Bowring Site Reconnaissance Report

Phase I Desk Study and Site Reconnaissance at Former Bowring Site, Eltham Road, Greenwich, Royal Borough of Greenwich, SE12 8EU for Mace Report Reference: LP001066 Report Date : 30th November 2015

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TABLE OF CONTENTS A

INTRODUCTION..............................................................................................................................6 1

Authority ..........................................................................................................................................6

2

Objective ..........................................................................................................................................6

3

Scope of Works ..............................................................................................................................6

4

Limitations ........................................................................................................................................7

B

PHASE I – Desk study........................................................................................................................9 5

Environmental Setting ....................................................................................................................9 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8

6

Site Location and Description ............................................................................................9 Geology ...................................................................................................................................9 Hydrogeology ...................................................................................................................... 10 Hydrology............................................................................................................................. 11 Flooding ................................................................................................................................ 11 Designated Environmentally Sensitive Sites ................................................................. 11 Ground Stability Hazards ................................................................................................. 12 Ground Workings, Mining, Extraction and Natural Cavities ................................... 12

Site Usage ...................................................................................................................................... 12 6.1 Current Land Use .............................................................................................................. 12 6.2 Site History .......................................................................................................................... 13 6.3 Site Walkover...................................................................................................................... 15 6.4 Unexploded Ordnance (UXO) ....................................................................................... 15 6.5 Waste Planning and Landfill Records............................................................................. 16 6.6 Other Regulatory Records .............................................................................................. 16 6.7 Radon .................................................................................................................................... 17 PRELIMINARY CONCEPTUAL SITE MODEL ......................................................................... 18

C 7

Environmental Risk Assessment .............................................................................................. 18 7.1 7.2 7.3 7.4 7.5 7.6

8

Conceptual Site Model (CSM)......................................................................................... 18 Sources ................................................................................................................................. 18 Receptors ............................................................................................................................. 20 Pathways and Potential Pollutant Linkages ................................................................... 20 Qualitative Risk Assessment of Pollutant Linkages .................................................... 20 Conclusions ......................................................................................................................... 21

Geotechnical Risk Assessment ................................................................................................. 21 8.1 8.2

Geotechnical Risk Register .............................................................................................. 21 Conclusions ......................................................................................................................... 21

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Recommendations for Intrusive Ground Investigation ...................................................... 22

APPENDIX A - Limitations APPENDIX B - Figures APPENDIX C – Site Photographs APPENDIX D – Historic Maps and Environmental Database Searches APPENDIX E – Preliminary UXO Desk Study APPENDIX F – Qualitative Risk Assessment Model APPENDIX G – Geotechnical Risk Register

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EXECUTIVE SUMMARY The site is located off Eltham Road in the Royal Borough of Greenwich and currently comprises a sports field located within a primarily residential setting. A pavilion is present on the site in the southeast corner along with two garages and sheds. A macadam car park is located in the southwest of the site.

It is proposed to redevelop the site with a new secondary school, the design and location of which is yet to be determined.

Geological mapping indicates that the underlying geology comprises the Kempton Park Gravel Formation over the London Clay Formation.

The Kempton Park Gravel Formation is classed as a secondary A aquifer. The site is located on the edge of a Groundwater Source Protection Zone two (outer) and three (total catchment). It is likely that this relates to abstraction from the underlying chalk aquifer.

Historically the site has always been open land or used as a sports field apart from a brief period between circa 1896 and 1916 when the southwestern portion of the site is shown to have been a nursery. The surrounding area started to be developed (primarily for housing) prior to the earliest records in 1864. Residential development has grown around the site over time with more commercial development to the southwest beyond Eltham Road. The location and configuration of the sports pavilions on site has changed overtime. Potentially contaminative adjacent land uses (either current or historical) include electrical substations, garage services, dry cleaners, a metal works, a print works and a bottle factory.

The Envirocheck report includes a record of inconclusive sand mining at the site, although no evidence was found from a review of the historic mapping to support this.

An unexploded ordnance (UXO) desk study has been completed. The desk study reports that the site was hit by 8 bombs, with a further 7 located within 50m of the site.

The qualitative risk assessment has identified primarily low to medium risks of ground contamination from the identified potential sources.

The following potential geotechnical hazards have also been identified:      

Likelihood of the presence of UXO (assessed as a substantial risk); Potential presence of an increased thickness of Made Ground, especially if former sand workings were present on site; Likelihood of the need to dewater excavations; Likelihood for high plasticity clays requiring deepened foundations, especially near trees; Potential for aggressive ground conditions; and Likelihood for soils remediation (likely to be limited to made ground removal/ relocation).

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A detailed UXO desk study is recommended, along with a geotechnical and geoenvironmental intrusive site investigation. The intrusive investigation should include excavation of boreholes across site, chemical and geotechnical laboratory testing of soils and the preparation of a quantitative contamination risk assessment.

Signed :

Paul Adams B.Sc. Ph.D. MIEnvSci.

Countersigned :

Helen Smith MSc CGeol DIC SiLC

Date :

30 November 2015

Revision:

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A INTRODUCTION 1

Authority

Leap Environmental Ltd (hereafter referred to as LEAP) has been appointed by Mace Group to undertake a Phase 1 Desk Study of a site referred to as ‘The Former Bowring Site’. A site location plan and red line boundary plan are provided in Appendix B. The instruction was received on 23rd November 2015 from Kati Pusey of Mace.

2

Objective

LEAP understands that the site is currently Metropolitan Open Land comprising a sports field, an existing sports pavilion and macadam hardstanding. It is proposed to construct a new secondary school comprising 6,800 square meters. LEAP understands that the location of the building on the wider site has not yet been confirmed and no design drawings have been provided to support this report.

The proposed development has been assessed in accordance with BS EN 19971, as being a Geotechnical Category 1 structure, assuming the building does not exceed 3 stories.

The objectives of this report are to: 

Provide information on the potential geotechnical and environmental quality of the ground present on the site;



Assess the potential health and other environmental risks posed by the site to the proposed development and to other specifically identified receptors; and



Assess the potential for offsite contamination to adversely affect the proposed development.

3

Scope of Works

This report presents the results of a desk study and site reconnaissance. The following sources of information have been reviewed: 

1

Envirocheck database report

BS EN 1997-1(2004) Eurocode 7:Geotechnical Design - Part 1:General Rules

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

Google Maps



‘What’s in Your Backyard’ Environment (http://maps.environment-agency.gov.uk/wiyby)



Envirocheck Historical map search



British Geological Survey (http://mapapps.bgs.ac.uk/geologyofbritain/home.html)



British Geological Survey website (www.bgs.ac.uk) including historic BGS borehole data



Unexploded WWII aerial delivered bomb (UXB) regional risk maps produced by Zetica



Preliminary Unexploded Ordnance (UXO) Risk Assessment, Landmark Information Group Ltd, ref. 75563998-1, issued 24th November 2015

Agency

(BGS)

Web

Search

mapping

The Envirocheck Dataset is included as Appendix D. The UXO Risk Assessment is included in Appendix E. A site reconnaissance was carried out on 27th November 2015. Photographs from this visit are included in Appendix C and findings are discussed in section 6.3.

The desk study and site reconnaissance have been used to develop an initial conceptual site model, which may be used to form the basis for an intrusive site investigation strategy, if required. The initial site conceptual model is used to identify geotechnical and geoenvironmental hazards and the qualitative degree of risk associated with them. In terms of the geoenvironmental assessment the conceptual site model is used to identify potential sources of contamination, potential receptors and pathways by which the two may be connected. These are known as possible pollutant linkages and it is these pollutant linkages that are key to contaminated land risk assessment.

The Phase I investigation is also referred to as a Preliminary Investigation2 .

4

Limitations

This report has been prepared by Leap Environmental Ltd on the basis of information received from a variety of sources which Leap Environmental Ltd believes to be accurate. Nevertheless,

2

BS 10175:2011 Investigation of Potentially Contaminated Sites – Code of Practice.

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Leap Environmental Ltd cannot and does not guarantee the authenticity or reliability of the information it has obtained from others.

Leap Environmental Ltd has used all reasonable skill, care and diligence in the design and execution of this report, taking into account the manpower and resources devoted to it in agreement with the Client. Although every reasonable effort has been made to obtain all relevant information, all potential contamination, environmental constraints or liabilities associated with the site may not necessarily have been revealed.

The conclusions reached in this report are necessarily restricted to those which can be determined from the information consulted and may be subject to amendment in the light of additional information becoming available. These conclusions may not be appropriate for alternative schemes.

This report is confidential to the Client, and Leap Environmental Ltd accepts no responsibility whatsoever to third parties to whom this report, or any part thereof, is made known, unless formally agreed by Leap Environmental Ltd beforehand. Any such party relies upon the report at their own risk.

Full details of the limitations are provided in Appendix A.

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B PHASE I – DESK STUDY 5

Environmental Setting

5.1 Site Location and Description The approximately 3.65 Ha site is located off Eltham Road, Greenwich, Royal Borough of Greenwich, SE12 8EU. Access to the site is via an unadopted road off Eltham Road.

The approximate National Grid Reference of the site is 540060, 175050. The site lies at an estimated elevation of approximately 18m Above Ordnance Datum (mAOD).

5.1.1

General Description and Boundaries

The site is located in a primarily residential area. Residential properties with gardens border the western boundary of the site beyond which is Meadowcourt Road and commercial property. To the north is the Quaggy River beyond which lies public open space. To the south of the site is primarily residential property and two places of worship. Beyond Eltham Road (the A20) are residential apartments with Leegate Shopping Centre to the southwest. To the east is Weigall Road sports field and Blackheath Park is located to the northeast.

The site is irregular in shape and occupies an area circa 210 m by 185 m at its widest points (excluding the access road). The site is ~95% grass soft standing and is used as a sports field.

The southwest corner of the site comprises a car park of macadam hardstanding. The sports pavilion is located in the south eastern corner of the site with two garages and two sheds immediately east of it.

A brick wall runs from west to east across the site to the immediate north of the car park and close to the northern extent of the sports pavilion. This wall demarks a no build zone as the area to the north can be flooded by the Environment Agency should the need arise to dam the River Quaggy.

5.2 Geology The geology of the site has been ascertained by reference to the 1:50,000 British Geological Survey, the BGS website (www.bgs.ac.uk) and the Envirocheck report. The site is mapped as being underlain by bedrock of the London Clay Formation, with overlying superficial deposits comprising the Kempton Park Gravel Formation.

5.2.1

Kempton Park Gravel Formation

Kempton Park Gravels are part of the former Flood Plain Gravel which is the youngest of the three River Terrace Gravels that were laid down by the Thames. The river terrace deposits consist of variable proportions of sand and gravel. They were deposited in a braided river system, an estimated 5km wide. Gravel dominated beds, generally less than 2m thick are cut through by broad shallow channels which are in-filled with tabular cross bedded gravelly sand

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in fining upward sequences. There are also impersistent beds of clayey and silty fine sand which are generally less than 1m thick.

5.2.2

London Clay Formation

The London Clay mainly comprises bioturbated or poorly laminated, blue-grey or grey-brown, slightly calcareous, silty to very silty clay, clayey silt and sometimes silt, with some layers of sandy clay. It commonly contains thin courses of carbonate concretions (‘cementstone nodules’) and disseminated pyrite. It also includes a few thin beds of shells and fine sand partings or pockets of sand, which commonly increase towards the base and towards the top of the formation. At the base, and at some other levels, thin beds of black rounded flint gravel occur in places. Glauconite is present in some of the sands and in some clay beds, and white mica occurs at some levels.

5.2.3

BGS Boreholes

The online BGS Geoindex (http://www.bgs.ac.uk/geoindex/) has been reviewed for detailed local geological and hydrogeological information. There are no records on borings on the site itself. The closets locations are TQ37SE473 (a borehole 9.14 m in depth) and TQ37SE74 (a trial pit 1.57 m in depth). Both these locations are situated circa 50 m southwest of the site.

Further borings are present further southwest and are associated with Leegate Shopping Centre (the nearest being TQ37SE720 located circa 100 m southwest of the site. The records indicate typically 0.3 m of made ground underlain by sandy loam or clayey gravel to no more than circa 1 m below ground level (bgl). Sands and gravels (if present at all) are underlain by brown, mottled grey or blue clay which is firm with occasional thin gravel bands to an unproven depth (at least 18.3 m bgl).

5.3 Hydrogeology The hydrogeology of the site has been ascertained from the Envirocheck data report and information from the Environment Agency’s ‘What’s in Your Backyard’ search. The source of the data is reported to be the Environment Agency groundwater vulnerability mapping.

The superficial deposit (Kempton Park Gravel) is designated as a secondary A aquifer. The bedrock (London Clay Formation) is designated as unproductive strata. The site is not located within Groundwater Source Protection Zone (SPZ) however the southern boundary lies on the immediate extremity of a zone 2 (outer protection zone) and zone 3 (total catchment).

There are no active or records of historical discharge consents or abstraction licenses within 500 m of the site. The site overlies soils of high leaching potential. It is anticipated that the SPZ relate to the underlying chalk aquifer.

Groundwater levels have been ascertained from the BGS Geoindex borehole logs referenced in section 5.2.3. Groundwater was noted within TQ37SE721 (located 180m south/southwest) at 7.6 m bgl, within the London Clay, and at 14.5m, within a gravel band. Groundwater was noted to rest at 0.76m bgl. Within TQ37SE701 (located 200 m southwest) groundwater was struck at 10.9m bgl.

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5.4 Hydrology There are no surface water features within the site. The River Quaggy runs along the northern site boundary. The River Quaggy is a primary river, which flows from east to west where it combines with the River Ravensbourne at Lewisham prior to flowing into Deptford Creek and ultimately the River Thames. The Envirocheck report also lists a number of drains and an extended culvert within 70m north of the site and Kid Brook approximately 285m northwest.

There is a flood gate on the River Quaggy immediately north of the site.

5.5 Flooding 5.5.1

Risk from Rivers

The information contained within the Envirocheck report and the Environment Agency website indicates that the majority of the northern region of the site is in flood zone 3 (defined as land assessed as having a 1 in 100 or greater annual probability of river flooding (>1%)). A small south easterly section of the site which is north of the wall is indicated to lie in flood zone 2 (defined as land assessed as having between a 1 in 100 and 1 in 1,000 annual probability of river flooding (1% – 0.1%)). The land to the south of the wall (which encompasses the sports pavilion, car park and access road) is indicated not to be at risk from flooding.

5.5.2

Risk from Surface Water

The information contained within the Envirocheck report and the Environment Agency website indicates that the majority of the site is at low risk (defined as land assessed as having between a 1 in 100 and 1 in 1,000 annual probability or 1% – 0.1%) of surface water flooding.

Extreme south eastern regions of the site are shown to be at a very low risk (defined as less than 1 in 1000 or 0.1%) of surface water flooding.

5.6 Designated Environmentally Sensitive Sites A review of designated environmentally sensitive sites presented within the Envirocheck report has been carried out. The dataset makes reference to a number of sensitive sites including the following:       

Sites of Special Scientific Interest (SSSI); Records of National Nature Reserves (NNR); Areas of Special Conservation (SAC); Records of Special Protection Areas (SPA); Records of Ramsar Sites; Records of Local Nature Reserves; Ancient Woodland Records.

None have been recorded within 500m of the site.

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LP001066 Former Bowring Site, Greenwich

Ground Stability Hazards

The Envirocheck report includes data from the National Geoscience Information Service (NGI) regarding the potential for certain ground stability hazards in the soil in certain locations. The ground stability information for the subject site is summarised as follows:-

Table 1 Ground Stability Hazard Risk Levels

Ground Stability Hazard

Collapsible Compressible Dissolution Landslide Running Sand Shrinking or swelling clay

NGI Reported Risk Level (Hazard potential) Very low No hazard No hazard Very low No hazard to low No hazard to moderate

These data indicate a low risk from ground stability hazards with the exception of shrinking or swelling clay which in some regions of the site is indicated as moderate. It should be noted that the actual risks from these hazards will be dependent on the ground conditions beneath the site which would need an intrusive investigation to be determined.

5.8

Ground Workings, Mining, Extraction and Natural Cavities

The Envirocheck report indicates that the site is not an in area affected by coal mining. An ‘inconclusive rock mining’ record within the site boundary is reported, although no information is provided for this designation and no evidence for mining activities is available from the historic mapping.

6

Site Usage

6.1 Current Land Use As discussed in section 5.1.1, the site is currently in use as a sports field and comprises a sports pavilion, garages and sheds in the south eastern corner, a car park (formally tennis courts) in the southwest and a river wall running west - east in the southern region of the site.

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There are 25 contemporary trade directory entries recorded within 250m of the site (and a further 9 within 500 m) by the Envirocheck database search. The most pertinent (within 250 m) are considered to be: a former car body repair shop located 80 m southwest, active garage services located 94, 102 and 115 m west, an active metal workers 97 m southeast, active dry cleaners 131 m west and 149 m southwest, an inactive dry cleaners 148 m southwest, a former printers 133 m west, former salvage dealers 150 m southwest, an inactive petrol filling station 187 m southwest and inactive garage services 190m southwest.

6.2 Site History The contaminative and development history of the site has been ascertained with reference to the historical plans as provided by the Envirocheck report and the Ordnance Survey historical maps provided from the National Library of Scotland.

6.2.1

Historical Map Evidence

The historical Ordnance Survey maps provided span the period from 1864 to present day at scales of 1:10,000, 1:2,500 and 1:1,250. The maps are included in full in Appendix D. Table 2: Summary of Historical Map Evidence

Year

On site

Surrounding area

1864

Undeveloped. Appears comprise open land.

1870-72

No change.

A railway and Lee station has been constructed circa 600m to the south.

1896

The eastern half of the site is shown as Gresham Athletic Ground and comprises two buildings on the western boundary. The south western quarter of the site is shown as a nursery with what are assumed to be glasshouses.

Further residential housing has been constructed to the south. Meadowcourt Road has been constructed to the west of the site. Ravensbourne Athletic Ground is shown to the east of the site and a cricket ground to the northeast.

to The major road network (which now comprises the B212 and the A20 – Eltham Road) is already present. Residential property is present to the west and southwest.

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Year

On site

Surrounding area

1916-20

The nursery is no longer shown Residential housing along Meadowcourt and the western half of the site Road has expanded and is now present is shown is Crownfield cricket adjacent to the western site boundary. ground and comprises a building in the southeast corner of this portion of land (in the vicinity of the current car park).

1946-49

The aerial photograph appears No significant changes noted. to show the cricket ground and sports field still present. A building has been constructed in the southeast corner in the location of the current sports pavilion.

1948-51

Site shown as a sports ground A bottle factory is shown circa 75m west (no longer divided into two). A of the site and engineering works shown total of five buildings are shown circa 200m west. in the southern regions of the site comprising two sports pavilions.

1962-73

The configuration of the buildings in the south has changed again with a larger building in the southeast corner shown as a sports club.

1969-85

No changes (although not all Former bottle factory / works now shown the site is shown). as a ‘Eurocentre’ with an electrical substation to the immediate west. Works circa 200m west now shown as a printing and engraving works. A garage is shown just south of the printers. An electrical

Residential property to the southeast has changed configuration and a car park is now present on the immediate south eastern boundary. Former bottle factory now shown as works. An electrical substation is shown circa 75m north.

Leegate Shopping Centre has been constructed circa 125m southwest of the site within which four electrical substations are shown.

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Year

On site

LP001066 Former Bowring Site, Greenwich

Surrounding area substation is shown 100m southeast of the site.

1991

Site layout appears as it is today No significant changes noted. with the car park shown as tennis courts.

1995-2015

No significant changes noted.

No significant changes noted.

Note: No 1:1,250 scale maps fully covering the site were available after 1991

6.3 Site Walkover It was observed during the site walkover undertaken on 27th November 2015 that the sports pavilion is now disused but is generally in a good state of repair as are the garages and sheds.

No access was available to any of the buildings apart from one of the two sheds which was found to contain furniture. Hence, the potential risk to land quality from the contents of the garages and sheds could not be ascertained. It was noted that both the garages appear to have a concrete hardstanding base which would offer protection from any spillages which may have occurred historically.

A number of concrete slabs were observed in the developed southern regions of the site suggesting that additional structures may have been present historically.

Cement asbestos sheeting and gas bottles were observed behind the pavilion building. Paint cans, a sit-on vehicle and a circa 205L open plastic drum of unidentified contents were observed around the garages along with small quantities of general waste in various locations across the site.

No signs of spills, staining, vegetative stress or invasive plants species were observed.

With the exception of the chain link fencing on the northern boundary, the boundary fencing was found to be in good condition.

6.4 Unexploded Ordnance (UXO) The risks from unexploded ordnance have been assessed in accordance with CIRIA guidance3.

A non-UXO specialist preliminary screening assessment has been carried out. The risks have been assessed by considering firstly the likelihood of military activities on, or in the vicinity of

3

CIRIA C681 2009. Unexploded ordnance (UXO) - A guide for the construction industry

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the site as determined from the desk study and historical review. Secondly the risk of UXO has been assessed by reference to the unexploded WWII aerial delivered bomb (UXB) regional risk maps produced by Zetica.

The Zetica risk maps indicate a moderate risk across the wider area, with the potential of 929 high explosive bombs and 52 incendiary bombs located over the whole vicinity of Greenwich to the north of the site. The bombsight website (www.bombsight.org) shows records of two bombs falling on the site itself and a number of further bombs falling in close vicinity.

A preliminary desk study from the Landmark Information Group4 was commissioned and it concludes a moderate (rating 3 out of 5) risk from UXO with 8 bombs having fallen on the site itself and a further 7 within 15m to 50m from the site boundary. The report recommends that avoidance measures are taken should any intrusive works be proposed.

6.5 Waste Planning and Landfill Records 6.5.1

Recorded Landfill Sites and Waste Management Facilities

The Environment Agency website and Envirocheck report contain details on areas of historic and active landfilling in the vicinity of the site.

No active or historical landfills, waste management facilities or waste transfer stations are shown within 500 m of the site.

6.6 Other Regulatory Records 6.6.1

Petrol and Fuel Stations

There are no active fuel stations located within 500 m of the site. The Envirocheck report contains a record of a historical filling station (Burnt Ash Service Station) 173 m southwest of the site.

6.6.2

Pollution incidents

There are three records of pollution to controlled waters within 250m of the site:   

A category 3/minor incident involving a miscellaneous/unknown pollutant on Meadowcourt Road, approximately 65m northwest of the site in 1993; A category 2/significant incident involving a miscellaneous/unknown pollutant, approximately 155m west of the site in 1992; and A category 3/minor incident involving oils on Weigall Road, approximately 155m northeast of the site in 1997.

4

Preliminary Unexploded Ordnance (UXO) Risk Assessment, Landmark Information Group Ltd, ref.

75563998-1, issued 24th November 2015

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6.7 Radon According to the Envirocheck database search, the site is not within a radon affected area (less than 1% of homes are above the action level for radon). Therefore, no special protective measures are required in the construction of buildings on this site, in respect of radon gas.

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C PRELIMINARY CONCEPTUAL SITE MODEL 7

Environmental Risk Assessment

7.1 Conceptual Site Model (CSM) A risk based approach is used to assess contaminated or potentially contaminated land within the UK. For a potential risk to exist, there must be a pollutant linkage in place, i.e. there must be a source of contamination, a potential receptor, and a pathway linking the two.

In order to quantify the magnitude of the risk, it is necessary to first calculate the potential exposure of the receptor as a result of all the individual active pollutant linkages affecting that receptor. Secondly it is necessary to ascertain “what is an acceptable exposure level for each of the identified receptors and contaminants?”.

The purpose of the Conceptual Site Model, in this instance, is to identify all of the potential pollutant linkages by considering, in turn, the potential sources, receptors and pathways.

7.2 Sources 7.2.1

Onsite Sources

Based on a review of the available site information the following contaminants of concern are proposed: Table 3: Onsite sources of contamination

Source

Potential Contaminants of Concern

Imported Made Ground – existing Polycyclic Aromatic Hydrocarbons (PAH) or former under buildings and under compounds and Petroleum Hydrocarbons (PHC) car parking area.

Heavy metals and asbestos Former nursery glasshouses

Asbestos, heavy metals, pesticides, PAH and PHC

Grounds keeping vehicles – fuel and PAH compounds and PHC oil from storage and maintenance Heavy metals

7.2.2

Offsite Sources

The desk study has highlighted the following potential off site sources of contamination:

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Table 4: Offsite sources of contamination

Source

Former printers

Distance from Site (m) 135 m to the west

Contaminants of Concern

Heavy metals, oils and VOCs

Active and inactive Car body repairs 80 PAH compounds and PHC garage services / car m to the southwest. body repairs Garage services – Heavy metals Active: 100m to the west. Inactive: 190m to the southwest Former bottle factor / 75m west ‘works’

PAH compounds and PHC, heavy metals Unknown

Active metal works

95m to southeast

the Heavy metals

Electrical Substations

Circa 75m north, Polychlorinated Biphenyls (PCBs) and 100m southeast and Mineral Oil four associated with shopping centre circa 125m southwest

Active and inactive dry Active: 130m west Trichloroethylene (TCE) cleaners and 150m to the southwest Inactive: 150m to the southwest Former salvage dealers 150m to southwest

the PAH compounds and PHC Heavy metals

Former petrol filling 190m to station southwest

the PAH compounds and PHC Heavy metals

These off-site sources are predominantly located to the southwest and west of the site. The River Quaggy is located to the north of the site, flowing to the west. As such, groundwater

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flow in the region of the site is anticipated to be towards the northwest. The identified offsite sources are thus not considered to be located hydraulically upgradient of the site and the risk posed by these sources on the site is considered to be low.

7.3 Receptors Potential receptors are those which may be impacted by any of the contaminants of concern identified above, and include the following:

Future site users, including pupils and staff;



Construction workers;



Groundwater within the Kempton Park Gravels (a Secondary A Aquifer);



Material construction of buildings and infrastructure; and



Neighbouring properties.

7.4 Pathways and Potential Pollutant Linkages The development is presumed to include areas of hardstanding, landscaped areas and playing fields. Potential pollutant linkages involving resident humans and soil contaminants will therefore be active, including direct dermal contact with soil, ingestion of dust and inhalation of vapours and dust indoors and outdoors. Finally ingestion of water carried by plastic water pipes through contaminated ground have been considered. Pathways associated with homegrown produce have not been considered.

Ground workers are at risk from all of the above.

The most sensitive human health receptor associated with the proposed development is considered to be the pupils.

The site is underlain by the Kempton Park Gravel Formation, a Secondary A aquifer. Hence there is a potential pathway for leachate from soil pollutants and for mobile liquid contaminants to enter the groundwater.

7.5

Qualitative Risk Assessment of Pollutant Linkages

Risk levels within the preliminary CSM are determined on a qualitative basis following review of the available desk-based information. The significance of particular pollutant linkages is dependant both upon the severity and likelihood of the risk.

The potential pollutant linkages are summarised in the table appended in Appendix F and given a qualitative risk classification in accordance with current guidance. The details of the risk assessment methodology are also presented in Appendix F.

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7.6 Conclusions The qualitative risk assessment has identified varying risks levels ranging primarily from low, to medium to future residents from the potential on site sources of contamination (PHC, PAH compounds, heavy metals and asbestos from made ground and former site usage). Primarily low to moderate risks from these potential sources have been identified to other receptors including construction workers, groundwater and building materials. Although a high risk from asbestos has been identified to construction workers and a high risk to future site users from inhalation of indoor dust and asbestos.

Low to risks from the potential off site sources of contamination, including print works, garages, substations, metal works and dry cleaners, have also been identified and are thus not considered further.

It is recommended that the risks posed from all the potential sources of contamination are quantified through an intrusive investigation, soils sampling, laboratory testing and through a quantitative risk assessment.

8

Geotechnical Risk Assessment

8.1 Geotechnical Risk Register The preliminary geotechnical risk register for the proposed development is summarised in the table in Appendix G.

8.2 Conclusions The following geotechnical hazards have been identified as significant:      

Likelihood of the presence of UXO (assessed as a substantial risk); Potential presence of an increased thickness of Made Ground, especially if former sand workings were present on site; Likelihood of the need to dewater excavations; Likelihood for high plasticity clays requiring deepened foundations, especially near trees; Potential for aggressive ground conditions; and Likelihood for soils remediation (likely to be limited to made ground removal/ relocation).

On the basis of the initial review and preliminary risk assessment, the site is given a Geotechnical Classification of Geotechnical Category 1 in accordance with EN1997-1 §2.1(14)-(21), assuming the school buildings do not exceed three stories in height.

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9

LP001066 Former Bowring Site, Greenwich

Recommendations for Intrusive Ground Investigation

Potentially significant pollutant linkages have been identified together with potential geotechnical hazards. It is therefore recommended that intrusive investigation is undertaken to quantify the risks. It is also recommended that additional UXO desk study be undertaken.

The initial investigation might comprise the excavation of dynamic sampler (‘windowless’) boreholes and or machine excavated trial pits across site to confirm ground conditions with chemical and geotechnical laboratory testing of soils. An allowance should be made for testing beneath the existing structures and hard standing. Should significant made ground, alluvium or peat deposits be found then deeper cable percussion boreholes will likely be required to provide foundation design parameters.

An allowance should be made for ground water level and potentially ground water quality monitoring. Also an allowance should be made for gas monitoring should significant made ground be encountered on site.

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APPENDIX A - LIMITATIONS

Limitations

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LIMITATIONS This report is confidential to the Client, and Leap Environmental Ltd accepts no responsibility whatsoever to third parties to whom this report, or any part thereof, is made known, unless formally agreed by Leap Environmental Ltd beforehand. Any such party relies upon the report at their own risk. Unless explicitly agreed otherwise in writing, this report has been prepared under LEAP’s standard terms and conditions, as included in the quotation for this works.

This report has been prepared by Leap Environmental Ltd on the basis of information received from a variety of sources which Leap Environmental Ltd believes to be accurate. Nevertheless, Leap Environmental Ltd cannot and does not guarantee the authenticity or reliability of the information it has obtained from others.

Leap Environmental Ltd has used all reasonable skill, care and diligence in the design and execution of this report, taking into account the manpower and resources devoted to it in agreement with the Client. Although every reasonable effort has been made to obtain all relevant information, all potential contamination, environmental constraints or liabilities associated with the site may not necessarily have been revealed. LEAP cannot be held responsible for any disclosures or changes in regulation that are provided post production of this report, and will not automatically update the report.

The conclusions reached in this report are necessarily restricted to those which can be determined from the information consulted, and may be subject to amendment in the light of additional information becoming available. These conclusions may not be appropriate for alternative schemes.

The presence of asbestos was noted during the site walkover survey. However, this report does not constitute an asbestos survey. On this basis, the presence of asbestos on site cannot be discounted and a full asbestos survey should be undertaken.

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APPENDIX B - FIGURES

Figures

Client :

Mace Group

Date :

30/11/15

Project ID:

LP001066

Project :

Former Bowring Site, Greenwich

Title :

Site Location Plan

Fig. No.

1

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APPENDIX C – SITE PHOTOGRAPHS

Photographs

Plate 1: Site entrance from Eltham Road

Plate 2: The pavilion building

Plate 3: View of the first shed and garage

Plate 4: View of the second shed and garage

Plate 5: Drum located between second shed Plate 6: Asbestos sheeting located behind and garage the pavilion

Plate 7: Gas bottles located behind the Plate 8: Vehicle amongst general waste in pavilion shed and garage region of the site

Plate 9: Car park area from the pavilion

Plate 10: View of the River Quaggy from just outside the NE site boundary

Plate 11: View of the River Quaggy flood Plate 12: Elevation change and flood storage area from inside the NW site defences in NW corner of the site boundary

Plate 13: View of sports field looking north Plate 14: Abandoned tractor in car park from site entrance area

Plate 15: Access to sports field around the Plate 16: View of the sports field looking flood protection wall east

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APPENDIX D – HISTORIC MAPS AND ENVIRONMENTAL DATABASE SEARCHES

Groundsure Historic Maps and GeoEnvironmental Data

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APPENDIX E – PRELIMINARY UXO DESK STUDY

Preliminary UXO Desk Study

Landmark Information Group Ltd Imperium, Imperial Way Reading, Berkshire RG2 0TD United Kingdom T: +44 (0)844 844 9952 W: www.envirocheck.co.uk

Preliminary Unexploded Ordnance (UXO) Risk Assessment Meeting the requirements of CIRIA C681 “Unexploded Ordnance (UXO) – A guide for the Construction Industry” Risk Management Framework

Site: 6, Hamlea Close, London, SE12 8EU Originator: Rachel Bullock Released By: Lisa Askham (24th November 2015)

6 Alpha Project Number: P4957 Landmark Order Number: 75563998_1 Client Reference: LP1066

Delivered By

www.envirocheck.co.uk - +44 (0) 844 844 9952 customerservice@envirocheck.co.uk

Unexploded Ordnance Probability Assessment Study Site The Study Site is described as “6, Hamlea Close, London, SE12 8EU”, and it is centred on National Grid Reference 540060, 175070.

Threat Potential UXO PROBABILITY ASSESSMENT = 3 RATING, INDICATING A MEDIUM PROBABILITY OF UXO ENCOUNTER The rating scale can be seen on Figure 2 (Probability of UXO Encounter). In accordance with current guidelines (CIRIA C681 Chapter 5), the highest risk rating has been determined at this specific site for UXO risk consideration and has been used for the final assessment and recommendations.

Summary During WWII the Study Site was situated within Metropolitan Boroughs of Woolwich, Greenwich and Lewisham, which recorded 183, 241 and 195 High Explosive (HE) bomb strikes per 1,000 acres respectively; all three are considered high levels of bombing.

Luftwaffe aerial reconnaissance photography associated with the Site identified a RAF supply depot (located 415m to the northeast) as a primary bombing target. In addition, a factory, railway station and works located in the vicinity may have been considered secondary bombing targets.

Air Raid Precaution (ARP) records identified eight HE bomb strikes within the Site. In addition, seven HE bomb strikes were identified within 50m of the Site boundary.

London County Council (LCC) bomb damage mapping recorded ‘Damaged beyond repair’ to a building on-Site and additional damage was recorded within the Site’s immediate vicinity.

The fact that bombing and bomb damage were recorded on-Site and within close proximity, would suggest that further action is warranted to address the potential for UXO encounter.

Recommendations In accordance with CIRIA C681 Chapter 5 on managing UXO risks, 6 Alpha recommends that the next stage in the risk management framework is:

DETAILED UXO THREAT & RISK ASSESSMENT We would be pleased to provide this service, please contact Envirocheck for further details: Telephone: +44 (0)844 844 9952

Email: customerservice@envirocheck.co.uk

Using This Report This Preliminary Assessment is designed to inform environmental and construction professionals of the potential threat of military related explosives and/or ordnance on, or in, the vicinity of the Study Site.

This assessment is designed to be employed as a site-screening tool to meet with the requirement of Phase One of the CIRIA UXO Risk Management Framework; there are two broad prospective outcomes; either the threat level requires a detailed UXO threat & risk assessment; or no further action is required. In the former instance we can provide a report within 10 working days (or more quickly upon application).

Two figures accompany the report, the Second World War (WWII) High Explosive (HE) Bomb Density and the final Probability of UXO Encounter. The purpose of this approach is to demonstrate that whilst bomb density statistics give an indication for WWII bombing, they should not be relied upon exclusively to generate a holistic assessment.

For further information, please contact Envirocheck:

Telephone: +44 (0)844 844 9952

Website: http://www.envirocheck.co.uk

Email: customerservice@envirocheck.co.uk

6 Alpha Project Number: P4957 Landmark Order Number: 75563998_1 Client Reference: LP1066

1

www.envirocheck.co.uk - +44 (0) 844 844 9952 customerservice@envirocheck.co.uk

Unexploded Ordnance Probability Assessment Data Findings Threat Source (Within 1,000m) Airfields/Military Facilities Ordnance Manufacture/Storage WWII Decoy Bombing Sites WWII Defensive Features WWII Luftwaffe Designated Bombing Targets

Detail Identified

    

Comments None recorded within 1,000m.

None recorded within 1,000m.

None recorded within 1,000m.

A barrage balloon centre was located 920m to the northeast.

Luftwaffe aerial photography identified a RAF supply depot (located 415m to the northeast) as a primary bombing target.

Secondary Bombing Targets



A factory (located 100m west), a railway station (660m south) and works (750m southwest).

WWII Bomb Strikes Within Site Boundary



ARP records identified eight HE bomb strikes within the Study Site.

WWII Bomb Strikes Near Site Boundary

   

ARP records identified seven HE bomb strikes within 15m and 50m of the Site boundary.

WWII Bomb Damage Abandoned Bomb Register WWII Bombing Density Per 1,000 Acres

Official bomb damage mapping recorded ‘Damaged beyond repair’ to an on-Site building.

The official abandoned bomb list did not identify any abandoned bombs within 1,000m.

Metropolitan Boroughs of Woolwich, Greenwich and Lewisham, all recorded 183, 241 and 195 HE bomb strikes per 1,000 acres.

Important Notes 1. The term ‘Preliminary UXO Risk Assessment’ has been used to describe this report, to fall inline with the CIRIA C681 guidelines. Whilst the term ‘Risk’ can be justifiably used at this stage, the reader should note that the ‘Consequence’ function of ‘Risk’ is not considered. Should it be required, this would be addressed in the ‘Detailed UXO Threat & Risk Assessment’ (Stages 2 and 3).

2. This report is accurate and up to date at the time of writing.

3. The assessment levels have been generated from historical data and third party sources. Where possible 6 Alpha have sought to verify the accuracy of such data, but cannot be held accountable for inherent errors that may be in third party data sets (e.g. National Archive or library sources).

4. 6 Alpha have exercised all reasonable care, skill and due diligence in producing this service.

5. Whilst every effort has been used to identify all potential UXO/explosive threats, there were a number of private facilities, which may not have released privately recorded information concerning UXO/explosive threats into the public domain. It is therefore possible that some of the aforementioned sites may not be included within the database.

6 Alpha Project Number: P4957 Landmark Order Number: 75563998_1 Client Reference: LP1066

2

www.envirocheck.co.uk - +44 (0) 844 844 9952 customerservice@envirocheck.co.uk

6, HAMLEA CLOSE, LONDON, SE12 8EU

WWIII High Explosive Bomb Density

BRITISH NATIONAL GRID

539900 0

20

540000 40

60

80

WWW.6ALPHA.COM

540100

540200

L

100

175200

175200

Metres

175100 175000

175000

175100

GREENWICH MET. B.

174900

174900

WOOLWICH MET. B.

LEGEND

Site_Boundary

High Explosive Bomb Density

Less than 50 bombs per 1000 acres 50-99 bombs per 1000 acres

LEWISHAM MET. B.

100-149 bombs per 1000 acres Over 200 bombs per 1000 acres 539900 P4957

PROJECT NO.

540000 1

FIGURE NO.

RG

DRAWN BY

RB

CHECKED BY

540100 23 November 2015 DATE

Contains Ordnance Survey data © Crown copyright and database right 2015

540200

174800

174800

150-199 bombs per 1000 acres

Produced by and Copyright to 6 Alpha Associates Ltd. Users noting any errors please notify 6 Alpha.

6, HAMLEA CLOSE, LONDON, SE12 8EU

Probability of UXO Encounter

BRITISH NATIONAL GRID

539900 0

20

540000 40

60

80

WWW.6ALPHA.COM

540100

540200

L

100

175200 175100 175000 174900

174900

175000

175100

175200

Metres

LEGEND

Site_Boundary

Probability of UXO Encounter 1 LOW 2

3 MODERATE 5 HIGH 539900 P4957

PROJECT NO.

540000 2

FIGURE NO.

RG

DRAWN BY

RB

CHECKED BY

540100 23 November 2015 DATE

Contains Ordnance Survey data © Crown copyright and database right 2015

540200

174800

174800

4

Produced by and Copyright to 6 Alpha Associates Ltd. Users noting any errors please notify 6 Alpha.

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APPENDIX F – QUALITATIVE RISK ASSESSMENT MODEL

Qualitative Risk Assessment Model

LP001066 - Former Bowring Site, Greenwich

Qualitative Risk Assessment of Pollutant Linkages Contaminant Polyaromatic Hydrocarbons, Petroleum Hydrocarbons

Receptor Future Site Users

Route 1

Pathway 1

Likelihood of Occurrence 2

Severity of Consequence

2

Risk Classification

1

Ingestion of soil

Likely

Medium

Moderate risk

2

Ingestion of indoor dust

Low likelihood

Medium

Moderate/low risk

5

High likelihood

Medium

High risk

6

Dermal contact with soil Dermal contact with indoor dust

Likely

Mild

Moderate/low risk

7

Inhalation of fugitive soil dust

Likely

Medium

Moderate risk

8

Inhalation of fugitive indoor dust Likely

Medium

Moderate risk

9

Inhalation of vapours outside

Unlikely

Medium

Low risk

10

Inhalation of vapours inside Inhalation of vapours via contaminated groundwater plume

Low likelihood

Medium

Moderate/low risk

Unlikely

Medium

Low risk

1

Ingestion of soil

Likely

Mild

Moderate/low risk

5

Dermal contact with soil

High likelihood

Mild

Moderate risk

7

Inhalation of fugitive soil dust

Likely

Mild

Moderate/low risk

9

Inhalation of vapours outside Intergranular flow of free product

Unlikely

Mild

Very low risk

Low likelihood

Medium

Moderate/low risk

Rainwater infiltration and leaching of contaminated soils

Likely

Mild

Moderate/low risk

Future Site Users and Neighbours

Notes Pathways involving dermal contact are more likely to occur, though would have less severe consequences.

The severity of the consequences is generally related to the levels of contamination present, which has been estimated from what we have determined about the site from the desk study. Concentrations of PAH compounds are considered likely to be highest and these are likely to be the key risk drivers.

Considered to be unlikely due to the lack of potentially contaminative historical land uses on site.

Construction workers

Groundwater

3

The risk posed to construction workers is limited to acute toxicity, which is considered to present a severe risk. However, the presence of contaminants in sufficient quantities to present an acute risk is considered to be low. Any risk would be mitigated through good construction and hygiene practises.

The consequence of controlled waters pollution is considered to be medium due to the sensitivity of receiving groundwater (a secondary A aquifer and proximity to SPZs). The potential for future contamination of groundwater is considered to be low due to the proposed land use, presence of hardstanding within the development and the likely removal of the majority of the made ground in soft standing areas which is likely to be the source of any contamination. Groundwater flow would be anticipated to be north towards the River Quaggy and away from the SPZs.

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LP01066 - Former Bowring Site, Greenwich

Contaminant

Receptor Surface water

Route 1

Pathway 1

Likelihood of Occurrence 2

Severity of Consequence

2

Risk Classification

Rainwater infiltration and leaching, intergranular flow via groundwater to controlled waters

Likely

Mild

Moderate/low risk

Surface water run-off

Unlikely

Mild

Very low risk

Material construction of buildings and infrastructure

Heavy Metals

Future Site Users

Likely

Mild

Moderate/low risk

1

Ingestion of soil

Likely

Medium

Moderate risk

2

Ingestion of indoor dust

Low likelihood

Medium

Moderate/low risk

5

Dermal contact with soil Dermal contact with indoor dust

High likelihood

Medium

High risk

Likely

Mild

Moderate/low risk

Likely

Medium

Moderate risk

8

Inhalation of fugative soil dust Inhalation of fugative indoor dust

Likely

Medium

Moderate risk

1

Ingestion of soil

Likely

Mild

Moderate/low risk

5

Dermal contact with soil

High likelihood

Mild

Moderate risk

7

Inhalation of fugative soil dust

Likely

Mild

Moderate/low risk

7

Construction workers

Groundwater Rainwater infiltration and leaching of contaminated soils

Notes The nearest surface water body is the Quaggy River The river is located adjacent to the northern boundary. For this reason the likelihood migration occurring is high but the likelihood of there being significant contamination is considered to be low.

Underground structures will be in prolonged contact with the ground however any made ground as well as the natural ground and groundwater are not considered likely to be significantly contaminated.

Groundwater is likely to be present at greater depth than the water supply pipes.

Contact of building materials, including water supply pipes with contaminated soils and/or contaminated groundwater

6

3

Low likelihood

Mild

Low risk

Pathways involving dermal contact are more likely to occur, though would have less severe consequences.

The severity of the consequences is generally related to the levels of contamination present, which has been estimated from what we have determined about the site from the desk study. Given the site history and that of the surrounding land uses significant heavy metal contamination in the soil is considered unlikely.

The risk posed to construction workers is considered to be moderate as the potential exposure and dust generation could be high. However, the exposure duration is anticipated to be short and risks could be mitigated through good construction practises and hygiene measures.

Mobilisation of metals is low, accept in acidic conditions. Significant heavy metal contamination in soils is considered unlikely.

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LP01066 - Former Bowring Site, Greenwich

Contaminant

Asbestos

Receptor Surface water

Route 1

Likelihood of Occurrence 2

Severity of Consequence

Pathway 1 Rainwater infiltration and leaching, intergranular flow via groundwater to controlled waters

2

Likely

Mild

Moderate/low risk

Surface water run-off

Unlikely

Mild

Very low risk

Inhalation of fugative soil dust Inhalation of fugative indoor dust

Likely

Severe

High risk

Likely

Severe

High risk

Risk Classification

Future Site Users 7 8 Construction workers

3

Notes Mobilisation of metals is low, accept in acidic conditions. The distance to the receptor is small however, significant heavy metal contamination in soils is considered unlikely.

Consequences of asbestos inhalation even at very low concentrations have the potential to be severe.

Asbestos could be present within any existing made ground.

Consequences of asbestos inhalation even at very low concentrations have the potential to be severe.

Asbestos could be present within the sports pavilion building and/or any existing made ground.

7

Inhalation of fugative soil dust

Likely

Severe

High risk

Notes to table: 1. Classification of human exposure pathways (routes) from The CLEA model, Research and Development Publication CLR10.

2. Classification of Probability and Consequence from CIRIA C552 Contaminated land risk assessment, a guide to good practice 2001 3. Risk Classification from DETR Guidelines for Environmental Risk Assessment and Management, 2000

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APPENDIX G – GEOTECHNICAL RISK REGISTER

Geotechnical Risk Register

LP001066 - Former Bowring Site, Greenwich

Preliminary Geotechnical Risk Register

Geotechnical risk is the risk to building and construction work created by the site ground conditions. The Preliminary Geotechnical Risk Register has been compiled to provide an assessment of the likely risks that may impact on the proposed development based on the results of the desk study, and should be used to specify the type and extent of the intrusive investigation and testing undertaken, and to identify potential mitigation measures to control the risk to an acceptable level.

The inclusion of a risk in the register does not indicate that the risk is present, rather the likelihood of mitigation measures being required due to that risk, based on the available data. Equally, a risk classified as low indicates that mitigation measures are unlikely to be required for the hazard identified based on the available data.

The risk register should be developed and refined throughout the design process such that it will enable the management of geotechnical risk.

The Geotechnical Risk Register has been developed in accordance with the guidance presented in ICE/DETR Document "Managing Geotechnical Risk" (2002). The degree of risk (R) is determined by assessing the likelihood of a hazard (L) occurring and the effect of the hazard (E) on the project (R=LxE). The effect may be measured in one or more aspect e.g. increased cost, delays in the program, health and safety etc. The scale of the likelihood, effect and risk are determined as follows:‐

Likelihood of Occurrence Scale

Likelihood

Chance

4

Probable

>1 in 2

3

Likely

2

Unlikely

1

Negligible

Effect of Hazard Scale

Effect

Increase in cost or time

4

Very High

>10%

1 in 10 to 1 in 2 1 in 100 to 1 in 10

3

High

2

<1 in 100

1

x

Degree of Risk Degree of Risk

Risk Level

Action required

1-4

Trivial

None

4-10%

5-8

Significant

Low

1-4%

9-12

Substantial

Consider cost effective solutions or improvements at no extra cost Work must not start until risk has been reduced. Additional resource required

Very Low

<1%

13-16

Intolerable

=

Work must not start until risk has been reduced. If risk can not be reduced, project should not proceed.

Page 1

Geotechnical Risk Register

Hazard Made Ground

LP001066 - Former Bowring Site, Greenwich

Effect Deepened foundations

Likelihood of Occurrence

Likely

Effect of Hazard

High

Risk Classification

Substantial

Unstable excavations

Compressible Ground

Negligible

High

Trivial

Negligible

Very high

Trivial

Envirocheck report indicates no hazard from compressible ground

Negligible

High

Trivial

Unlikely

High

Significant

Likely

High

Substantial

Contamination

Unlikely

Low

Trivial

Deepened foundations

Unlikely

High

Significant

Traffic Management

Negligible

High

Trivial

Bearing capacity failure

Unstable excavations/ running sands Dewatering

Deep Excavations Working in highway Shrinkable soils

Deepened foundations Likely

High

Substantial

Heave Frost Susceptible soils

Unlikely

Low

Trivial

Unlikely

Low

Trivial

Likely

High

Substantial

Negligible

High

Trivial

Negligible

High

Trivial

Unlikely

High

Significant

Negligible

High

Trivial

Negligible

High

Trivial

Unlikely

High

Significant

Remedial measures

Negligible

High

Trivial

UXO supervision

Likely

Very high

Road Design

Aggressive ground conditions for Concrete design Concrete Slope Stability/Retianing Structure Local stability Global stability Mining

Depth of MG unknown but footings from historical buildings may exist Thickness of made ground unknown but little anticipated.

BGS logs indicate less than 1 m of granular natural ground over London clay.

Excessive settlement High Groundwater Table

Notes

Envirocheck report indicates 'no hazard' to 'low' risk from running sands BGS records indicate DTW as 7.6-10.9 m bgl but maybe artesian and site is close to a river

Moderate risk in Envriocheck. Level of risk will depend on depth to London Clay.

Assessed as unlikely as it is assumed that no cutting (i.e. for a basement) will be required Will require determining during intrusive SI

Suitability for development

Site is flat.

A record is included in the Envirocheck report but is not shown on historic mapping

Ground dissolution/ Natural cavities Remedial measures Landfill Contaminated land Archaeological remains UXO

Land gas Remedial measures

Substantial

No landfills within 500 m Significant contamination considered unlikely given site history Zetica regional map indicates moderate risk

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Geotechnical Risk Register

LP001066 - Former Bowring Site, Greenwich

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