlying the two ponds, berms and pads are comprised of inter-bedded sediments, ranging from clays to sands and gravels. (Landmark, 2015). Such soils are prone to potential liquefaction as a result of strong seismic events. In the case of a substantial seismic event resulting in failure of pond berms as a result of liquefaction, the release of water from the ponds will be toward the Salton Sea lakebed, which is the source of that water. There will be no threat to structures, roads or any other facilities other than the pond berms themselves. The project will not result in potential significant adverse environmental impacts with respect to liquefaction of soils. Less than significant impact with mitigation. d) The Project is not located on expansive soil, as defined in Table 18-1-B of the California Building Code (2013), and will not result in substantial risks to life or property. No Impact.

7. GREENHOUSE GAS EMISSIONS: Would the project: a. Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment? b. Would the Project conflict with any applicable plan or policy or regulation adopted for the purpose of reducing the emissions of GHGs?

No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

e) The Project will not be installing or utilizing septic tanks or other wastewater disposal systems. No impact.

X

X

CEQA thresholds for lead agencies must always be established through a public hearing process. Imperial County has not established formal quantitative or qualitative thresholds through a public rulemaking process, but CEQA permits the lead agency to establish a project-specific threshold of significance if backed by substantial evidence, until such time as a formal threshold is approved. Neither the County of Imperial or Imperial County Air Pollution Control District (ICAPCD) has any specific plans, policies, nor regulations adopted for reducing the emissions of GHGs.

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Greenhouse Gas Emissions – The USFWS has not developed a quantitative threshold for determining whether a project’s greenhouse gas (GHG) emissions will have a significant effect on the environment, and no statewide threshold has been adopted by the State of California. The California Air Pollution Officers Association (CAPCOA), in its publication “CEQA & Climate Change: Evaluating and Addressing Greenhouse Gas Emissions from Projects Subject to the California Environmental Quality Act” (2008), does explore various options for establishing significance thresholds for GHG emissions. These options include setting the threshold at zero and setting a non-zero level for GHG emissions. Another option involves addressing project effects without establishing a threshold. This could be accomplished through a quantitative or qualitative evaluation of individual projects. Because significance thresholds for GHG emissions have yet to be established, our significance determination is currently based on the specific context of an individual action. To the extent possible, our determination is based on a quantitative evaluation of the effects of the action’s GHG emissions on the environment, including an estimate of the expected GHG emissions and the extent to which efforts are made to reduce expected emissions (NWR-CCP, 2013). Based upon GHG emission reduction guidelines established by San Bernardino and Riverside Counties, a project-specific threshold below 3,000 metric tons of CO2e per year was determined to be less than significant. Project-specific Screening Tables in the above GHG reduction plans identify open space and parks projects as less than significant. GHGs from construction activities shall be limited to the construction year only, with no emissions thereafter. a) The Project shall not generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment. The temporary increase of emissions of GHG associated with construction activities are not anticipated to significantly contribute incrementally to global climate change as GHGs would not increase beyond the construction phase of the project. Because those emissions would be temporary in nature and minor in magnitude, no significant exposure of people to risks associated with global climate change would occur. Less than significant impact. b) The Project would not conflict with any applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of GHGs. CEQA thresholds for lead agencies must always be established through a public hearing process. Imperial County and the ICAPCD have not established formal quantitative or qualitative thresholds through a public rulemaking process, but CEQA permits the lead agency to establish a project-specific threshold of significance if backed by substantial evidence, until such time as a formal threshold is approved. The temporary increase of emissions of GHG associated with construction activities are not anticipated to significantly contribute to global climate change as GHGs would not increase beyond the construction phase of the project. Because those emissions would be temporary in nature and minor in magnitude, no significant exposure of people to risks associated with global climate change would occur. Less than significant impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 8. HAZARDS AND HAZARDOUS MATERIALS: Would the project: a. Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials? b. Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment? c. Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? d. Be located on a site that is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5, and, as a result, would it create a significant hazard to the public or the environment? e. For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard for people residing or working in the project area? f. For a project located within the vicinity of a private airstrip, would the project result in a safety hazard for people residing or working in the project area?

X

X

X

X

X

X

g. I m p a i r implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan? h. Expose people or structures to a significant risk of loss, injury, or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands?

X X

The Project does not involve transportation, use or disposal of hazardous materials. The project will use water from the Salton Sea as make-up water for the solar pond and for the habitat pond. The solar pond will achieve design salinities of as much as 26% Total Dissolved Solids (TDS) in the Lower Convection Zone of the pond. The brine solution, although extremely salty, does not represent a hazardous waste; and even if released to the environment via a breach of the solar pond berm, the brine concentrate would be released back to the Salton Sea where it came from. No DTSC or reportable quantities of fuel or other hazardous materials will be kept on site. The pilot project may or may not be decommissioned at the end of the study period. If the pilot project is decommissioned, all hazardous elements related to the questions in this section will be complied with according to local, state, and federal regulations and laws.

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Solid Waste. The Resource Conservation and Recovery Act of 1976 is the principle Federal law governing the disposal of solid waste and hazardous waste (Title 40, Code of Federal Regulations, Part 14 260). This law establishes state responsibility for regulating nonhazardous wastes. It also addresses the generation, transportation, storage, and disposal of hazardous waste through a comprehensive “cradle-to-grave” system of hazardous waste management techniques and requirements. Although the USEPA is responsible for implementing the law, this task has been delegated to the California Department of Toxic Substances Control in California. The California Integrated Waste Management Act of 1989 (Assembly Bill [AB] 939) regulates nonhazardous solid waste and requires that solid waste generated in the State be reduced, recycled, and reused to the maximum extent feasible in an efficient and cost-effective manner to conserve natural resources, protect the environment, and improve landfill safety. Under this bill, cities and counties in California were required to reduce 50 percent of their waste stream by 2000. a) The Project would not create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials. Less than significant impact. b) The project will not create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment. Less than significant impact. c) The Project will not emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school, as nearest school is located approximately eight miles away. Less than significant impact. d) The Project is not located on a site that is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5, and, as a result, would not create a significant hazard to the public or the environment. The nearest area that appears on the State of CA Envirostor Hazardous Cleanup sites is a tiered permit site located at the CalEnergy – Elmore Facility located at 786 Sinclair Rd. near the intersection of Sinclair and Cox Rd. No impact. e) The Project is not located within an airport land use plan or, where such a plan has not been adopted, or within two miles of a public airport or public use airport. The project would not result in a safety hazard for people residing or working in the project area. No impact. f)

The project is not located within the vicinity of a private airstrip; the project would not result in a safety hazard for people residing or working in the project area. No impact.

g) The Project will not impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. The proposed project is a wetland restoration project and will not interfere with an adopted emergency response plan or emergency evacuation plan. No impact. h) The Project will not expose people or structures to a significant risk of loss, injury, or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands. The proposed project is a wetland restoration project that does not include significant quantities of flammable materials. No impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 9. HYDROLOGY AND WATER QUALITY. Would the project: a. Violate any water quality standards or waste discharge requirements? b. Substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g., the production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted)?

X X X

c. Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of stream or river, in a manner that would result in substantial erosion or siltation on- or off-site? d. Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site? e. Create or contribute runoff water, which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff? f. Otherwise substantially degrade water quality? g. Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map? h. Place within a 100-year flood hazard area structures that would impede or redirect flood flows? i. Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam? j. Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of sea level rise? k. Inundation by seiche, tsunami, or mudflow?

X

X X X X X X X X

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Project Overview. Implementation of this Project would include the construction of a set of berms across portions of the project site to form two 5-acre cells. This will require 4,636 linear feet of berms containing 87,500 cubic yards of compacted earth fill over a 19.6 acre base area for the two pond cells plus a raised water treatment equipment pad. If funding is not sufficient to construct two 5-acre cells in the near term, then two Ÿ acre cells will be constructed. The Ÿ acre cells will require 1,250 linear feet of berms containing 34,300 cubic yards of earth fill over a 2.3 acre base area inclusive of both ponds and a raised water treatment equipment pad. . The lined salinity gradient solar pond would hold impounded saline water at a target salinity equal to 26% TDS (total dissolved solids) in the bottom layer reducing to marine salinity on the upper layer. The berms will be 13 feet above the pond bottom with a 2:1 slope and a private gravel access road on the top. The working depth will range from 6 ½ feet at start up to a maximum of 12 feet as concentrated Salton Sea brine is added to the bottom layer. A buried network of small sample collection pipes and temperature probes will be installed at key locations under the bottom of the Salinity Gradient Solar Pond and Wildlife Habitat Pond and in the berm walls to monitor any leakage of brine and conduction of heat. So as to assure no leakage from the Solar Pond, the bottom and sides of the Salinity Gradient Solar Pond will be lined with polypropylene or other selected high temperature liner. The habitat pond with a six foot maximum depth would provide forage for fish eating birds and some diving birds in areas that have recently become exposed playa. If one or more nesting islands are installed, some habitat for wading birds and shorebirds in the currently exposed playa areas may also be available. The berms for both the habitat pond and the salinity solar gradient pond would be constructed using excavators, a dredge, and/or bulldozers. Additionally, the habitat pond would consist of loafing and nesting islands, snags for bird perches. Deeper water channels and culverts to support invertebrates (and potentially fish) would be constructed within the project site. a)

The water in both ponds will be continuously monitored for salinity and temperature at different depths and periodically sampled to analyze the water chemistry and biological activity. The bottom sediments of the Wildlife Habitat Pond and the berm between the ponds and soils around the ponds will be sampled for leakage of salts. The clarity of the Salinity Gradient Solar Pond water is critical and will be frequently monitored and corrected if needed by filtration, flocculation, additives or other means. Less than significant impact.

b)

The Project will not violate any water quality standards or waste discharge requirements. Preliminary permit research has determined that a Section 404 and a Section 401 of the Clean Water Act permits will be required. Based on the USACE determination that the Section 404 Ordinary High Water Mark is the average elevation of the Salton Sea from the previous year, the proposed project is located within the USACE jurisdictional boundaries and requires a Section 404 permit to allow the discharge of dredged or fill material into Waters of the U.S. A small return flow from the habitat pond back to the Salton Sea may be needed for nutrient management and salinity management purposes. This and any possibility of storm runoff carrying silt during construction require a Section 401 permit as well. Less than significant impact.

c)

The Project will not substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g., the production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted). The proposed project will acquire its water source from the Salton Sea. Less than significant impact.

d)

The Project will not substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of stream or river, in a manner that would result in substantial erosion or siltation on- or off-site. The project proposal incorporates a design that is consistent with the existing drainage pattern. No stream or river is on the site. Existing drainage is by flow across open playa, which will not be significantly altered. Preliminary permit research has determined that a CDFW Streambed Alteration Notification (Section 1602) will be required. Less than significant impact.

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e)

The Project will not create or contribute runoff water, which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. The proposed project is designed to manage all water on site, with the possible exception of a small return flow from the habitat pond back to the Salton Sea that may be needed for nutrient and salinity management purposes. The quality of this return flow will be the same or better than the Salton Sea water as it will be composed of Salton Sea water diluted by distilled Salton Sea water and the flow rate will be less than 131 gallons per minute, minute in comparison to the tens of thousands of gallons per minute of agricultural drain water that flows into the Salton Sea. Less than significant impact.

f)

The Project will not otherwise substantially degrade water quality. The water in both ponds will be continuously monitored for salinity and temperature at different depths and periodically sampled to analyze the water chemistry and biological activity. The bottom sediments of the Marine Habitat Pond and the dike between the ponds and soils around the ponds will be sampled for leakage of salts. The clarity of the Salinity Gradient Solar Pond water is critical and will be frequently monitored and corrected if needed by filtration, flocculation, additives or other means. Less than significant impact.

g)

The Project will not place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map. The proposed project is a pilot salinity gradient pond project and does not include housing development. Less than significant impact.

h)

The Project will not place within a 100-year flood hazard area structures that would impede or redirect flood flows. Berms and an equipment pad will be constructed on recently exposed Salton Sea playa that could be flooded in the event of a severe tropical storm or other 100 year flooding event; however these berms will abut an existing dike and are not in the path of any flood flows. Less than significant impact.

i)

The Project will not expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam. The proposed project consists of two small ponds adjacent to the Salton Sea and some associated water treatment equipment. Water in the ponds would flow would flow to the adjacent Salton Sea in the event of a flooding or berm failure. Less than significant impact.

j)

The Project would not expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of sea level rise. The proposed project is located adjacent to the Salton Sea, an arid inland sea which is not likely to experience sea level rise. If severe tropical storms similar to those the region experienced in the late 1970’s reoccur some rise of the Salton Sea level is possible. The berms and an equipment pad to be constructed on recently exposed Salton Sea playa will be a minimum of 8 feet higher than the playa surface, equal to or higher than an existing dike installed during the high stand of the modern Salton Sea. This will place site workers, equipment, equipment sheds, and any small structures above the reach of any flood within the last 100 years. Less than significant impact.

k) The Project is located near the San Andreas Fault and is directly adjacent to the Salton Sea. In the event of an earthquake, a seiche is possible. The berms and an equipment pad will be a minimum of 8 feet higher than the Salton Sea surface and will be faced with rip rap that can be expected to protect the berms and project equipment from all but a massive seiche. , If the berms failed or if sea water from a seiche overtopped them, then any release of waters within the project would be released to the Salton Sea. Less than significant impact.

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[

No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 10. LAND USE AND PLANNING. Would the project: a. Physically divide an established community? b. Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the project (including, but not limited to the general plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect? c. Conflict with any applicable habitat conservation plan or natural community conservation plan?

X X

X

The project is located within the Southern California Association of Governments (SCAG) metropolitan planning area, in Imperial County. The Imperial County Land Use Planning Document (2014) and the Imperial County General Plan provide planning policy for which the project must be consistent. Also, the Sony Bono Comprehensive Conservation Plan is a policy-planning document that has been adopted within the Salton Sea. a) The Project will not physically divide an established community. The proposed project is a wetland restoration project located within designated open space. No impact. b) According the Imperial County Land Use Planning Document (2014), the proposed project is located in Zone 53 in the Land Use Zoning District S1G (Open Space/Recreational). As detailed in the planning document, electrical energy facilities are an allowed land use within the S1G land use district with a Conditional Use Permit (CUP). The Project will not conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the project (including, but not limited to the general plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect. The proposed project is consistent with the Imperial County General Plan Land Use Map. No impact. c) The Project will not conflict with any applicable habitat conservation plan or natural community conservation plan. The Sonny Bono Comprehensive Conservation plan is the only Conservation plan in the area. While outside the boundaries of this plan, the proposed project is consistent with the goals of the SBCCP by restoring the habitat qualities of the Salton Sea in the 5-acre or Âź acre habitat pond. No impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 11. MINERAL RESOURCES. Would the project: a. Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state?

X

b. Result in the loss of availability of a locally important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan?

X

Minerals known to occur in Imperial County include gold, gypsum, sand, gravel, lime, clay, and stone (Imperial County 1993). A number of industrial materials are also extracted for commercial sale including kyanite, mineral fillers (e.g., clay, limestone, sericite, mica, and tuff), salt, potash, calcium chloride, manganese, and sand. There are a number of mining operations in Imperial County, but none are located near the project site (Imperial County 1993), nor are any significant deposits of these minerals or industrial materials known to occur within the project boundary. With respect to sand and gravel, the Imperial County General Plan (1993) indicates that there are limited suitable sand and gravel deposits within the County and none of the deposits are considered to be of exceptional quality or suitability. Another source of minerals is brine, a byproduct of geothermal activities. Minerals are extracted from brine only when it is cost effective to do so. The brine extracted during geothermal operations contains high levels of sodium, arsenic, antimony, mercury, selenium, potassium, iron, tin, manganese, chlorine, boron, bromine, potash, and zinc. Precious metals, such as silver, gold, and platinum, are also present in trace concentrations. Studies of brine in the Salton Sea area have shown substantial differences in the trace element compositions even from relatively closely spaced wells, and the total dissolved solids and mineral concentrations in the brine can change with the well flow rate (Imperial County 2006). Concentrated Salton Sea brine will go the bottom of the Salinity Gradient Solar Pond to increase the thermal storage capacity without brine discharge to the environment. This will demonstrate salinity management of Salton Sea habitat with beneficial use of both the distilled water and the salt. a) The Project would not result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state, as there are no known terrestrial deposits of the minerals that are known to occur near the project site. If solution mining from geothermal brine were contemplated at the site, the geothermal leaseholder already has geothermal wells slant drilled under the project site that could be used for the purpose. Currently the geothermal wells under the project site are used for reinjection of geothermal brine. The geothermal leaseholder approved use of this project site for a salinity gradient solar pond demonstration in 2010 because it has already been fully developed. No impact.

b) The Project will not result in the loss of availability of a locally important mineral resource

recovery site delineated on a local general plan, specific plan, or other land use plan, as there are no known deposits of minerals that are known to occur on or near the project site. No impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 12. NOISE. Would the project result in: a. Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? b. Exposure of persons to or generation of excessive groundborne vibration or groundborne noise levels?

X X

c. A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project? X d. A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the X project? e. For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public X airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels? f. For a project within the vicinity of a private airstrip, would the project expose people residing or working in the project area to X excessive noise levels? The activities proposed at the project site would generate noise well below applicable county noise standards as indicated in the Imperial County General Plan (1993). In addition, the project site is not located in proximity to any sensitive noise receptors (e.g., residential uses). a) The Project would not contribute exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies, as the construction of the project would generate noise well below the applicable noise standards. Less than significant impact. b) The Project would not contribute exposure of persons to or generation of excessive ground-borne vibration or ground-borne noise levels as the Project is a solar thermal desalination and managed aquatic habitat test project and is not going to create significant ground-borne vibrations through any of the construction or operation activities. Less than significant impact. c) The Project will not contribute substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project. The Project is a temporary test that will not cause any permanent increase in ambient noise. Less than significant impact

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d) The Project will not produce a substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project. Temporary construction activities will create an increase in ambient noise levels, which will subside once the project construction is completed. Operations will emit very little noise and will be at lower volume next to the Project site than temporary noise emitted by vented turbine steam from the geothermal power plant ½ mile away. The Project would not expose people residing or working in the project area to excessive noise levels. There are no residents within four miles of the Project site. Most workers in the area work at the several nearby geothermal plants which each have substantially higher noise levels than the Project will emit while operating. Less than significant impact. e) The Project is not located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport. The nearest municipal airport, Cliff Memorial Airport is located about ten miles away. No impact.

13. POPULATION AND HOUSING. Would the project: a. Induce substantial population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)? b. Displace substantial numbers of existing housing, necessitating the construction of replacement housing elsewhere? c. Displace substantial numbers of people, necessitating the construction of replacement housing elsewhere?

No Impact

Less Than Significant Impact

Less Than Significant Impa ct After Mitigatio n Incor porated

The Project is not located within the vicinity of a private airstrip, and would not expose people residing or working in the project area to excessive noise levels. No Impact.

Potentially Significant Impact

f)

X X X

a) The Project will not induce substantial population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure). The proposed project will construct two test ponds with associated desalination test equipment. The test equipment operators will not need to live on site as several towns are within a 30 minute drive. The Project does not include proposing new homes or improving roads or other infrastructure. No impact. b) The Project will not displace substantial numbers of existing housing, necessitating the construction of replacement housing elsewhere. The existing land is a playa, where an historical wetland existed. There are no homes in the project area. No impact.

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

c) The Project will not displace substantial numbers of people, necessitating the construction of replacement housing elsewhere. The Project will be constructed on a site that was recently under water, is not being used for housing, and has not been used for housing within the historical period. No impact.

14. PUBLIC SERVICES. a. Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services: i) Fire protection? X ii) Police protection? X iii) Schools? X iv) Parks? X v) Other public facilities? X Research. The project site could be used as a research facility (as a public facility) to monitor the effectiveness of the constructed habitat pond, as well as serve as a case study for the effectiveness of netting for avian exclusion. A gap exists in the literature surrounding avian mortality of solar gradient ponds. The site may help to establish research partnerships with academic institutions and other public, private, and non-profit researchers to conduct research that would benefit refuge management and/or refuge resources. a) The Project will not result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services. The project will have a very slight impact on the need for police and fire protection during operation in that three to four workers may be added to a police and fire service area that already has several hundred workers. The Project facilities will be constructed of steel, earth, and concrete, will not store significant amounts of flammable materials, and will not create a fire hazard: i. The Project proposes no changes to a local Fire Management Plan. ii. The Project would not require an increase in police protection. iii. The Project will not require additional alteration or construction of school facilities. iv. The Project will not result in any substantial adverse physical impacts associated with parks. v. The Project will not require surveillance by a private security company. Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact 15. RECREATION. a. Would the project increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?

X

b. Does the project include recreational facilities or require the construction or expansion of recreational facilities that might have an adverse physical effect on the environment?

X

a) The Project is not in the vicinity of any existing neighborhoods, regional parks, or recreational facilities. No impact.

16. TRANSPORTATION AND TRAFFIC. Would the project: a. Conflict with an applicable plan, ordinance or policy establishing measures of effectiveness for the performance of the circulation system, taking into account all modes of transportation including mass transit and non-motorized travel and relevant components of the circulation system, including but not limited to intersections, streets, highways and freeways, pedestrian and bicycle paths, and mass transit? b. Conflict with an applicable congestion management program, including, but not limited to level of service standards and travel demand measures, or other standards established by the county congestion management agency for designated roads or highways? c. Result in a change in air traffic patterns, including either an increase in traffic levels or a change in location that results in substantial safety risks?

Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea

X

X

X

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No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

b) The project does not include any recreational facilities, nor does it require the construction of expansion of recreational facilities. No impact.

d. Substantially increase hazards due to a design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?

X

e. Result in inadequate emergency access?

X

f. Result in inadequate parking capacity?

X

g. Conflict with adopted policies, plans, or programs regarding public transit, bicycle, or pedestrian facilities, or otherwise decrease the performance or safety of such facilities?

X

Access to the proposed project would occur via I-8, I-10, SR-86, and HWY 111 and various improved local roads and dirt roads, namely Lack and Lindsey roads. Although the shortest distance to access aggregate would be along the narrow access road to Obsidian Butte, it is intended that access will be obtained along the more circuitous road, making the route four miles instead of two. This will provide for less degradation to the area. Construction access would be limited in duration from less than 30 days to up to 90 days and would typically involve not more than 40 average daily one-way trips for construction workers and supply transport. Transport of berm fill materials and other construction materials may require up to 14 truck trips per day on local rural and industrial roads and on State highways over a pond construction period of approximately 200 days. The capacity of the state routes and local roads serving the construction sites is not anticipated to be exceeded. The local roads are currently used for farm vehicles and for industrial traffic supporting the geothermal plants, but are never congested. Construction activities are not anticipated to require any road closures or detours lasting more than several hours. Any temporary road closures that may be needed have readily accessible alternate routes. As such, the proposed project would not result in incompatible land use, or conflict with adopted policies, plans, or programs. The project also does not propose to alter any state or local roads or create a new land use that did not previously exist. For these reasons, traffic impacts during construction and operation would be less than significant. The closest public airports include Cliff Hatfield Memorial Airport (approximately 10 miles to the southeast); Brawley Municipal Airport (approximately 20 miles to the southeast), Salton Sea Airport (approximately 35 miles to the northwest traveling on the 86 and 78 interstates), and Imperial Airport (approximately 32 miles to the south . These airports are generally utilized by general aviation, air taxi, and for military purposes. Given the distance, the Proposed Action would not change air traffic patterns. a) The Project will not conflict with an applicable plan, ordinance or policy establishing measures of effectiveness for the performance of the circulation system, taking into account all modes of transportation including mass transit and non-motorized travel and relevant components of the circulation system, including but not limited to intersections, streets, highways and freeways, pedestrian and bicycle paths, and mass transit. Less than significant impact. b) The Project will not conflict with an applicable congestion management program, including, but not limited to level of service standards and travel demand measures, or other standards established by the county congestion management agency for designated roads or highways. The project is a solar desalination and managed habitat pond construction and operation test project within the Salton Sea open space. Less than significant impact.

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c) The Project will not result in a change in air traffic patterns, including either an increase in traffic levels or a change in location that results in substantial safety risks. The proposed project is not located within a designated air traffic pattern or flight path. Less than significant impact. d) The Project will not substantially increase hazards due to a design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment). The proposed project will not include any public access roads. Less than significant impact. e) The Project will not result in inadequate emergency access. The project will not interfere with emergency access. Less than significant impact. f)

The Project will not result in inadequate parking capacity. Less than significant impact.

17. UTILITIES AND SERVICE SYSTEMS. Would the project: a. Exceed wastewater treatment requirements of the applicable Regional Water Quality Control Board? b. Require or result in the construction of new water or wastewater treatment facilities or expansion of existing facilities, the construction of which could cause significant environmental effects? c. Require or result in the construction of new stormwater drainage facilities or expansion of existing facilities, the construction of which could cause significant environmental effects? d. Have sufficient water supplies available to serve the project from existing entitlements and resources, or are new or expanded entitlements needed? e. Result in a determination by the wastewater treatment provider that serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments? f. Be served by a landfill with sufficient permitted capacity to accommodate the project’s solid waste disposal needs? g. Comply with federal, state, and local statutes and regulations related to solid waste?

Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea

No Impact

Less Than Significant Impact

.

Less Than Significant Impact After Mitigation Incorporated

Potentially Significant Impact

g) The Project will not conflict with adopted policies, plans, or programs regarding public transit, bicycle, or pedestrian facilities, or otherwise decrease the performance or safety of such facilities. No such facilities or plans exist within the Project site. Less than significant impact.

X X X X X

X

X

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a) The Project will not exceed wastewater treatment requirements of the applicable Regional Water Quality Control Board. The proposed project will require a Section 401 permit Water Quality Certification from the Colorado River Basin Regional Water Quality Control Board. Less than significant impact. b) The Project will not require or result in the construction of new water or wastewater treatment facilities or expansion of existing facilities, the construction of which could cause significant environmental effects. The project proposal does not include a wastewater treatment facility as part of the project. The project will not produce a significant quantity of wastewater. The Project will include a desalination facility, but that will be used solely to improve the water quality of Salton Sea water for use in the habitat pond managed by the Project. The brine from the desalination facility will be used to supply the salinity gradient solar pond with no discharge to the environment or to any wastewater treatment facility. Less than significant impact. The Project will not require or result in the construction of new stormwater drainage facilities or expansion of existing facilities, the construction of which could cause significant environmental effects. The project proposal does not include a stormwater drainage facility or expansion of existing facilities, or its construction, nor will it increase or significantly alter the flow of storm water in the Project area. The Project will require extension of existing electrical power to the site. An existing utility power line comes to about 600 feet from the Project site to supply power to irrigation pumps. A 3-phase 480 Volt 225 Amp utility services will be added to the existing utility service on existing power poles. The 600 foot run to the project site will be installed in buried conduit next to the project site to eliminate visual impacts. The intake saltwater pump from the Sea will also require electrical power. Based on estimates of saltwater use, the equivalent of a 15-horsepower pump will be necessary. A compressed air pump will be used for safety in a saltwater environment driven by an onshore air compressor drawing from an extension to the electrical service already installed for the VTE Pilot Plant. Running underground conduit as a project level design prevents visual impacts. Using existing poles and existing service prevents the need to add new poles or lines. Less than significant impact. c) The Project will have sufficient water supplies available to serve the project from existing resources. No new or expanded entitlements will be needed. The project will receive its water from the Salton Sea under an existing agreement with the Colorado River Basin Regional Water Quality Control Board (RWQCB) and return any excess water to the Salton Sea under the terms of that agreement. If needed, any alterations to the existing agreement on the intake and return of Salton Sea water will be subject to the approval of the RWQCB and to the approval of the California Department of Fish and Wildlife with respect to any impacts on fish or birds. Less than significant impact. d) The Project will not result in a determination by the wastewater treatment provider that serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments. The Project will not have discharges to any sewer system. Human waste for workers on site will either be serviced off site at the CalEnergy geothermal plant or by rented portable toilets serviced by a licensed provider. Less than significant impact.

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e) The Project will be served by a landfill with sufficient permitted capacity to accommodate the project’s solid waste disposal needs. There may be an excess production of gypsum by the process used to concentrate Salton Sea salts for the salinity gradient solar pond. This material may be used in the pond, but if not, it will be transported to Cal Biomass in Thermal California for recycling. A maximum of three truckloads per month may be required for solid waste. For construction waste and any solid waste materials other than gypsum, trash collection and recycling services in the area are supplied by Allied Waste Management. Less than significant impact.

No Impact

Less Than Significant Impact

Less Than Significant Impact After Mitigation Incorporated

The Project will comply with federal, state, and local statutes and regulations related to solid waste. Imperial County currently operates ten Class III landfills (Imperial County 2008a). Trash collection and recycling services in the area are supplied by Allied Waste Management. Two Class I landfills are located in California: Safety Kleen’s Buttonwillow Landfill in Kern County and Chemical Waste Management’s Kettleman Hills Landfill in Kings County. Less than significant impact.

Potentially Significant Impact

f)

18. MANDATORY FINDINGS OF SIGNIFICANCE. a. Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below selfsustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or prehistory?

b. Does the project have impacts that are individually limited, but cumulatively considerable? “Cumulatively considerable” means that the incremental effects of a project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects.

c. Does the project have environmental effects that will cause substantial adverse effects on human beings, either directly or indirectly?

Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea

X

X

X

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a) The Project does not have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self- sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or prehistory. The primary objectives of the Project are three-fold: 1) demonstrate the technical feasibility of the salinity-gradient solar pond to produce thermal energy; 2) create and maintain wildlife habitat ponds around the desiccating shoreline of the Sea; and 3) cover the playa area with ponds and decrease particulate matter from becoming airborne during wind events as part of an integrated dust management program for the Sea. Up until recently, this area was inundated by the Salton Sea and supported a variety of aquatic organisms and migratory birds. Partly as a result of new conservation measures implemented in the Imperial Valley to conserve water for transport to the San Diego region, this portion of the Sea has receded exposing the sea floor and eliminating shallow water habitat. Less than significant impact. b) The Project does not have impacts that are individually limited, but cumulatively considerable. “Cumulatively considerable� means that the incremental effects of a project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects. The proposed project provides a design that aims to increase agricultural productivity and habitat values while minimizing dust and air quality issues related to the lack of water in the Salton Sea. There are no cumulative effects associated with the project as proposed. Less than significant impact.

c) The Project will not have environmental effects that will cause substantial adverse effects on human beings, either directly or indirectly. The proposed project is a solar desalination and managed habitat pond construction and operation test project that will test methods that may in the future provide the opportunity for humans to actively be connected with nature in a potentially resilient Salton Sea environment. The overall project provides a slight increase in environmental values during the term of operation. Less than significant impact.

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REFERENCES Appendix C. (2015). Construction Air Quality Impact Estimates. BLM. (2013). Ambient Air Quality Summary and Attainment Status. In Joint Environmental Assessment/Initial Study MND for the Path 42 Transmission Upgrades Project. http://www.blm.gov/pgdata/etc/medialib/blm/ca/pdf/palmsprings/nepa/iid_path_42.Par.72499.File.dat/ Path%2042%20Trans%20Line%20Upgrade%20EA.pdf. Retrieved February 1, 2014. California Department of Conservation. (2013). Farmland Mapping and Monitoring Program. http://www.conservation.ca.gov/dlrp/FMMP/Pages/Index.aspx. Retrieved February 10, 2014. California Department of Toxic Substances Control. (2013). Envirostor. http://www.envirostor.dtsc.ca.gov/public/mapfull.asp?global_id=&x=119&y=37&zl=18&ms=640,480&mt=m&findaddress=True&city=salton%20sea,%20ca&zip=&count y=&federal_superfund=true&state_response=true&voluntary_cleanup=true&school_cleanup=true&ca _site=true&tiered_permit=true&evaluation. Retrieved February 8, 2014. Cisneros, C. (2015). A cultural and paleontological resources assessment study: salton seawater marine habitat pilot project. Imperial County, CA. Chamber Group, Inc. Coachella Valley Water District. (2013). Available at: http://www.cvwd.org/. Accessed February 10, 2014. Colorado River Basin Regional Water Quality Control Board. (2006). Water Quality Control Plan, Colorado River Basin-Region 7. Includes amendments through June 2006. Crayon, Jack. (2015) Pers. comm. Email correspondence regarding desert pupfish monitoring results. CDFW. Edge Environmenntal, Inc. (2009). Pinon Ridge Project Environmental Report. Montrose County, Colorado. http://ulpeis.anl.gov/documents/dpeis/references/pdfs/Edge_Env_Inc_2009_Pinon_Ridge_Project_ER. pdf. Retrieved July 29, 2015. Federal Emergency Management Agency. (FEMA) (2008). Flood Insurance Rate Map Panels 060065C1615G and XX, effective date August 28, 2008. Available at FEMA Map Service Center: https://msc.fema.gov/webapp/wcs/stores/servlet/FemaWelcomeView?storeId=10001&catalogId=1000 1&langId=-1. Accessed February 2014. Harris, R. and R. Davis. (1998). Evaluation of the efficacy of products and techniques for airport bird control. Canada. Krantz, Tim, Zias-Roe, Shellie, Dubus, Jessie. Salton Sea Site Visit (March 12, 2015) Imperial County Planning and Development Department. (1993) General Plan. http://www.icpds.com/?pid=829. Retrieved February 1, 2014. Imperial County Planning & Development Services: Airport Land Use Compatibility Maps (2015) www.icpds.com/?pid=1195. Imperial County Planning and Development Department. (2011). Imperial County Planning & Development Services Department Cluster I Solar Power Project Draft Environmental Impact Report. Imperial Irrigation District Salton Sea Salinity Gradient Solar Pond Pilot: Salton Sea

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ftp://ftp.co.imperial.ca.us/icpds/eir/cluster-I-solar/12ch3-greenhouse-emissions.pdf. Retrieved February 10, 2013. Imperial Irrigation District. (2015). Biological Assessment. Prepared by: Kelly Bishop. Imperial Irrigation District. (2013). Water Conservation and Transfer Project and Draft Habitat Conservation Plan/Natural Communities Conservation Plan SEIS/SEIR. Landmark Consultants. (2015). Core Sample Study. Larsen, S., and R. Reilinger. (1991). Age constraints for the present fault configuration in the Imperial Valley California: Evidence for northwestward propagation of the Gulf of California Rift System. J. Geophys. Res., 96(B6), 10339-103346, doi:10-1029/91JB00618. Miller, Russell V. (1988). Mineral Land Classification: Aggregate Materials in the Palm Springs ProductionConsumption Region, Special Report 159. Office of State Printing. Riverside County. (2003). Riverside County General Plan. Adopted October 2003. Available at: http://www.rctlma. org/genplan/content/gp.aspx. Accessed February 10, 2014. Riverside County. (2012). Riverside County Greenhouse Gas Screening Tables. Schmid, Brian. (2013). E-mail correspondence. Formation Environmental, Air Quality Consultants/Salton Sea Sonny Bono Salton Sea National Wildlife Refuge Complex. (2013). Draft Comprehensive Conservation Plan and Environmental Assessment. Volume I.

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