Remediation Method Statement Report Grange Road Cwmbran...

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Meritor Heavy Vehicle Braking Systems (UK) Limited Grange Road Cwmbran Gwent South Wales NP44 3XU Remediation Method Statement Report Grange Road Cwmbran Gwent South Wales NP44 3XU January 2011 909362819_01 Prepared by: ARCADIS (UK) Limited 2 Craven Court Newmarket CB8 7FA Tel: 01638 674767 Fax: 01638 668191 www.arcadis-uk.com

Transcript of Remediation Method Statement Report Grange Road Cwmbran...

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Meritor Heavy Vehicle Braking Systems (UK) LimitedGrange RoadCwmbranGwentSouth WalesNP44 3XU

Remediation Method Statement ReportGrange Road

CwmbranGwent

South WalesNP44 3XU

January 2011909362819_01

Prepared by:

ARCADIS (UK) Limited2 Craven CourtNewmarketCB8 7FATel: 01638 674767Fax: 01638 668191www.arcadis-uk.com

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Remediation Method Statement ReportMeritor HVBS (UK) Limited, Cwmbran

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Report Details

Client Meritor Heavy Vehicle Braking Systems (UK) Limited

Address Grange RoadCwmbranGwentSouth WalesNP44 3XU

Report Title Remediation Method Statement Report, Meritor HVBS (UK) Limited

Report Number 909362819_01

Report Date January 2011

Quality Assurance

Issue Number/Status Date Prepared By Technical Review Authorised by

01First Issue

January2011

Victoria MortenProject Manager

Mark WebbProject Director

Nicholas ReevesProject Director

If you have any queries regarding this project, please contact Victoria Morten.

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Remediation Method Statement ReportMeritor HVBS (UK) Limited, Cwmbran

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Table of Contents

1 INTRODUCTION ..........................................................................................11.1 Site Information .........................................................................................................11.2 Objectives..................................................................................................................11.3 Reliability of Information/ Limitations.........................................................................21.4 User Reliance ............................................................................................................2

2 PREVIOUS WORKS ....................................................................................32.1 ARCADIS 1998: Due Diligence .................................................................................32.2 ARCADIS 1998 – 2001: Storm Water Drainage System Improvements ..................32.3 ARCADIS 2000 – 2009 .............................................................................................42.4 ARCADIS 2009 - 2010 ..............................................................................................5

3 SITE CHARACTERISTICS ..........................................................................73.1 Location .....................................................................................................................73.2 Site Use History.........................................................................................................73.3 Environmental Setting .............................................................................................13

3.3.1 Topography.................................................................................................133.3.2 Regional Geology .......................................................................................133.3.3 Site-Specific Geology .................................................................................133.3.4 Groundwater Vulnerability ..........................................................................133.3.5 Groundwater Source Protection Zones ......................................................133.3.6 Groundwater Abstractions ..........................................................................133.3.7 Site-Specific Hydrogeology ........................................................................143.3.8 Hydrology....................................................................................................143.3.9 Flooding Risk ..............................................................................................153.3.10 Surface Water Abstractions........................................................................153.3.11 Sensitive Land-Uses...................................................................................15

3.4 Environmental Sensitivity ........................................................................................15

4 RELEVANT POLLUTANT LINKAGES ......................................................164.1 Future On-Site Commercial Worker ........................................................................164.2 Neighbouring Commercial Worker ..........................................................................164.3 Other Considered Scenarios ...................................................................................16

4.3.1 Off-Site Playing Fields Trespasser .............................................................164.3.2 Off-Site Playing Fields ................................................................................17

4.4 Water Resource Receptors .....................................................................................17

5 REMEDIATION STRATEGY ......................................................................185.1 Remediation Objectives ..........................................................................................185.2 Stakeholder Considerations ....................................................................................19

5.2.1 Site Owner ..................................................................................................195.2.2 Regulators ..................................................................................................195.2.3 Neighbouring Resident/ Property Owners..................................................19

5.3 Remediation Approach............................................................................................195.3.1 South-East Corner of Site & Southern Site Boundary................................195.3.2 South-Western Corner and Central & Southern Areas of Main ProductionBuilding and the Southern End of East Road..........................................................24

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6 SCOPE OF WORKS ..................................................................................266.1 Project Team ...........................................................................................................266.2 Remediation Phasing ..............................................................................................266.3 Task 1: Regulatory Interface ...................................................................................27

6.3.1 Abstraction Licences and Discharge Consents..........................................276.3.2 Waste Management Licensing ...................................................................28

6.4 Task 2: LNAPL and Impacted Groundwater Containment Pilot Testing – SouthernExtent of Site ........................................................................................................................286.5 Task 3: Baseline Groundwater Monitoring – Southern Extent of Site.....................286.6 Task 4: Remediation Method Statements & Remediation Implementation Plan ....296.7 Task 5: Implementation of a Full-Scale LNAPL and Impacted GroundwaterContainment Remediation System – Southern Extent of Site .............................................296.8 Task 6: System Mobilisation and Commissioning – Southern Extent of Site..........306.9 Task 7: System Operation, Monitoring and Maintenance – Southern Extent of Site316.10 Task 8: Groundwater Treatment via ERD Pilot Testing – Central Area of Site ......326.11 Task 9: Baseline Groundwater Monitoring – Full Extent of Site..............................326.12 Task 10: Implementation of a Full-Scale Groundwater Treatment Infrastructure –Central and Southern Areas of the Site ...............................................................................336.13 Task 11: System Mobilisation – Central and Southern Areas of the Site ...............336.14 Task 12: System Operation, Monitoring and Maintenance – Central and SouthernAreas of the Site...................................................................................................................336.15 Task 13: Investigation of Previously Inaccessible Areas of the Site– Central andSouthern Areas of the Site ...................................................................................................346.16 Task 14: Delineation and Remediation of Unexpected Impacts to Soil andGroundwater Quality Identified inn Previously Inaccessible Areas of the Site– Central andSouthern Areas of the Site ...................................................................................................356.17 Task 15: Post-Remediation Groundwater Monitoring .............................................356.18 Task 16: Remediation Closure ................................................................................36

7 SUMMARY .................................................................................................37

8 STUDY LIMITATIONS................................................................................38

Figures

1 Site Location Plan2 Site Layout Plan3 Proposed Remediation Schedule4 Proposed Remediation System Layout – Southern Extent of Site

Appendices

A Legislative Context and Regulatory Guidance

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List of Abbreviations that may be used in this report

ACM Asbestos Containing MaterialsARCADIS ARCADIS (UK) LimitedAST Above-ground Storage TankBGS British Geological SurveyBTEX Benzene, toluene, ethylbenzene and xylenesCDM Construction, Design and Management Regulations (2007)CoC Contaminants of ConcerncVOC Chlorinated Volatile Organic CompoundsDEFRA Department for Environment, Food and Rural AffairsDNAPL Dense Non-Aqueous Phase LiquidDQRA Detailed Quantitative Risk AssessmentEA Environment AgencyEC European CommunityEQS Environmental Quality StandardsERD Enhanced Reductive DechlorinationESA Environmental Site AssessmentGC-FID Gas Chromatography-Flame Ionisation DetectorGC-MS Gas Chromatography-Mass SpectrometerHGV Heavy Goods VehicleIC Ion ChromatographyIRZ In situ Reactive ZoneISCO In Situ Chemical OxidationLIF Laser Induced FluorescenceLNAPL Light Non-Aqueous Phase LiquidmAOD Metres Above Ordnance Datummbgl Metres below ground levelMCertS Monitoring Certification SchemeMeritor Meritor Heavy Vehicle Braking System (UK) LimitedMIP Membrane Interface ProbeMTBE Methyl tertiary-butyl etherNAPL Non-Aqueous Phase LiquidO&M Operation and MaintenanceOS Ordnance SurveyRMS Remediation Method StatementROA Remediation Options AppraisalSPZ Source Protection ZoneSSAC Site-Specific Assessment CriteriaSSSI Site of Special Scientific InterestSWDS Storm Water Drainage System

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TCE TrichloroetheneTPH Total Petroleum HydrocarbonsTPHCWG Total Petroleum Hydrocarbons Criteria Working GroupUKAS United Kingdom Accreditation ServiceUST Underground Storage TankVOC Volatile Organic Compounds

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1 INTRODUCTION

In December 2010, ARCADIS (UK) Limited (ARCADIS) was commissioned by Meritor HeavyVehicle Braking Systems (UK) Limited (Meritor) to prepare a Remediation Method Statement(RMS) for the redevelopment of their facility located on Grange Road, Cwmbran, Gwent,South Wales NP44 3XU(the site).

The RMS was conducted at the request of Meritor, who it is understood is divesting thenorthern two thirds of the freehold ownership of the site, including a parking area to the northof the main production building, for redevelopment for future commercial use.

The work was conducted in accordance with the Global Master Services Agreement (2008)between ARCADIS and ArvinMeritor Inc. The work was also performed in accordance withUK and Welsh legislation and regulatory guidance for the assessment of contaminated land,an overview of which is presented in Appendix A.

1.1 Site Information

Information from Ordnance Survey (OS) maps indicates that the site is located atNational Grid Reference ST 296951 on Grange Road, Cwmbran.

The site is located in an area of mixed land use that includes residential, light industrial andcommercial properties. The site is bounded by Grange Road to the west, Edlogan Way to thenorth, a railway line to the east and a factory to the south. The site lies on the flood plain ofthe Afon Lwyd, at an elevation of 55 metres Above Ordnance Datum (mAOD). Thetopography of the site is generally flat, although the area has a gentle gradient sloping to thesouth. There is a more distinct slope to the east towards the Afon Lwyd.

The majority of the site buildings were constructed in the 1930s to 1940s using a steel framestructure clad with metal sheeting. The facility is currently used for the manufacture of brakingsystems for heavy vehicles. The gross area of the facility is 25.73 acres. Beyond the railwaytrack to the east ArvinMeritor Inc lease a sports playing field. To the west beyondGrange Road lies residential housing and flats (approximately 80 m from the facilityboundary), and Cwmbran town centre. To the north lies a small industrial estate(approximately 300 m from facility boundary) and Cwmbran railway station. To the east,beyond the railway track lie sports playing fields, the Afon Lwyd and a school (approximately550 m from the facility boundary). To the South lies Crane Process Flow TechnologiesLimited, which manufactures valves. The grounds surrounding the facility comprise concreteand bituminous surfaced roads and pavements. There are small areas of open space to thewest consisting of gardens and roadside verges and the playing fields to the east.

The general site location and the physiogeographic features of the surrounding area arepresented on Figure 1 at a map scale of 1:50,000. The current site layout is presented onFigure 2.

1.2 Objectives

The objective of this report is to support the application for Planning Permission for theredevelopment of the Meritor Cwmbran facility.

The specific aims of this report are to:

Present a review of existing environmental data relating to the site; and, Provide a Remediation Method Statement outlining the environmental works to be

undertaken during and beyond the proposed site redevelopment.

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1.3 Reliability of Information/ Limitations

This report is only valid when read in its entirety. Any information or advice included in thisreport should not be relied on unless considered in the context of the whole report. Referenceshould be made to the notes on study limitations at the end of this report.

1.4 User Reliance

There are neither third party rights nor benefits conferred under this report. Use of this reportis strictly limited to Meritor and ArvinMeritor Inc and its direct and indirect subsidiaries, whichare the sole parties to whom ARCADIS intends to confer any rights. Any reliance on thecontents of this report by any other party is the sole responsibility of that party.

A copy of ARCADIS’ study limitations are presented in Section 8.

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2 PREVIOUS WORKS

Environmental works have been conducted on a voluntary basis by Meritor and aresummarised below.

2.1 ARCADIS 1998: Due Diligence

ARCADIS was first retained to review the environmental issues associated with the Cwmbranfacility following ArvinMeritor Inc’s acquisition of the site from Lucas Varity in November 1998.

ARCADIS was commissioned by ArvinMeritor Inc to conduct a Phase I Environmental SiteAssessment (ESA) of the site and to make and carry out recommendations of additional workto evaluate potential environmental liabilities that may be present at the facility. On completionof the Phase I ESA recommendations were made for an intrusive site investigation. ThePhase I ESA comprised a desk study and a site reconnaissance visit that was carried out byARCADIS between 21st and 22nd October 1998. The subsequent Phase II ESA wascompleted by ARCADIS between 23rd and 24th October 1998. The Phase II ESA comprisedthe progression of 13 boreholes. The majority of the boreholes were located along East Road,however two boreholes were located in the south-west corner of the site, in the vicinity of aformer petrol Underground Storage Tank (UST). Due to the ground conditions encounteredonly six of the 13 boreholes reached the target depth.

During the Phase I ESA, 11 USTs and 18 Above-ground Storage Tanks (ASTs) wereidentified at the site. The USTs were reportedly used for the storage of trichloroethene (TCE),waste oil, acid and alkali waste water and trade effluent. A reportedly decommissioned slurryfilled petrol UST was also present in the south-west corner of the site. The ASTs werereportedly used for the storage of fuel oil, waste and new oils, waste coolant oil, waste andclean TCE and ammonia. Many of the containment bunds were identified to be in poorcondition, with signs of deterioration or cracking, and there was evidence of spillage andstaining of the hardstanding. During the Phase I ESA two Storm Water Drainage Systems(SWDS) were identified beneath the site, the Northern and the Southern System, eachdraining roughly half of the site. Both SWDS discharged to the Afon Lwyd via a series ofinterceptors located on-site and in the adjacent playing fields. Site-staff stated, during thePhase I ESA, that a number of minor spills of TCE and oil had occurred, but no details of thelocations of the spills, the chemicals spilt or the amounts were available. It was reported thattwo asbestos surveys to identify Asbestos Containing Material (ACM) have been completedfor the site. The surveys identified at least 4 km of lagging that contained asbestos, togetherwith sheeting and tiles. Some ACMs had reportedly been removed, but ARCADIS wasinformed that no programme to remove the ACMs was in place.

During the Phase II ESA, limited soil and groundwater sampling undertaken, predominantlyalong the eastern site boundary. The analytical results and comparison to screening criteria,applicable at that time, indicated that the soil and groundwater samples (Alluvium only)beneath the site were impacted by TCE, vinyl chloride and total petroleum hydrocarbons(TPH) at concentrations above Dutch Intervention Values. The inferred groundwater flowwithin the Alluvium was toward the east and the Afon Lywd. None of the boreholes wereprogressed into the Raglan Marl Group underlying the Alluvium.

2.2 ARCADIS 1998 – 2001: Storm Water Drainage System Improvements

ARCADIS was retained by ArvinMeritor Inc to develop a remediation strategy for the sitefollowing the determination that certain contaminants referred to as List I substances(European Community (EC) Dangerous Substances Directive [76/464/EEC]) were enteringthe surface water course at concentrations above the relevant guideline values, referred to asEnvironmental Quality Standards (EQS).

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In brief, the remediation strategy included the following main work items:

A limited intrusive site investigation (including soil, groundwater, surface water and drainsediment sampling);

Detailed Closed Circuit Television (CCTV) inspection of the surface water drainagesystems;

Sampling and analysis of water and sediment samples from within the surface waterdrainage systems;

Cleaning of all drainage systems (high pressure water) and removal of sediments/sludges;

Review of operational activities at site with respect to storage and handling of hazardouschemicals (namely chlorinated solvents); and,

Discussions and negotiations with the regulators and selected stakeholders (WelshEnvironment Agency and Welsh Water).

2.3 ARCADIS 2000 – 2009

The SWDS improvement works resulted in a number of significant improvements, includingthe handling and storage of hazardous chemicals, the understanding of the location of thesurface water drainage systems, and the overall performance of the drains. Theseimprovements resulted in a reduction in the concentrations of site derived contaminantsentering the Afon Lwyd, however, concentrations of some List I substances continued in thedrain outfalls.

The conclusion of the SWDS improvement works identified that the integrity of the drainsacross much of the Cwmbran facility was questionable, and that at discrete locationsgroundwater was recorded (visual and flow data) to be entering the drains. The inference wasalso that where ground conditions permitted, drain effluent could possibly leak from thedrains. More significantly, the drains were acting as conduits to flow, resulting in the rapidtransmission of contaminated groundwater from the site into the surface water feature via thedrains. The assessment works, remediation works, and improvements in operational practicesresulted in a general reduction in contaminant concentrations in the outfalls, but theconcentrations measured in the two drainage discharge lines continued to exceed the EQSfor certain compounds. As such, detailed discussions with the regulators (Welsh EnvironmentAgency) resulted in an agreed interim strategy of monitoring and analysis of the flows andwater quality in the outfalls.

In August 2000, ArvinMeritor Inc submitted an application to the Environment Agency (EA) fora modification to the existing consents previously obtained by Lucas Varity (AB0075401 andAC0098101) for the discharge of site storm water to the Afon Lwyd. In September 2000, theEA requested additional monitoring data under Schedule 10 of the Water Resources Act1991. The schedule required ArvinMeritor Inc to provide an extra year of monitoring data fromthe date of the letter for the volatile organic compounds (VOC) previously detected in theoutfall. The EA stated that this should include low flow monitoring and approximately 48samples over the period of one year. The interim strategy of monitoring and analysis of theflows and water quality in the outfalls continued throughout 2000 – 2001. In February 2002,ARCADIS assisted in ensuring that ArvinMeritor Inc were granted two consents to dischargesurface water drainage into the Afon Lwyd by the EA, one for the Northern SWDS and one forthe Southern SWDS. Following the issue of the variations to discharge consents AB0075401and AC0098101 in 2002, Meritor proposed to the EA to reduce the monitoring schedule of 48samples per year from both discharge points to 24 samples per year from both the Northernand Southern outfall. This monitoring programme was agreed with the EA and continues todate.

ARCADIS has continued to assist ArvinMeritor Inc with the authorisations required todischarge storm water from the site since 2002. The consent for the Northern SWDS wasfurther modified, to a standard consent, in 2005. In the discharge consents, the EA requires

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monthly monitoring of VOCs, pH and total oil and grease in the storm water at the outfalls tothe Afon Lwyd. The data indicates generally reducing trends in the calculated 95th percentilesfor each compound in the Southern outfall during the period 1998-2007. However, thecalculated 95th percentile for both TCE and cis-1,2-dichloroethene (cis-1,2-DCE) haveincreased during the 2009 monitoring period at the Northern outfall. However, it should benoted that the calculated 95th percentiles for each of the SWDS for the 2009 monitoring periodare less than the calculated 95th percentiles for the overall monitoring period (1998-2009).

In October 2010, the discharge consents for the SWDS were superseded by the issue of twoEnvironment Permits, one for the Northern system (reference AC0098101/V001) and one forthe Southern system (reference AB0075401/V001).

2.4 ARCADIS 2009 - 2010

In December 2009, ARCADIS was commissioned to undertake an updated Phase I ESA ofthe site and to develop a scope of works for a subsequent Phase II ESA.

Phase I Environmental Site Assessment, Meritor Heavy Vehicle Braking Systems (UK)Limited, Cwmbran, ARCADIS January 2011.

Phase IIA Environmental Site Assessment Report, Meritor Heavy Vehicle BrakingSystems (UK) Limited, Cwmbran, ARCADIS January 2011.

Phase IIB Environmental Site Assessment Report, Meritor Heavy Vehicle BrakingSystems (UK) Limited, Cwmbran, ARCADIS January 2011.

Detailed Quantitative Risk Assessment (DQRA), Meritor Heavy Vehicle Braking Systems(UK) Limited, Cwmbran, ARCADIS January 2011.

Remediation Options Appraisal, Meritor Heavy Vehicle Braking Systems (UK) Limited,Cwmbran, ARCADIS January 2011.

A review of the analytical data for the soil and groundwater samples obtained from theboreholes and monitoring wells located across the site, indicated that shallow soil quality andgroundwater quality within the aquifer beneath the site had been impacted by site-derivedcontaminants. These contaminants included free-phase oil, TCE and its breakdown productsat concentrations above the GAC protective of human health and water resource receptors.Free-phase oil was identified along the eastern and south-eastern site boundary and withinthe main factory building. Based on the inferred groundwater flow direction ARCADISconsidered that there was potential for migration of the chlorinated VOC impacts andLight Non-Aqueous Phase Liquids (LNAPL) to the south-east towards the Afon Lwyd.

An assessment of the potential risks posed to human health and water resource receptorsrespectively was undertaken in the Detailed Quantitative Risk Assessment (DQRA). Theresults of the human health risk assessment undertaken, considering the measuredContaminants of Concern (CoC) concentrations in soil, groundwater and soil gas samples,indicate that the potential risk presented to potential future commercial workers is likely to beunacceptable. However, the assessment indicates that the potential risk presented to humanhealth, based on the redevelopment of the northern area of the site as a supermarket(including a petrol filling station), would be low. The results of the human health riskassessment, undertaken based on the potential risks presented to off-site receptors, alsoindicates that the potential risk presented to neighbouring commercial workers is potentiallyunacceptable. However, further investigations would be required to confirm this due to aseries of assumptions and a single dataset. However, the assessment of risk presented topotential trespassers accessing the adjacent playing fields indicates that the level of risk forthis scenario is likely to be low.

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The results of the water resource risk assessment, based on a commercial end-use, indicatesthat the potential risk presented to the identified water resource receptors is unacceptable.However, a number of conservative assumptions have been included within the modelling ofthis pathway. Therefore, additional monitoring and assessment of the CoC concentrationshydraulically down-gradient of the defined source areas may indicate that more attenuation isoccurring during the lateral migration of dissolved phase impacts than has been included inthe modelling.

Based on the results of the DQRA, it is considered that further works would be required inorder to appropriately manage the potential risks presented to human health and waterresource receptors, such that the site would be suitable for commercial redevelopment.

ARCADIS was subsequently commissioned by Meritor to undertake a Remediation OptionsAppraisal (ROA) for the site. It was understood that the northern employees’ car park is to bedivested and redeveloped as a supermarket and petrol filling station. None of the measuredconcentrations of CoC in soil and/ or groundwater samples exceeded the derived Site-Specific Assessment Criteria (SSAC) based on the future redevelopment of the northern partof the site for the end-use, therefore it has was not considered further in the report. ARCADISconsidered that the following technologies are most likely to achieve the remediationobjectives for the site and forms the basis for the outline remediation strategy.

Excavation and disposal of impacted shallow soil; LNAPL Removal; Potential Dense Non-Aqueous Phase Liquid (DNAPL) Removal; and, Groundwater containment and Treatment.

This report follows on from the works detailed in the reports detailed above.

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3 SITE CHARACTERISTICS

ARCADIS used information obtained from an inspection of the property, previousenvironmental works on-site and reference materials to formulate the property description.

3.1 Location

Information from OS maps indicates that the site is located at National Grid ReferenceST 296951 (National Grid co-ordinates 329684 195192) on Grange Road, Cwmbran, SouthWales.

The facility is located in an area of mixed land use that includes residential, light industrial andcommercial properties. The facility is bounded by Grange Road to the west, Edlogan Way tothe north, a railway line to the east and a factory to the south. The facility lies on the floodplain of the Afon Lwyd at an elevation of 55 mAOD. The topography of the facility is generallyflat with the immediately surrounding area sloping gently to the south.

The general site location and the physiogeographic features of the surrounding area arepresented on Figure 1, on a map scale of 1:50,000.

3.2 Site Use History

The historic use of the site was determined from inspection of 1:2,500, 1:10,000 and 1:10,560scale OS map extracts contained within the Envirocheck Report for the site produced byLandmark Information Group, dated December 2009, previous environmental worksundertaken at the site by ARCADIS, Information Obtained from www.Cwmbran.info andhistoric photographs.

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Date Site Use Potentially Contaminative Surrounding Land Use

Circa 1872 Joseph Lucas opened Tom Bowling Lamp Works in Birmingham, subsequently the JosephLucas Group diversified and began manufacturing automotive parts (www.Cwmbran.info).

1882

A railway line orientated north-south was located to the east adjacent to the site with the AfonLwyd beyond approximately 150 m from the site boundary. Llntarnam Grange andassociated clay pits were located approximately 100 m west of the site. A property indicatedto be White House was located approximately 400 m north of the site, but its use wasunknown from the map. Little Gelly was located approximately 200 m south of the site, butwas of unknown use. Cwmbran Brook was located approximately 700 m to the south of thesite. A second railway line was located to the west and south-west of the site with CwmbranJunction Station approximately 600 m to the south-west of the site.

1886

Approximately 1 km to the west of the site there was a factory manufacturing nuts and bolts.A gas works was located approximately 600 m to the west and a brick works locatedapproximately 1 km west, north-west of the site. Another brick works was locatedapproximately 1.5 km to the west, north-west of the site. Several tin works were located inthe vicinity of the site. Two tin works were located approximately 800 m to the north of thesite and a third was located approximately 800 m north-east of the site.

1901 to 1902

The road to the west of the site was indicated to be Grange Road. The outline of the clay pitsassociated with Llantarnam Grange had altered. Residential development had occurred tothe north of White House. Little Gelly is now indicated to be Little Gelli. Pant-y-herllan waslocated approximately 200 m west of the site, but its use could not be established from themap. The railway line was indicated to be the Pontypool, Caerleon & Newport Line. One ofthe tin works to the north of the site (Avondale works) was indicated to be a tin plating works.A clay pit was present to the north of the tin works. The tin works to the north-east of the siteis indicated to be ‘ruins’. The brick works located approximately 1.5 km to the west, north-west of the site to the north of the Holy Trinity Church is no longer indicated to be present,but a quarry remains to the south of the Holy Trinity Church. The brick works locatedapproximately 1 km west, north-west of the site is also indicated to be disused. The gasworks and bolt factory remain in the same locations.

1920 to 1921

The site was undeveloped agricultural land.

The clay pits associated with Llantarnam Grange had expanded. Further residentialdevelopment had occurred to the north and allotments were present approximately 800 m tothe north-east and 500 m north of the site. Further development of Little Gelli and Pant-y-herllan had occurred.

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Date Site Use Potentially Contaminative Surrounding Land Use

1922 The site was undeveloped agricultural landA stainless steel tube works is located to the north of the tin plate works in the formerlocation of the clay pit. The gas works and bolt factory remain. A large electricity sub-stationhad been developed to the east of the gas works.

1938

In 1938, Girlings and the Girling Brake wasacquired by the Joseph Lucas Group andthe engineering firm was relocated toCwmbran. Construction works for theCwmbran facility began in 1939, hamperedby winter weather and construction onlyoccurring in daylight due to lightingrestrictions imposed during the war(www.Cwmbran.info).

The tin works to the north of the site had expanded.

1939 to 1941

A large area of the production shop wascompleted in early 1941 and it beganreceiving machine tools between Februaryand March 1941. The Ministry of AircraftProduction operations at the site wereprimarily focused on producing andrefurbishing gun turrets for bomber aircraftduring World War II (www.Cwmbran.info).

Crane Process Flow Technologies Limited was established by Crane Company in April 2001through the acquisition of well known brands including Saunders Valve Works, Depa andRevo. In 1939, Saunders Valve Works was encouraged to establish a factory at Llantarnamby Government as a means of alleviating the effects of the recession in heavy industry duringthe 1930s. The Treasury reportedly provided a grant of £30,000 under the 1937 SpecialAreas Act to encourage Saunders Valve Works to construct the factory on Grange Road,Cwmbran. A historic photograph (Pontypool Museum, Photograph Reference TMS13029).shows the opening of the Saunders Valve Works in 1939. The factory remains on GrangeRoad and Crane Process Flow Technologies Limited currently undertakes the development,production and distribution of valves, actuation, pumps and related flow components. Thesite is owned by Alfa Laval.

1945

The site was occupied by the Ministry ofAircraft Production. Operations at the sitewere primarily focused on producing andrefurbishing gun turrets for bomber aircraftduring World War II. The main factorybuilding resembles the current layout.Auxiliary buildings are present to the southof the main factory building (including theformer boiler house). The roof of the factorybuilding is camouflaged.

No significant changes.

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Date Site Use Potentially Contaminative Surrounding Land Use

1946

A historic photograph (Central Register ofAerial Photography for Wales, PhotographReference CPE UK 1828 #4122 dated 4th

November 1946) indicates that the mainfactory building resembles the currentlayout. Auxiliary buildings are present to thesouth of the main factory building, includingthe former boiler house. The roof of thefactory building is camouflaged. The areacurrently occupied by the car park to thenorth of the site is an open grassed area.The site was occupied by the Ministry ofAircraft Production. Operations at the sitewere primarily focused on producing andrefurbishing gun turrets for bomber aircraftduring World War II. Between 1946 and1968, Lucas Girlings produced car brakes,master cylinders, actuators, shockabsorbers, Heavy Goods Vehicle (HGV)brakes and brakes for plant and agriculturalmachinery. These processes continued until1996 when the Lucas Company mergedwith the American company Varity to formLucas Varity Plc (www.Cwmbran.info).

1949

The site was occupied by Lucas Girlingsand was utilised for the production of carbrakes, master cylinders, actuators, shockabsorbers, HGV brakes and brakes for plantand agricultural machinery (e.g. tractors).The roof of the factory building iscamouflaged (Central Register of AerialPhotography for Wales, PhotographReference 540 RAF 205 #5006 dated 10th

May 1949).

No significant changes.

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Date Site Use Potentially Contaminative Surrounding Land Use

1954 to 1955

The site was a facility used for themanufacturing of braking systems for heavyand light vehicles. The site was occupied byLucas Girlings. The roof of the factorybuilding is camouflaged (Central Register ofAerial Photography for Wales, PhotographReference 58 RAF 1104 #27 dated10th March 1955).

No significant changes.

1962 to 1968

Significant residential development has occurred to the north, north-west, west and south-west of the site. A road, Edogan Way, and associated embankment has been constructedimmediately north of the site. A bus depot and associated tanks was present approximately400 m to the north-west of the site. Lantarnam Grange was indicated to be ‘ruins’ and thearea formerly occupied by the clay pits was undeveloped grassland. Buildings locatedimmediately to the south of the site were referred to as works. The bolt factory was nowindicated to be a works. The tin plating works to the north of the site are indicated to be a‘works’ with Avondale Hostel in the location of the former tin works.

1971 to 1973

The residential properties to the north of the bus depot have been demolished and a clothingfactory developed. Lantarnam Grange was indicated to be an arts centre. A multi-storey carpark was present immediately north of Lantarnam Grange. The works to the south of the sitewere indicated to be an Engineering works. A contractors yard, tanks and residentialproperties associated with the works were present.

1983 - 1985

The site was a facility used for themanufacturing of braking systems for heavyand light vehicles. The northern area of thesite is utilised for car parking and as arecreational sports ground with tenniscourts and a bowling green. The southernarea of the site housed auxiliary buildingsincluding the former boiler house (CentralRegister of Aerial Photography for Wales,Photograph Reference 58 RAF 5502 F22#146 dated 3rd October 1962, CentralRegister of Aerial Photography for Wales,Photograph Reference BKS 157767 dated6th July 1971 and Royal Commission on theAncient and Historical Monuments of Wales,Photograph Reference Ordnance Survey 79129 and Central Register of AerialPhotography for Wales, PhotographReference OS79129 #048 dated22nd September 1979). By 1973 the facilitywas referred to as a brake factory.

During the early 1980s significant residential development occurred in the area with theconstruction of Cwmbran new town. Car parking and retail facilities have been developed tothe west of the site.

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Date Site Use Potentially Contaminative Surrounding Land Use

1993 to 1994

The site is occupied by Meritor andresembles the current layout but the boilerhouse and stores to the south of the mainfactory building remain in situ. The sitecontinued to be used for the manufacturingof braking systems for vehicles (RoyalCommission on the Ancient and HistoricalMonuments of Wales, PhotographReferences 92_CS-0194 & 92_CS-0195).

Cwmbran railway station was located to the north of the site and Edogan Way, beyond whichwas an industrial estate. The bus depot is indicated to be a depot only. A youth centre waslocated to the north of the multi-storey car park with shops and further car parking to thewest. Lantarnam Grange remains as an arts centre. The outline of the works buildings hadaltered but the works remained. Several electrical sub-stations were indicated to be presentthroughout the works. The significant residential development and construction of Cwmbrannew town, including car parking and retail facilities that occurred in the 1980s to 1990s isevident in the historic photograph.

1999

The site is occupied by Meritor andresembles the current layout but the boilerhouse and stores to the south of the mainfactory building remain in situ. The sitecontinued to be used for the manufacturingof braking systems for vehicles.

The tin works and hostel to the north of the site have been demolished and the AvondaleIndustrial Estate and depot have been constructed. A timber yard was present immediatelysouth-east of Avondale Industrial Estate with a works located beyond the Afon Lwyd. Thegas works and works located in the vicinity of the former bolt factory have been incorporatedinto the Forge Hammer Industrial Estate beyond the car parking area and retail units to thewest of the site.

2000 to 2006

2009The production of trailer axels was added tothe site.

The works to the south-east of the timber yard have been redeveloped as residentialproperties. The gas works is no longer present within the Forge Hammer Industrial Estate.Further residential development has occurred in the area surrounding the ArvinMeritor site.(Central Register of Aerial Photography for Wales, Photograph Reference Getmapping2000/01 and Royal Commission on the Ancient and Historical Monuments of Wales,Photograph References 2001/5074-52 & 2001/5074-52).

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3.3 Environmental Setting

3.3.1 Topography

The facility lies on the flood plain of the Afon Lwyd at an elevation of 55 mAOD. Thetopography of the facility is generally flat, although the ground level of the surrounding area issloping gently to the south.

3.3.2 Regional Geology

A review of the 1:50,000 scale British Geological Survey (BGS) solid geological map(Sheet Number 249, Newport, 1975) indicates that the site is underlain by the Raglan MarlGroup within the Old Red Sandstone Formation. The Raglan Marl Group consists of fine-grained, well-cemented sandstone which gently dips to the west.

3.3.3 Site-Specific Geology

ARCADIS Site Investigation 2010The ground conditions encountered beneath the site consisted of concrete (or gravelly orclayey soils in certain locations) overlying Made Ground consisting of gravelly clay and clayeyor gravelly sand. The Made Ground contained fragments of brick and concrete withoccasional metal fragments proven to a maximum depth of 2.4 metres below ground level(mbgl). Several shallow refusals were also encountered within the shallow Made Grounddeposits. The Made Ground was underlain by sandy or gravelly clay and clayey or gravellysand with occasional cobbles, proven to a maximum depth of 4.8 mbgl. This was overlyingsandy gravel and cobbles of sandstone proved to a maximum depth of 6.0 mbgl. Thesedeposits are considered representative of alluvial deposits as shown on maps in the vicinity ofthe site. The Alluvium deposits were underlain by mudstone in several boreholes, proven to amaximum depth of 6.3 mbgl. The mudstone is considered to be representative of theRaglan Marl Group as identified in the desk-based study to be underlying the Alluvium. TheAlluvium deposits were underlain by mudstone with bands of sandstone and siltstone, provento a maximum depth of 33 mbgl. The mudstone and sandstone was considered to berepresentative of the Raglan Marl Group as identified in the desk-based study to beunderlying the Alluvium. The ground conditions encountered beneath the adjacent playingfields consisted of similar conditions to those encountered on-site.

3.3.4 Groundwater Vulnerability

The EA website (www.environment–agency.gov.uk) indicates that the Alluvium and theRaglan Marl Group underlying the site are classified as Secondary Aquifers.Secondary Aquifers include a wide range of rock layers or drift deposits with an equally widerange of water permeability and storage. Secondary aquifers are subdivided into two types Aand B. Both the Alluvium and the Raglan Marl Group are classified as Secondary Aquifer A,indicating they have permeable layers capable of supporting water supplies at a local ratherthan strategic scale, and in some cases forming an important source of base flow to rivers.

3.3.5 Groundwater Source Protection Zones

The digital groundwater Source Protection Zone (SPZ) Data Register accessed inDecember 2010 indicates that site is not located within a groundwater SPZ, as defined by theEA.

3.3.6 Groundwater Abstractions

The Envirocheck® Report provides no record of licensed groundwater abstractions locatedwithin a 2 km radius of the site.

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3.3.7 Site-Specific Hydrogeology

ARCADIS Site Investigation 2010The groundwater elevation data suggest a groundwater flow direction to the south andsouth-east within the Alluvium towards the Afon Lwyd. The flow direction has been inferred attwo depths within the Raglan Marl Group based on monitoring installations with similarscreened intervals. Based on the groundwater elevations in the monitoring wells screened atapproximately 15.0 m within the Raglan Marl Group a groundwater flow direction to the south,south-east with a more prominent flow direction to the south-east in the southern portion ofthe site was inferred. Using the groundwater elevations from the deeper installations a flowdirection to the east south-east was inferred. The deeper groundwater had a more easterlycomponent of flow than the shallower deposits. The groundwater in the Raglan Marl Group islikely to be directly in continuity with the Afon Lwyd.

It was concluded that the groundwater in the Alluvium is partially confined by the overlyingclayey deposits and groundwater typically rises in comparison to its strike level. This was notthe same on the adjacent playing fields that did not have consistent overlying clayey alluvialdeposits, which may have been eroded by the fluvial action. The groundwater in the Alluviumappears to be perched over a cohesive mudstone unit that was inferred to be theRaglan Marl Group.

In the Raglan Marl Group there were no obvious groundwater strikes, but resting water levelswere present in the overlying Alluvium at approximately 2.0 m – 3.0 mbgl. In comparableinstallations there was a vertical head difference of between 0.3 m and 0.97 m between theAlluvium and the Raglan Marl Group installed to medium depths (10 – 15 mbgl).

Within the Raglan Marl Group there was a distinct head difference between the 10 – 15 mdeep monitoring wells and the deeper 30 – 35 m deep wells. There was again a vertical headdifference within the Raglan Marl Group, which was most distinct in the east of the siteadjacent to the railway line with a head difference of 1.85 m. In all cases there was adownward vertical head difference within the Raglan Marl Group.

The measured groundwater elevations suggest that the water bodies may be directly inconnection with each other despite no obvious groundwater strikes noted within the mudstonedeposits. The groundwater may not be perceivable, but is present within the mudstone infissures and joints that mean there is no unsaturated zone in the Raglan Marl Group.

BoreholeSet Groundwater Elevation (mAOD)

ScreenedUnit BH411/ BH306 BH132/ BH301 BH204/ BH305 BH102/ BH303

Alluvium 49.77 52.59 50.46 51.51

Raglan Marl(15m)

49.46(-0.31)

52.04(-0.55)

49.49(-0.97)

51.09(-0.42)

Raglan Marl(30m)

49.03(-0.43)

51.67(-0.37)

49.03(-0.46)

49.24(-1.85)

NotesBased on groundwater elevation data from 29th April 2010Figures in parentheses are elevation differences (m) relative to the aquifer unit above

3.3.8 Hydrology

Inspection of the OS map for the area (Landranger 171, Cardiff and Newport, 1997) indicatesthe nearest surface water feature to the site is the Afon Lwyd, located 250 m to the east. Thewater quality of the river was classified by the EA as ‘C’, i.e. fair quality in 1998. Informationobtained from the EA website, accessed in November 2007, indicates that there has been a

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notable improvement in the river quality and between 2004 and 2006 the river was classifiedby the EA as ‘B’, i.e. good. Information obtained from Torfaen County Borough Councilindicates the Afon Lwyd river, meaning ‘grey river’ has reputedly the second highest rise andfall of the European rivers and in periods of heavy rainfall, the river quickly reaches itsmaximum within a short timescale.

The Cwmbran Brook is located 400 m to the west of the site and is culverted beneathCwmbran town centre, which discharges to the Afon Lwyd located to the south of the facility.

3.3.9 Flooding Risk

The EA’s ‘What’s In Your Backyard?’ search engine indicates that the Afon Lwyd is at risk offlooding in areas without defences. The site is indicated to be within an area of extremeflooding. Some river defences are present to the south-east of the site, along the Afon Lwyd.

3.3.10 Surface Water Abstractions

The Envirocheck® Report provides one record of an active licensed surface water abstractionlocated within a 2 km radius of the site. The abstraction is located approximately 986 msouth-west of the site from the Cwmbran Brook and is licensed to Torfaen County BoroughCouncil for intake to the boating lake.

3.3.11 Sensitive Land-Uses

The Countryside Council for Wales ‘Interactive Maps’ on-line facility, indicates that there are anumber of ecological receptors surrounding the site, as defined by Table A of Annex 3 of theDepartment for Environment, Food and Rural Affairs (DEFRA) Circular 01/2006‘Contaminated Land: Implementation of Part 2A of the Environmental Protection Act 1990’.The ecological receptors are summarised below:

Site Type Managed By National GridReference

Approx.Distance from

Site (Miles)Coed Meyric

MoelWildlife Trust

Centre ST 272 940 1.7 south-west

Henllys BogSite of Special

ScientificInterest (SSSI)

ST 263 926 2.6 south-west

Allt-yr-yn Local NatureReserve

Gwent WildlifeTrust

:ST 296 886 4.3 south

Craig Y Wenallt Woodland TrustCentre Woodland Trust ST 260 910 3.5 south-west

Dan-y-graig Wildlife TrustCentre

Gwent WildlifeTrust ST 234 903 4.9 south-west

3.4 Environmental Sensitivity

Due to the presence of the Secondary Aquifers beneath the site, the groundwater sensitivity isconsidered to be of medium sensitivity. The site is not located within a groundwater SPZ, andthere are no groundwater abstractions within a 2 km radius from the site. Receptor sensitivitywith respect to surface water features and sensitive land-uses is considered to be medium tohigh, given that the closest surface water feature is located 250 m from the site in anurbanised area. The nearest surface abstraction is located 986 m from the site and is notused for potable water supply.

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4 RELEVANT POLLUTANT LINKAGES

Several phases of environmental works have been performed at the Cwmbran facility. Theseworks have identified potentially unacceptable risks presented by the current environmentalcondition of the site for based on the proposed redevelopment for a commercial end-use.

The following exposure pathways are modelled as potentially active within the DQRA basedon the redevelopment of the site for a commercial end-use:

4.1 Future On-Site Commercial Worker

Inhalation of indoor air (soil and groundwater); Inhalation of indoor dust (soil); Inhalation of outdoor air (soil and groundwater); Inhalation of outdoor dust (soil); and, Incidental direct contact (soil).

4.2 Neighbouring Commercial Worker

Inhalation of indoor air (groundwater); and, Inhalation of outdoor air (groundwater).

4.3 Other Considered Scenarios

The area of land located adjacent to the south-east of the site is currently leased by Meritorand used as playing fields for the site personnel. ARCADIS has been informed that rugby/football training takes place approximately three times a week with matches being playedevery other week. A site-specific exposure scenario was developed for this activity based onthe commercial worker exposure data for 16-65 year-old female adults as defined by the EA.It was noted that the sports persons (represented by a rugby player) are also likely to beworking on-site during normal working hours.

In addition to the above it is likely that a groundsman/ maintenance worker will be required forthe upkeep of the playing fields. As such, a groundsman/ maintenance worker has also beenconsidered as a potential receptor, represented by a 16-65 year-old female adult.

It is also noted that the playing fields are often subject to trespass by local residents. As sucha consideration has also been given to this scenario with the following potential receptorsidentified:

dog walkers; and, youths/ teenagers.

It is considered appropriate to assess the most sensitive potential receptor for the off-siteplaying fields end-use. Hence the Site-Specific Assessment Criteria (SSAC) generated areprotective of the identified site users. Sensitivity analysis was undertaken based on the likelyexposure scenarios for each of the potential off-site playing field users. The results indicatedthat for the off-site playing fields, the teenager is the most sensitive of the receptors scenariosassessed. Therefore, the teenager receptor was considered further within the DQRA. Inaddition, given the potential for cumulative exposure via sources both on-site and during useof the playing field, the rugby player receptor was also assessed in the DQRA.

4.3.1 Off-Site Playing Fields Trespasser

Inhalation of outdoor air (soil and groundwater);

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Inhalation of outdoor dust (soil); and, Incidental direct contact (soil).

4.3.2 Off-Site Playing Fields

Inhalation of indoor air (soil and groundwater); Inhalation of indoor dust (soil); Inhalation of outdoor air (soil and groundwater); Inhalation of outdoor dust (soil); and, Incidental direct contact (soil).

4.4 Water Resource Receptors

‘Water Resource Receptors’ refers to controlled waters to which impact could potentiallyoccur. ‘Controlled Waters’, as detailed in s.104 of the Water Resources Act 1991, coverspractically all natural waters in England and Wales, and includes coastal waters, inland freshwaters and groundwater.

The following water resource receptors have been identified associated with the site and havebeen considered in this DQRA as the primary water resource receptors:

The Secondary (A) Aquifer beneath the site; and, Afon Lwyd located approximately 150 m to the south-east of the site.

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5 REMEDIATION STRATEGY

Some elements of the remediation works will be incorporated in the proposed redevelopmentworks being conducted on the site. However, it is considered likely that remediation works willcontinue in the southern extent of the site following the completion of the site redevelopmentpotentially for a number of years.

The site currently comprises an active heavy vehicle braking systems and axle productionplant, with a main production building, employees car park, visitors car park, redundanteffluent treatment plant, swarf house, electrical sub-stations and offices amongst other on-siteinfrastructure.

Inspection of the proposed site layout plan indicates that the redevelopment of the site willcomprise in the northern area of the site:

A supermarket with associated petrol filling station and smaller retail units; and, A pedestrian bridge from the site into the town centre.

It is understood that the northern employees’ car park is to be divested and redeveloped as asupermarket and petrol filling station. None of the measured concentrations of CoC in soiland/ or groundwater samples exceeded the derived Site-Specific Assessment Criteria (SSAC)based on the future redevelopment of the northern part of the site for the end-use, therefore ithas not been considered further in this report.

Inspection of the proposed site layout plan indicates that the redevelopment of the site willcomprise in the central area of the site:

Commercial offices; A hotel and associated bar/ restaurant; and, Car parking areas.

Inspection of the proposed site layout plan indicates that the redevelopment of the site willcomprise in the central area of the site:

A heavy vehicle braking systems production building, occupying a reduced footprint incomparison to the current site layout;

Employee and visitor car parking areas; A welcome centre; and, Meritor’s offices.

5.1 Remediation Objectives

The remediation objectives for the site are as follows:

To remove the potential historic primary sources of contamination on the site duringredevelopment work;

Reduce the concentrations of soil, soil gas and groundwater contaminants beneath thesite to concentrations that are no longer considered to present a risk to receptorsassociated with the site;

Reduce the thickness of LNAPL across the site, as it has the potential to act as anon-going source of CoC, partitioning into sorbed, dissolved and vapour phases;

Reduce DNAPL potentially identified in the south-east corner of the site; and, Restrict potential migration of identified on-site impacts to off-site receptors.

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5.2 Stakeholder Considerations

5.2.1 Site Owner

ARCADIS understands that Meritor intends to consider the sale of its freehold ownership ofthe northern approximate two thirds of the site, including a parking area to the north of themain factory building for a commercial end-use. Remediation technologies that may causedisruption to site operations or require infrastructure to be installed above ground can beconsidered as ARCADIS assumes that the remediation can be undertaken prior to the use ofthe majority of the site.

5.2.2 Regulators

Remediation must be acceptable to regulators and must not render the site unfit forredevelopment for commercial use.

5.2.3 Neighbouring Resident/ Property Owners

The site is located in close proximity to other commercial properties, this placesconsiderations on control of noise and prevention of vapour migration that may arise from theapplication of potential remediation technologies.

5.3 Remediation Approach

The site is currently an active braking system and axle production plant, but redevelopmentfor a future commercial end-use assumes on-site activities will cease in some areas and thatthe current underground and above-ground structures may be removed from site and accessto previously inaccessible areas may be possible to access. The remediation technologiesselected are considered to represent best available technology for the identified impacts andground conditions reported to be present beneath the site.

This section presents a brief review of the top remediation technologies which werehighlighted as the most likely to be technically, operationally and commercially feasible.

5.3.1 South-East Corner of Site & Southern Site Boundary

The majority of, and the most notable measured concentrations of, CoC in the soil andgroundwater exceeding the defined SSAC are located in the south-east corner of the site inthe vicinity of the former virgin TCE and virgin oil storage area. It is considered likely thathistorical spillages/ leaks of oils and TCE have entered the soil beneath the site. Anecdotalevidence indicates that spillages occurred during the filling of the TCE tank and whentransferring TCE from the AST to drums for transfer to degreasers located around the site.The measured concentrations of several CoC in the soil and groundwater samples collectedfrom this area potentially present a risk to human health receptors (current and future Meritorsite-staff) and the water resources associated with the site (Secondary Aquifer beneath thesite and the Afon Lwyd).

A notable thickness of LNAPL is also present on the groundwater in the monitoring wellslocated in the south-east corner of the site in the vicinity of the former virgin oil storage area. Itis considered likely that historical spillages/ leaks of oils have entered the soil beneath thesite. Free-phase product has also been encountered in the monitoring wells in the southernportion of the site and adjacent to the southern site boundary in the vicinity of the former boilerand compressor houses. It is considered likely that historical spillages/ leakages of oils on-sitehave entered the soil beneath the site. Spillages may also have occurred during filling of gasoil ASTs. which may have entered the ground via cracks in hardstanding. The Non-AqueousPhase Liquid (NAPL) has the potential to act as an on-going source of CoC, partitioning intosorbed, dissolved and vapour phases. Therefore, higher CoC concentrations may be present

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in the vicinity of the areas containing free-phase product. The LNAPL has been encounteredin monitoring wells beneath the southern half of the site, which in this form has the potential tobe volatile hence the risks via inhalation pathways cannot be discounted in areas containingfree-phase oil.

The following technologies have been identified as potentially suitable for managing the riskpresented to the receptors associated with this area of the site by managing or breaking thesource-pathway-receptor linkages:

Potential Technologies toAddress Impacts to SoilQuality

Soil Excavation; or,Soil Vapour Extraction (SVE).

Potential Technologies toAddress Impacts toGroundwater Quality

Soil Excavation (Source Removal);Total Fluids Pumping to Remove DNAPL (Source Removal);In Situ Chemical Oxidation;Hydraulic Containment/ Barrier;Air Sparging;Zero Valent Iron; or,Enhanced Reductive Dechlorination (ERD).Treatment of Extracted Groundwater by Air Stripping and/ orAdsorption;

Potential Technologies toRemove LNAPL

LNAPL Skimming; or,Total Fluids Pumping.

Potential Technologies toRemove DNAPL Total Fluids Pumping to Remove DNAPL

The preferred technologies are discussed in more detail below:

Source RemovalARCADIS considers that the first phase of remediation to be undertaken in the south-eastcorner of the site is source removal, comprising LNAPL removal, soil excavation andDNAPL pumping to remove the on-going source of impacts to groundwater quality in that areaof the site.

Excavation and Disposal of Impacted SoilARCADIS considers impacted soil excavation and disposal to be the most suitable initialtreatment option for the near surface soil impacts in the south-east corner of the site. This canbe undertaken in a pragmatic way to coincide with site redevelopment or improvement phasesor opportunities to access areas of the site.

AdvantagesThe benefits of impacted soil excavation and disposal are:

Soil excavation will address all of the CoC exceeding the derived SSAC in the shallowunsaturated soil in the south-east corner, both VOCs and Polynuclear AromaticHydrocarbons (PAHs).

Contaminant mass removal, close to 100 % removal so there is no chance of rebound. Excavation is generally considered to be a low-cost technology. Improvement to ground conditions can be achieved alongside contaminant removal (e.g.

stabilisation). Soil excavation should have a beneficial effect on the shallow groundwater at the site as

the source of on-going impact to groundwater quality will be removed.

LimitationsThe disadvantages of impacted soil excavation and disposal are:

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The proximity to the railway line will mean that permission from Network Rail will need tobe sought prior to commencing the works and that they may impose additional monitoringrequirements on the project, such as vibration monitoring. Alternatively they may restricthow close the excavation can progress towards the railway line.

Due to the shallow resting water table the excavation may require sheet piling. The distance from the contaminated site to the nearest appropriate landfill (most likely to

be hazardous) will affect cost. The number of landfills accepting hazardous waste islimited in the UK

Transportation of the soil through populated areas may affect community acceptability. Large-scale impacted soil excavation and disposal is not a sustainable solution.

It is anticipated that the timescale for the initial phase of soil treatment should be relativelyshort measured in terms of weeks or months.

LNAPL RemovalThe LNAPL has the potential to act as an on-going source of CoC, partitioning into sorbed,dissolved and vapour phases. ARCADIS considers total fluids pumping or LNAPL skimmingto be suitable initial treatment options for the shallow groundwater in the south-east corner ofthe site. Removing the LNAPL should have a beneficial effect on the groundwater at the siteas the source of on-going impact to groundwater quality will be removed. By undertakingproduct removal at the hydraulically down-gradient boundaries this will also act as acontaminant strategy to prevent off-site migration. It is also considered likely that LNAPLremoval will be the minimum remediation approach the Regulators will require at the site.This technique may also be able to utilise the neighbouring retaining wall that may be actingas a hanging barrier. Further assessment may be needed to confirm this.

Both techniques require specially designed extraction wells to be installed in the south-eastcorner of the site to target the interface between the LNAPL and resting groundwater. Fortotal fluids pumping top loading submersible pumps would be installed in the extraction wellnetwork. Using this technique impacted groundwater and LNAPL would be pumped from theextraction wells to above-ground treatment equipment or for disposal off-site. For productskimming auto-seeking devices, that automatically follow the elevation of the oil-waterinterface as it fluctuates, adjusting to fluctuations in the water table and/ or the recharge rateof the product in the well will be installed across the extraction well network. Extracted LNAPLwill be pumped above-ground for collection in a suitable vessel prior to disposal off-site.

AdvantagesThe benefits of total fluids pumping and product skimming are:

Contaminant mass removal. Total fluids pumping is generally considered to be a low-cost technology. LNAPL removal should have a beneficial effect on the shallow groundwater at the site as

the source of on-going impact to groundwater quality will be removed and subsequentgroundwater remediation timescales will be reduced.

Based on the flow direction and product thickness adequate product should be present inthe wells.

LimitationsThe disadvantages of total fluids pumping and product skimming are:

Pilot testing is often necessary to assess the suitability of extraction technologies. Extraction technologies require specialist equipment with regular monitoring by

competent persons to provide control during operation.

In addition, for total fluids pumping the extraction of groundwater and LNAPL requires anoil-water separator and the extracted groundwater will most likely require treatment prior todisposal.

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It is anticipated that the timescale for the initial phase of groundwater treatment should berelatively short usually 6 months to 2 years under optimal conditions.

DNAPL PumpingWhilst DNAPL has not been encountered in the monitoring wells in the south-east corner ofthe site, dissolved phase concentrations in the groundwater samples submitted for analysisindicate it is likely that DNAPL is present in the sub-surface. The MIP logs from the locationsprogressed in the south-east corner and in particular MIP036 to MIP039 and MIP075 suggestthat DNAPL maybe present at the interface between the Alluvium and the Raglan Marl Group.

ARCADIS considers DNAPL removal to be the most suitable initial treatment option for theshallow and deeper groundwater in the south-east corner of the site. Removing the DNAPLshould have a beneficial effect on the groundwater at the site as the source of on-goingimpact to groundwater quality will be removed. It will also enhance any groundwatertreatment that will subsequently occur by some rapid mass removal.

ARCADIS proposes that specially designed extraction wells are installed in the south-eastcorner of the site to target the interface between the Alluvium and the Raglan Marl Group andthat bottom loading submersible pumps are installed in the extraction well network. Using thistechnique impacted groundwater and DNAPL, if present, will be pumped from the extractionwells, above ground for treatment and disposal off-site (total fluids pumping).

AdvantagesThe benefits of DNAPL removal are:

Contaminant mass removal. Total fluids pumping is generally considered to be a low-cost technology. DNAPL removal should have a beneficial effect on the shallow groundwater at the site as

the source of on-going impact to groundwater quality will be removed and subsequentgroundwater remediation timescales will be reduced.

LimitationsThe disadvantages of DNAPL removal are:

Targeting DNAPL for removal can prove to be difficult and requires the extraction wells tobe carefully designed to screen the right zone.

Extraction of groundwater and LNAPL requires a NAPL-water separator. Extracted groundwater will most likely require treatment prior to disposal.

It is anticipated that the timescale for the initial phase of groundwater treatment should berelatively short, measured in terms of weeks or months.

Groundwater TreatmentFollowing the source removal works, ARCADIS considers that the following are potentiallysuitable techniques for addressing the impacts to groundwater quality:

Hydraulic Containment; Air Sparging; In Situ Chemical Oxidation (ISCO); and, Enhanced Reductive Dechlorination (ERD).

Of these options ERD or ISCO are considered to be the most suitable techniques formanaging the risks presented to human health and water resource receptors associated withthe site. The risks could be addressed through Monitored Natural Attenuation (MNA) orinstallation of an active or passive barrier but the use of barrier technologies or MNA wouldresult in a higher residual liability and longer term commitment to monitoring of theremediation strategy. Therefore ERD or ISCO are the preferred techniques.

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Enhanced Reductive DechlorinationERD involves the creation of a biological In situ Reactive Zone (IRZ) to enhance microbialdegradation of reduced organic compounds, such as chloroform and TCE. These chlorinatedcompounds are used by micro-organisms for respiration (as a terminal electron acceptor)when an adequate supply of a carbon source (electron-donor) is supplied and other moreenergetically favourable terminal electron acceptors are depleted. This remediation techniqueinvolves introduction of a biodegradable carbon source (such as molasses or corn syrup) tothe sub-surface to promote microbial degradation. This system may be combined with totalfluids pumping by amending and re-injecting groundwater. This re-circulating approach wouldinvolve complex design phases but may speed up the process.

AdvantagesThe benefits of ERD are:

Microbial dechlorination has been proven effective for the remediation of chlorinatedhydrocarbon impacts.

The time required for remediation is relatively short.

LimitationsThe disadvantages of ERD are:

The technology can be used but may be less effective against selected halogenatedVOCs.

Tracer tests are required prior to the introduction of a biodegradable carbon source. Specifically designed injection wells are required for the introduction of a biodegradable

carbon source.

This technique offers the advantage that contaminant destruction. The on-going liability islikely to be mitigated in a relatively short time period (2 – 5 years).

In Situ Chemical OxidationIn situ chemical oxidation would involve mixing of chemical oxidants in solution into the soiland groundwater beneath the site to destroy the contaminants.

AdvantagesThe benefits of chemical oxidation include:

The greatest advantages of ISCO are the rapid treatment time and the ability to treatcontaminants present at high concentrations.

LimitationsThe disadvantages of chemical oxidation include:

ISCO is non-selective. As such, the oxidant will not only react with the targetcontaminants, but also with natural substances in the soil that can be readily oxidised.Therefore treatability studies would be required prior to adding the oxidants.

Capital costs are typically high. Operating costs can also be high There is a requirement for handling large quantities of hazardous oxidising chemicals on-

site due to the oxidant demand of the target organic chemicals Consideration also must be given to the effects of oxidation on the sub-surface and the

possible formation of toxic by-products; evolution of heat and gas; and biologicalperturbation.

This approach is an aggressive technique, which is likely to achieve treatment of the soils to alevel beyond the site target levels in a short timeframe (i.e. < 2years), hence the residualliability following the treatment period would be expected to be negligible.

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5.3.2 South-Western Corner and Central & Southern Areas of Main ProductionBuilding and the Southern End of East Road

During the redevelopment ARCADIS assumes that on-site above and below groundstructures will be decommissioned and removed from site. Therefore technologies differentfrom those identified as suitable should the site continue its current use have been identifiedas suitable for addressing impacts to soil and groundwater in this area of the site by managingor breaking the source-pathway-receptor linkages:

Potential Technologies toAddress Impacts to SoilQuality

Soil Excavation; or,SVE.

Potential Technologies toAddress Impacts toGroundwater Quality

In Situ Chemical Oxidation;Groundwater Pumping & Above Ground TreatmentAir Sparging;Zero Valent Iron; or,ERD.Treatment of Extracted Groundwater by Air Stripping and/ orAdsorption;

The preferred technologies are discussed in more detail below:

Soil TreatmentARCADIS considers impacted soil excavation and disposal to be the most suitable treatmentoption for the near surface soil impacts across the site.

AdvantagesThe benefits of impacted soil excavation and disposal are:

Soil excavation will address all of the CoC exceeding the derived SSAC in the shallowunsaturated soil in the south-east corner, both VOCs and PAHs.

Contaminant mass removal, close to 100 % removal so there is very limited chance ofrebound.

Excavation is generally considered to be a low-cost technology. Improvement to ground conditions can be achieved alongside contaminant removal (e.g.

stabilisation). Soil excavation should have a beneficial effect on the shallow groundwater at the site as

the source of on-going impact to groundwater quality will be removed.

LimitationsThe disadvantages of impacted soil excavation and disposal are:

Due to the shallow resting water table the excavation may require sheet piling. The distance from the contaminated site to the nearest appropriate landfill (most likely to

be hazardous) will affect cost. The number of landfills accepting hazardous waste islimited in the UK

Transportation of the soil through populated areas may affect community acceptability. Impacted soil excavation and disposal is not a sustainable solution.

It is anticipated that the timescale for the initial phase of soil treatment should be relativelyshort measured in terms of weeks or months

LNAPL RemovalThe LNAPL has the potential to act as an on-going source of CoC, partitioning into sorbed,dissolved and vapour phases. ARCADIS considers total fluids pumping or LNAPL skimmingto be suitable initial treatment options for the shallow groundwater across the site. Removingthe LNAPL should have a beneficial effect on the groundwater at the site as the source of on-

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going impact to groundwater quality will be removed. It is also considered likely that LNAPLremoval will be the minimum remediation approach the Regulators will require at the site.

Both techniques require specially designed extraction wells to be installed across site totarget the interface between the LNAPL and resting groundwater. For total fluids pumping toploading submersible pumps would be installed in the extraction well network. Using thistechnique impacted groundwater and LNAPL would be pumped from the extraction wells,above ground for treatment and disposal off-site. For product skimming auto-seeking devices,that automatically follow the elevation of the oil-water interface as it fluctuates, adjusting tofluctuations in the water table and/ or the recharge rate of the product in the well will beinstalled across the extraction well network. Extracted LNAPL will be pumped above groundcollected in a suitable vessel prior to disposal off-site.

AdvantagesThe benefits of total fluids pumping and product skimming are:

Contaminant mass removal. Total fluids pumping is generally considered to be a low-cost technology. LNAPL removal should have a beneficial effect on the shallow groundwater at the site as

the source of on-going impact to groundwater quality will be removed and subsequentgroundwater remediation timescales will be reduced.

LimitationsThe disadvantages of total fluids pumping and product skimming are:

Pilot testing is often necessary to assess the suitability of extraction technologies. Extraction technologies require specialist equipment with regular monitoring by

competent persons to provide control during operation.

In addition, for total fluids pumping the extraction of groundwater and LNAPL requires anoil-water separator and the extracted groundwater will most likely require treatment prior todisposal.

It is anticipated that the timescale for the initial phase of groundwater treatment should berelatively usually 6 months to 2 years under optimal conditions.

Groundwater TreatmentARCADIS considers ERD or ISCO to be appropriate groundwater treatments for across thesite as discussed for the south-east corner of the site.

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6 SCOPE OF WORKS

6.1 Project Team

It is considered that the overall project team will comprise the following components:

Delivery Team Peer Review(ARCADIS) Meritor Regulators

Project Director

Project Manager

Dedicated Field Staff

Appointed Sub-Contractors

Global AccountTeam

Technical Specialists

Health and SafetyOfficer

Purchasing OfficerQuality Manager

Vice President -Environment, Safety& Facility Services

EnvironmentalHealth Officers for

Torfaen CountyBorough Council

Technical OfficerGroundwater and

Contaminated LandTeam for the

Environment Agency

6.2 Remediation Phasing

It is anticipated that the remediation will be undertaken in a number of distinct phases asfollows:

Task 1: Regulatory Interface;Task 2: LNAPL and Impacted Groundwater Containment Pilot Testing – Southern Extent of

SiteTask 3: Baseline Groundwater Monitoring – Southern Extent of SiteTask 4: Completion of Remediation Method Statements and Remediation Implementation

Plan (RIP)Task 5: Implementation of a Full-Scale LNAPL and Impacted Groundwater Containment

Remediation System – Southern Extent of SiteTask 6: System Mobilisation and Commissioning – Southern Extent of SiteTask 7: System Operation, Monitoring and Maintenance – Southern Extent of SiteTask 8: Groundwater Treatment via ERD Pilot Testing – Central Area of SiteTask 9: Baseline Groundwater Monitoring – Full Extent of SiteTask 10: Implementation of a Full-Scale Groundwater Treatment Infrastructure – Central and

Southern Areas of the SiteTask 11: System Mobilisation – Central and Southern Areas of the SiteTask 12: System Operation, Monitoring and Maintenance – Central and Southern Areas of

the SiteTask 13: Investigation of Previously Inaccessible Areas of the Site – Central and Southern

Areas of the SiteTask 14: Delineation and Remediation of Unexpected Impacts to Soil and Groundwater

Quality Identified inn Previously Inaccessible Areas of the Site – Central andSouthern Areas of the Site

Task 15: Post-Remediation Groundwater Monitoring; and,Task 16: Remediation Closure and Reporting.

A proposed remediation timetable is presented on Figure 3.

Tasks 5 to 7 are designed to provide hydraulic containment at the hydraulically down-gradientsite boundary and to restrict the migration of identified on-site impacts to off-site receptors aswell as reducing the thickness of LNAPL across the southern extent of the site, as it has thepotential to act as an on-going source of CoC, partitioning into sorbed, dissolved and vapour

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phases. Based on the concentrations of TCE and its associated breakdown products in thegroundwater in the south-east corner of the site, it is possible that DNAPL is trapped in thesub-surface. Tasks 3 to 7 have also been designed to address and reduce the DNAPLthickness potentially located in the south-east corner of the site.

Tasks 8 to 12 have been designed to reduce the concentrations of soil, soil gas andgroundwater contaminants beneath the site to concentrations that are no longer considered topresent a risk to receptors associated with the site.

Tasks 13 and 14 are designed to address potential previously unknown historic primarysources of contamination on the site during redevelopment work. The redevelopment andimprovement of the Meritor production facility will be a medium to long-term engineeringproject so a pragmatic approach to removal of shallow soil sources for example will beundertaken as and when areas become available. The lack of risk posed by the free-phase oilmeans in the event that the oil is contained on-site and proven to be static or reducing,proposals will be made to remediate over a longer term.

6.3 Task 1: Regulatory Interface

The programme assumes a two to three month period of planning and regulatory liaison.However, the lead in period for planning and regulatory liaison will be subject to theresponses received.

The following issues should be addressed during this period:

Remediation licensing; Application of a discharge consent; and, Installation of electricity supply to the site (if needed).

Some of the subsequent tasks can be conducted within this period to reduce the overallduration of the remediation programme.

The details of the pilot testing and remediation approach will be sent to Regulators. This willenable agreement to be sought regarding the proposed scheme in principle regardingresolution of licensing requirements whilst preliminary tasks (such as baseline groundwatermonitoring) are being undertaken. Regulatory feedback, where appropriate, will beincorporated into the pilot testing design.

6.3.1 Abstraction Licences and Discharge Consents

A groundwater abstraction licence may be required from the EA in order to operate thecontainment system in the southern extent of the site. Based on the results of the pilot testing(Task 2) the optimum abstraction rate will be determined. An abstraction licence should not berequired where abstraction rates are below 20 m3 per day.

A discharge consent is likely to be required to discharge treated effluent to sewer during theremediation works. However, Meritor already holds a consent for discharge via the redundanteffluent treatment works. ARCADIS proposes that the details of effluent treatment should bediscussed with the sewerage undertaker and if necessary request an amendment to thecurrent discharge consent. The remediation equipment design may be amended asnecessary in order to achieve any consented conditions.

No treated effluent will be discharged via the SWDS to the Afon Lwyd.

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6.3.2 Waste Management Licensing

The requirement to perform in situ remediation at the site under an Environmental Permit hasbeen assessed.In the event that the volume of treated media is beneath the 1,000 m3 threshold, remediationactivities can be undertaken without an Environmental Permit as detailed in the EA Licensing/Permitting Position Statements, Licensing/ Permitting Position 1.1 – Trials and small scaleremediation schemes:

“Where a small scale remediation scheme or a trial is to be undertaken to determine whetheror not a particular remediation technique is suitable to ensure the remediation ofcontaminated materials, then provided that:

(1) for any site the total quantity of contaminated material, substances or products treated aspart of the trial remediation project does not exceed 1000 m3, and

(2) the name, contact address (home or business), and contact telephone numbers of anylandowner, developer or contractor involved in the remediation project, details of thetechnique and dates on site, are supplied to the Environment Agency area office at least fiveworking days before that project begins, then the Environment Agency will not expect a wastemanagement license to be obtained to cover these works.”

However, based on the current understanding of the site, ARCADIS anticipates that thetreatment volume will be greater than the 1,000 m3 threshold, and therefore anEnvironmental Permit will be required for the full-scale remediation works at the site.

6.4 Task 2: LNAPL and Impacted Groundwater Containment Pilot Testing – SouthernExtent of Site

The objective of the remediation pilot testing is to assess the response of the sub-surface tothe remediation technique. The pilot testing will assess the feasibility of the remediationtechnique and will also provide sufficient information to allow for the technical developmentand budget costing of a full-scale remediation system.

Currently ARCADIS considers that pilot testing of the following remediation techniques isappropriate for the southern extent site:

Permeability Testing (Groundwater Pumping); and, Dual Phase Extraction/ Vacuum Enhanced Recovery.

The LNAPL and impacted groundwater containment pilot testing should include the followingtasks:

1. Installation of pilot testing infrastructure;2. Mobilisation of pilot testing systems to site;3. Multiple tests for each proposed aspect of the potential remediation technique; and,4. Reporting of findings.

6.5 Task 3: Baseline Groundwater Monitoring – Southern Extent of Site

In order to provide a baseline to measure the performance of the remediation system from, agroundwater monitoring visit is proposed comprising:

The inspection of on-site monitoring wells in the southern extent of the site for thepresence of groundwater and free-phase hydrocarbon product;

The use of an oil-water interface probe for measurement of depths to groundwater and

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thickness of free-phase hydrocarbon product, if present; and, Groundwater sampling.

Groundwater samples should be collected from the monitoring well network across the site,where free-phase hydrocarbon product is not present, for subsequent laboratory analysis.Groundwater samples will be submitted for laboratory analysis for:

Total Petroleum Hydrocarbons Criteria Working Group (TPHCWG) via GasChromatography - Flame Ionisation Detector (GC-FID) methods;

Benzene, toluene, ethylbenzene and total xylenes (BTEX compounds) via GasChromatography - Mass Spectroscopy (GC-MS) methods; and,

Methyl tertiary-butyl ether (MTBE) via GC-MS methods.

The following hydrogeochemical parameters will also be recorded at the well-head during thegroundwater sampling:

Dissolved Oxygen Concentrations; pH; Electrical Conductivity; and, Oxidation-reduction Potential.

6.6 Task 4: Remediation Method Statements & Remediation Implementation Plan

The technical data from the results of the pilot testing will be fully assessed and its findings orimplications used in full-scale design of the remediation system to be installed. This designwill be incorporated in a remediation implementation plan (RIP) in line with regulatoryguidance. The RIP and associated remediation method statements will be sent to Regulatorsfor comment, which is likely to be required by any planning conditions for the site. This willenable agreement to be sought regarding the proposed scheme in principle regardingfinalisation of licensing requirements. Regulatory feedback will be incorporated into changesof the full-scale design and the RIP.

At the RIP stage realistic and achievable Remediation Criteria (RC) will be proposed to andnegotiated with the Regulators. The RC will be proposed based on the risk-based targetsderived in the DQRA as well as taking into account commercial, technical feasibility and cost-benefit considerations. The IP will form the basis of meeting any planning conditions imposedon the development.

At the conclusion of the negotiations the full-scale remediation design will be finalised and thetechnical development and budget costing will be complete. The implementation of the fullscale system will be possible as outlined in the tasks below. The RIP process is iterative andwill require revision for any subsequent or additional remediation works proposed or aftercompletion of future pilot testing.

6.7 Task 5: Implementation of a Full-Scale LNAPL and Impacted Groundwater ContainmentRemediation System – Southern Extent of Site

Following the remediation pilot testing phase and confirmation of the final remediation systemdesign, any additionally required extraction wells will be installed across the southern extentof the site. The provisional remediation system layout is presented on Figure 4 and shows theanticipated locations of the extraction wells. At present extraction wells spacing isapproximate 10 m grid spacing. are anticipated

The results of Task 2, will determine the optimum pipework layout connecting the extractionwells to the remediation system container. Currently it is assumed that the pipework will beinstalled as a mixture of above and below ground ground. Therefore for below groundpipework the following tasks will be undertaken:

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Health and safety preparation and utility clearance at each of the proposed investigationlocations where a service trace plan is not available.

Installation sub-surface ducting between the extraction wells and the remediationcompound in shallow sub-surface trenches.

Installation of inspection chamber covers over the existing extraction wells.

The extraction wells are to be located beneath inspection chambers, the specification of whichare presented below:

Minimum Depth: 750 mm Minimum Length: 600 mm Minimum Width: 450mm Manhole Cover: Steel flush to site surface Manhole Cover Rating: Heavy Traffic Rated

The nature of the works means that the Construction, Design and Management (CDM)Regulations, (2007) would apply to the excavation works. However, ARCADIS does notanticipate that this project will be notifiable unless within a wider site redevelopmentprogramme.

6.8 Task 6: System Mobilisation and Commissioning – Southern Extent of Site

Delivery of the remediation system to site is most likely to be via lorry mounted crane toenable the remediation container to be positioned in the location indicated on Figure 4.

Proposed mobilisation and commissioning tasks include:

Delivery of the remediation container to site; Delivery of effluent treatment system including oil-water separators and air stripping

system equipment; Delivery of absorbent media (GAC) to the site for treatment of extracted soil vapour and

groundwater and connection; Connection of the above-ground pipework to the remediation system, housed in the

remediation container; Power connection; Sewer connection; Initial system adjustments; and, Safety checks.

On commissioning, data will be collected to assess the initial operating parameters of thesystem and enable adjustment of the initial configuration. These checks may include some orall of the following:

Depth to groundwater across the treatment area; Groundwater Extraction Rates; and, Quality of extracted groundwater post treatment.

The system Operation and Maintenance (O&M) manual will be issued after the systemcommissioning. The O&M manual will include information on the following aspects:

System Overview; Process and Instrument Drawings; Operation and Maintenance Instructions; and, Monitoring Schedules and Data Logs.

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6.9 Task 7: System Operation, Monitoring and Maintenance – Southern Extent of Site

During the period of in situ remediation, the system would be operated automatically via anintegrated control panel. It is proposed to monitor the system monthly in order to track theoperation of the system and conduct maintenance tasks. It is anticipated that the systemoperational period will be 18 – 24 months, provided significant residual source does notremain beneath the site.

The plant operating, monitoring and maintenance schedule is designed to meet three keyrequirements for the operation of the remediation system.

1) To provide data for the tracking of system performance and progress towards theremediation objectives, and allow necessary adjustments to be made to optimise theremediation system;

2) To ensure reliable operation of the remediation system to minimise downtime, andensure clean-up goals are achieved as swiftly as possible; and,

3) To meet regulatory requirements for the waste discharge streams.

The system monitoring and maintenance tasks will comprise visual inspection and systemoperation optimisation as well as the collection of some or all of the following data:

Monthly

Measurement of depth to groundwater and free-phase hydrocarbon product, if present, inselected monitoring wells;

Power consumption; Water volume discharge measurements; Post-treatment groundwater treatment monitoring (both air stripper and adsorption); and, Post-treatment groundwater analysis of discharge samples based on the requirements of

the local sewerage provider.

Quarterly

Monthly tasks; and, Groundwater sampling from selected monitoring wells in order to confirm trends in

dissolved phase concentrations and evaluate the system performance at the site.

Groundwater samples should be collected from the monitoring well network in the southernextent of the site and off-site on the adjacent playing fields, where free-phase hydrocarbonproduct is not present, for subsequent laboratory analysis. Groundwater samples will besubmitted for laboratory analysis for:

Total Petroleum Hydrocarbons Criteria Working Group (TPHCWG) via GC-FID methods; Benzene, Toulene, Ethylbenzene and Xylenes (BTEX) compounds via GC-MS methods;

and, Methyl Tertiary-Butyl Ether (MTBE) via GC-MS methods.

The following hydrogeochemical parameters will also be recorded at the well-head during thegroundwater sampling:

Dissolved Oxygen Concentrations; pH; Electrical Conductivity; and, Oxidation-Reduction Potential.

Groundwater laboratory analysis data should be used to confirm the effectiveness ofremediation.

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6.10 Task 8: Groundwater Treatment via ERD Pilot Testing – Central Area of Site

The pilot trial proposed by ARCADIS will demonstrate the effectiveness of an enhancedreductive dechlorination (approach using carbohydrate reagent injections), while alsocollecting field-scale design data that can be used in a full-scale approach. The ERD pilot willtarget shallow groundwater containing the main CoC for the site which comprise chlorinatedvolatile organic compounds (cVOCs) including TCE, cis-1,2-DCE and vinyl chloride. A sourcearea in the centre of the site is proposed as the location of the pilot test, and as such thereshould be considerable mass removal benefits.

The ERD pilot test proposes batch injections of carbohydrates at discretely screened intervalsof the Alluvium and underlying Raglan Marl Group. Injections will proceed at varying intervals,with natural groundwater flux serving as the primary means of distributing the carbohydrateshydraulically down-gradient into a monitoring area. A short ERD programme is proposed, butthe overall scope could be extended if lag times for microbial proliferation and/ or lowergroundwater velocities require extension of the pilot trial. Given the evolved nature ofmicrobiology already expected at this site, extensive lag times are not suspected. Amonitoring programme is also proposed to assess the spreading of reagents within the IRZ,as well as collecting proof of process data to demonstrate the success of the technique inreducing cVOC concentrations. Trial for reinjection may also be considered using clean waterto assess the potential for recirculation system, which would minimise wastewater disposal.

6.11 Task 9: Baseline Groundwater Monitoring – Full Extent of Site

In order to provide a baseline to measure the performance of the remediation system from, agroundwater monitoring visit is proposed comprising:

The inspection of on-site monitoring wells across the site for the presence ofgroundwater and free-phase hydrocarbon product;

The use of an oil-water interface probe for measurement of depths to groundwater andthickness of free-phase hydrocarbon product, if present; and,

Groundwater sampling.

Groundwater samples should be collected from the monitoring well network across the site,where free-phase hydrocarbon product is not present, for subsequent laboratory analysis.Groundwater samples will be submitted for laboratory analysis for:

TPHCWG via GC-FID methods; BTEX compounds via GC-MS methods; MTBE via GC-MS methods; VOC via GC-MS methods; and, Total Organic Carbon via combustion methods.

In addition, selected groundwater samples were submitted for analysis for biogeochemicalindicator parameters:

Nitrate via Ion Chromatography (IC) methods; Nitrite via IC methods; Sulphate via IC methods; Sulphide via spectrophotometric methods; Dissolved Iron via ICP-MS methods; Dissolved Carbon Dioxide via infrared detection methods; and, Dissolved Methane via GC-FID methods

The following hydrogeochemical parameters will also be recorded at the well-head during thegroundwater sampling:

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Dissolved Oxygen Concentrations; pH; Electrical Conductivity; and, Oxidation-Reduction Potential.

6.12 Task 10: Implementation of a Full-Scale Groundwater Treatment Infrastructure –Central and Southern Areas of the Site

After an iteration of Task 4 with a revised or additional RIP the full-scale implementation willbe possible. Following the remediation pilot testing phase and confirmation of the finalremediation system design, any additionally required injection or monitoring wells will beinstalled across the central and southern areas of the site.

It is considered likely that additional injection and monitoring wells will be installed across thecentral area of the site, in the southern area of the site and in the south-east corner of the site,where the most notable concentrations of cVOCs have been measured in the soil andgroundwater. A decision will be made as to whether existing wells have remaining free-phaseproduct and could be utilised for this phase of remediation.

6.13 Task 11: System Mobilisation – Central and Southern Areas of the Site

Delivery of the components required for the remediation of the central and southern areas ofthe site, is most likely to be via lorry mounted crane to enable the remediation container to bepositioned in the location indicated on Figure 4, within a remediation compound.

The system O&M manual, including health and safety documentation such as safey methodstatements will be issued after the system commissioning. The O&M manual will includeinformation on the following aspects:

System Overview; Process and Instrument Drawings; Operation and Maintenance Instructions; and, Monitoring Schedules and Data Logs.

6.14 Task 12: System Operation, Monitoring and Maintenance – Central and Southern Areasof the Site

1st Injection and Tracer Test of CarbohydrateGiven the range of hydraulic conductivity (K) values obtained from the rising head tests (slugtests) completed by ARCADIS on the site and adjacent playing fields, and the assumedheterogeneity water bodies beneath the site, the injection-tracer test will allow for identificationof more discrete aquifer parameters that can be used to design an injection programme thatadequately distributes the carbohydrate solution across the central and southern areas of thesite.

The injection test will be accomplished by installing conductance probes in the monitoring wellnetwork and collecting conductance measurements of groundwater for several weeksfollowing the initial carbohydrate injection. Groundwater containing carbohydrate has elevatedtotal dissolved solids and other ions that make it a good conductance tracer target. Thebreakthrough “peak” observed in the data collected from the monitoring well network can beused to calculate the migratory porosity (i.e. connected effective porosity) for the Alluvialwater body and Raglan Marl Group aquifer.

Injection ProcedureA batch injection system is proposed for the Cwmbran site, which will utilise an inject and driftapproach. Carbohydrate reagent and water will be mixed to obtain a carbohydrate solution

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which will be injected from appropriate containers. The injections are likely to utilise lowpressures, so as not to affect geotechnical stability of the ground, but the exact methodologywill be established after the completion of Task 8.

Initial Injection Event TimescaleGiven the time taken for set-up of pumping equipment at each location and preparation ofreagent it is anticipated that the initial injection event will be achieved in a period of 5 workingdays.

Repeat InjectionsThe repeat injection events will be performed at intervals defined by the results of Task 7,which may vary between weekly and monthly cycles. These injections will be applied to thepermanent injection wells installed during Task 9.

6.15 Task 13: Investigation of Previously Inaccessible Areas of the Site– Central andSouthern Areas of the Site

The site is currently an active braking system and axle production plant, howeverredevelopment for a future commercial end-use assumes on-site activities will cease in someareas of the site and that the current underground and above-ground structures may beremoved from site. Therefore access to previously inaccessible areas may become possible.

For areas where it is likely that impact to soil and or groundwater quality has occurred, suchas beneath the swarf house or effluent treatment park, ARCADIS recommends that furtherintrusive investigation is undertaken. The further on-site intrusive investigation task willcomprise the following:

Additional Laser Induced Fluorescence (LIF) and or Membrane Interface Probe (MIP)investigation

Installation of additional shallow boreholes targeting the interface between the Alluviumand the Raglan Marl Group.

Development and sampling of the newly installed monitoring wells.

In order to investigate the areas of the site previously inaccessible, rapidly and to make site-based decisions about the delineation of suspected free-phase product and/ or dissolved-phase plumes, ARCADIS recommends a combination of the use of LIF and MIP systems,which provides interactive data on product and solvent distribution and chemistry,respectively, plus the installation of selected conventional verification monitoring wells.

The investigation should adopt a targeted approach, focusing on areas of the site which werepreviously inaccessible and where is likely that impact to soil and or groundwater quality hasoccurred, such as beneath the swarf house or effluent treatment park.

Following investigation using the LIF and or MIP systems, ARCADIS recommends furtherboreholes are advanced across in the previously inaccessible areas of the site, to act asverification points. The monitoring wells installed within the boreholes should facilitate furtherLNAPL thickness monitoring, if present, and groundwater sampling. The boreholes should beadvanced to a target depth of 6.0 m – 7.0 mbgl, allowing soil samples to be collected and soilhorizons to be logged. Monitoring wells should be installed within the borehole locations toallow for subsequent groundwater sampling. Soil samples should be submitted for analysis ata Monitoring Certification Scheme (MCertS) accredited laboratory for analysis for the CoCidentified in the recently completed Phase IIA and IIB ESAs. The newly installed monitoringwells should be levelled into those monitoring wells installed during the previous Phase IIAand Phase IIB ESA to allow for groundwater flow direction to be inferred from the new andexisting monitoring wells. Subsequent to their installation monitoring wells should bedeveloped using a surge block to disturb sediment that may have collected in the monitoringwell and once agitated a submersible pump or inertial tubing should be lowered into the welland the water pumped until the development water was substantially clear of suspended

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solids. Following development the newly installed monitoring wells should be left to stabilisefor a minimum of one week after the additional intrusive investigation. After one week, thedepth to resting groundwater and LNAPL thickness (if present) will be measured in theexisting and newly installed wells prior to collecting groundwater samples. High levels ofdissolved hydrocarbons may be erroneously identified in groundwater, caused by particulatesin the sample or by a product sheen, which is strongly influenced by the samplingmethodology. It is therefore proposed that where possible low-flow sampling is used to collectgroundwater samples. Groundwater samples should be submitted for analysis at a UntiedKingdom Accreditation Service (UKAS) accredited laboratory for analysis for the CoCidentified in the recently completed Phase IIA and IIB ESAs.

6.16 Task 14: Delineation and Remediation of Unexpected Impacts to Soil and GroundwaterQuality Identified inn Previously Inaccessible Areas of the Site– Central and SouthernAreas of the Site

In the event that unexpected soil or groundwater impacts are identified this will be notified inwriting to the Regulators, as is likely to be required under any planning condition. If required,revised Remediation Method Statements will be prepared and agreed with the Regulators.

ARCADIS considers impacted soil excavation and disposal to be the most suitable initialtreatment option for the near surface soil impacts in areas previously not investigated at thesite due to restricted access, where potential impacts to soil and groundwater quality wereidentified in Task 13. This can be undertaken in a pragmatic way to coincide with siteredevelopment or improvement phases or opportunities to access areas of the site.

If significant impacts to groundwater quality are identified in the previously inaccessible areasof the site, the ERD groundwater treatment infrastructure may be extended to incorporatethese areas, if appropriate.

6.17 Task 15: Post-Remediation Groundwater Monitoring

It is proposed that the full-scale remediation systems should be switched off after themonitoring visits show that the remediation objectives have been met.

Compliance Monitoring/ Long Term Groundwater MonitoringOn obtaining the remediation objectives the monitoring wells on-site should continue to bemonitored at monthly intervals for a period of three to six months to determine whether siteconditions remain stable. Compliance groundwater monitoring will comprise:

The inspection of on-site monitoring wells across the site for the presence ofgroundwater and free-phase hydrocarbon product;

The use of an oil-water interface probe for measurement of depths to groundwater andthickness of free-phase hydrocarbon product, if present; and,

Groundwater sampling.

Groundwater samples should be collected from the monitoring well network across the site,where free-phase hydrocarbon product is not present, for subsequent laboratory analysis.Groundwater samples will be submitted for laboratory analysis for:

TPHCWG via GC-FID methods; BTEX compounds via GC-MS methods; MTBE via GC-MS methods; and, VOC via GC-MS methods.

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6.18 Task 16: Remediation Closure

Once the remediation targets have been achieved and the post-remediation compliancemonitoring completed, the results will be reported and forwarded to the Regulators.ARCADIS will aim to discharge the planning conditions at this stage. As an example the taregtof removal of impacts at site boundary to mitigate risk to water resources may be proposed,negotiated and used as the RC. In this event the planning condition can be satisfied withoutremoving all sources on-site. For this reason after operation of the containment systemceases voluntary remediation may continue on a longer term basis for various corporate,liability and commercial reasons. This may comprise enhanced microbial processes ornatural attenuation, which although not within planning would still be regulated. At finalisationof work and satisfaction of planning conditions by suitable rebound monitoring the remediationsystem should be decommissioned and remediation equipment, electricity and system controlunits removed from site. It is proposed that monitoring and extraction wells on the site will becapped and left in situ for future use.

On completion of the works required under planning, a validation report will be preparedwhich will include details of sampling locations, description of and laboratory analysis resultsof soil and groundwater samples taken during the works. The report will present the resultsobtained and will provide recommendations for either additional works if required dependingon the observed contaminant trends.

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7 SUMMARY

ARCADIS was commissioned by Meritor to prepare a RMS for the redevelopment of theirfacility in Cwmbran. The RMS was conducted at the request of Meritor, who it is understood isdivesting the northern two thirds of the freehold ownership of the site, including a parking areato the north of the main production building, for redevelopment for future commercial use.

ARCADIS has undertaken a number of previous phases of work. The conclusions of whichwere that further works would be required in order to appropriately manage the potential riskspresented to human health and water resource receptors, such that the site would be suitablefor commercial redevelopment.

It is understood that the current employees’ car park is to be divested and redeveloped as asupermarket and petrol filling station. This area of the site has not been considered further inthis report, as none of the measured concentrations of CoC in soil and/ or groundwatersamples exceeded the derived SSAC.

The ROA undertaken previously identified source removal and ERD as potentially appropriateremediation techniques for addressing the impacts to soil and groundwater quality beneaththe central and southern areas of the site. Some elements of the remediation works will beincorporated in the proposed redevelopment works being conducted on the site. However, it isconsidered likely that remediation works will continue in the southern extent of the sitefollowing the completion of the site redevelopment potentially for a number of years.

The following tasks will be undertaken during the remediation works:

Task 1: Regulatory Interface;Task 2: LNAPL and Impacted Groundwater Containment Pilot Testing – Southern Extent of

SiteTask 3: Baseline Groundwater Monitoring – Southern Extent of SiteTask 4: Completion of Remediation Method Statements and Remediation Implementation

Plan (RIP)Task 5: Implementation of a Full-Scale LNAPL and Impacted Groundwater Containment

Remediation System – Southern Extent of SiteTask 6: System Mobilisation and Commissioning – Southern Extent of SiteTask 7: System Operation, Monitoring and Maintenance – Southern Extent of SiteTask 8: Groundwater Treatment via ERD Pilot Testing – Central Area of SiteTask 9: Baseline Groundwater Monitoring – Full Extent of SiteTask 10: Implementation of a Full-Scale Groundwater Treatment Infrastructure – Central and

Southern Areas of the SiteTask 11: System Mobilisation – Central and Southern Areas of the SiteTask 12: System Operation, Monitoring and Maintenance – Central and Southern Areas of

the SiteTask 13: Investigation of Previously Inaccessible Areas of the Site – Central and Southern

Areas of the SiteTask 14: Delineation and Remediation of Unexpected Impacts to Soil and Groundwater

Quality Identified inn Previously Inaccessible Areas of the Site – Central andSouthern Areas of the Site

Task 15: Post-Remediation Groundwater Monitoring; and,Task 16: Remediation Closure and Reporting.

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8 STUDY LIMITATIONS

IMPORTANT. This section should be read before reliance is placed on any of the information,opinions, advice, recommendations or conclusions contained in this report.

1 This report has been prepared by ARCADIS(UK) Limited (ARCADIS), with all reasonableskill, care and diligence within the terms ofthe Appointment and with the resources andmanpower agreed with Meritor Heavy VehicleBraking Systems (UK) Limited andArvinMeritor Inc (the ‘Client’). ARCADISdoes not accept responsibility for any mattersoutside the agreed scope.

2 This report has been prepared for the solebenefit of the Client unless agreed otherwisein writing.

3 Unless stated otherwise, no consultationswith authorities or funders or other interestedthird parties have been carried out.ARCADIS are unable to give categoricalassurance that the findings will be acceptedby these third parties as such bodies mayhave unpublished, more stringent objectives.Further work may be required by theseparties.

4 All work carried out in preparing this reporthas used, and is based on, ARCADIS’professional knowledge and understanding ofcurrent relevant legislation. Changes inlegislation or regulatory guidance may causethe opinion or advice contained in this reportto become inappropriate or incorrect. Ingiving opinions and advice, pending changesin legislation, of which ARCADIS is aware,have been considered. Following delivery ofthe report, ARCADIS have no obligation toadvise the Client or any other party of suchchanges or their repercussions.

5 This report is only valid when used in itsentirety. Any information or advice includedin the report should not be relied upon untilconsidered in the context of the whole report.

6 Whilst this report and the opinions made arecorrect to the best of ARCADIS’ belief,ARCADIS cannot guarantee the accuracy orcompleteness of any information provided bythird parties.

7 This report has been prepared based on theinformation reasonably available during the

project programme. All information relevantto the scope may not have been received.

8 This report refers, within the limitationsstated, to the condition of the site at the timeof the inspections. No warranty is given as tothe possibility of changes in the condition ofthe site since the time of the investigation.

9 The content of this report represents theprofessional opinion of experiencedenvironmental consultants. ARCADIS doesnot provide specialist legal or otherprofessional advice. The advice of otherprofessionals may be required.

10 Where intrusive investigation techniqueshave been employed they have beendesigned to provide a reasonable level ofassurance on the conditions. Given thediscrete nature of sampling, no investigationtechnique is capable of identifying allconditions present in all areas. In some casesthe investigation is further limited by siteoperations, underground obstructions andabove ground structures. Unless otherwisestated, areas beyond the boundary of the sitehave not been investigated.

11 If below ground intrusive investigations havebeen conducted as part of the scope, servicetracing for safe location of exploratory holeshas been carried out. The location ofunderground services shown on any drawingin this report has been determined by visualobservations and electromagnetictechniques. No guarantee can be given thatall services have been identified. Additionalservices, structures or other below groundobstructions, not indicated on the drawing,may be present on site.

12 Unless otherwise stated the report providesno comment on the nature of buildingmaterials, operational integrity of the facilityor on any regulatory compliance issues.

13 Unless otherwise stated, samples from thesite (soil, groundwater, building fabric or othersamples) have NOT been analysed orassessed for waste classification purposes

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FIGU

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SITE LOCATION

LEGEND

REPRODUCED FROM OS 1:50,000 SCALE BY PERMISSION OF ORDNANCE SURVEY® ON BEHALF OF THE CONTROLLER OF HER MAJESTY'S STATIONERY OFFICE. © CROWN COPYRIGHT. ALL RIGHTS RESERVED. LICENCE NUMBER 100020449. CONTACT ARCADIS UK IN CASE ANY QUERY

Site Location

#NOTES

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Figure 3Proposed Remediation Schedule

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1 Regulatory Interface

2 LNAPL & Impacted Groundwater Containment Pilot Tetsing - SouthernExtent of Site

3 Baseline Groundwater Monitoring - Southern Extent of Site

4 Installation of Full-Scale LNAPL & Impacted Groundwater ContainmentRemediation System - Southern Extent of Site

5 System Mobilisation and Commissioning - Southern Extent of Site

6 System Operation, Monitoring and Maintenance - Southern Extent of Site

7 Groundwater Treatment via ERD Pilot Tetsing - Central Area of Site

8 Baseline Groundwater Monitoring - Full Extent of Site

9 Installation of Full-Scale Grundwater Treatment Infrastructure - Central andSouthern Areas of the Site

10 System Mobilisation - Central and Southern Areas of the Site

11 System Operation, Monitoringa and Maintenance - Central and SouthernAreas of the Site

12 Investigation of Previously Inaccessible Areas of the Site - Central andSouthern Areas of the Site

13Delineation and Remediation of Unexpected Impacts to Soil andGroundwater Quality Identified in Previously Inaccessible Areas of the Site -Central and Southern Areas of the Site

14 Post-Remediation Groundwater Monitoring

15 Remediation Closure and Reporting

Notes:

LNAPL Light Non_Aqueous Phase LiquidERD Enhanced Reductive Dechlorination

Anticipated Date for Task to be Undertaken

It is understood that the current employees’ car park is to be divested and redeveloped as a supermarket and petrol filling station. This area of the site has not been considered further, as none of the measured concentrations of contaminants in soil and/ or groundwater samples exceeded the derived SSAC.The tasks proposed and the asosciated timescales will be subject to the collection of further site-specific data and the proposed the pilot testing works.

Task

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LEGEND

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EXTENT OF SITE

0 6 12 18 24 303Metres

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Appendix ALegislative Context and Regulatory Guidance

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APPENDIX ARegulatory and Legislative Context

Land contamination is generally dealt with by the following types of regulation:

Acts of Parliament to investigate and remedy harm caused by land contamination; Conditions placed upon Planning Permissions for the redevelopment of land; and, Acts of Parliament and Regulations for the control of waste.

In Wales land contamination is identified and dealt with through Acts / Regulations including:

The Contaminated Land (Wales) Regulations (2006); Part IIA of the Environmental Protection Act (1990); The Environment Act 1995; The Town and Country Planning Act (1990); The Environmental Permitting (England and Wales) Regulations (2007); The Water Resources Act (1991); The Water Act (2003);; The Environmental Damage (Prevention and Remediation) (Wales) Regulations (2009); and, The Groundwater (England and Wales) Regulations (2009).

Part IIA of the Environmental Protection Act 1990

Part IIA of the Environmental Protection Act 1990 (which was inserted by Section 57 of theEnvironment Act 1995) created a regime for the identification and remediation of contaminated land.Section 78A(2) of the Environmental Protection Act 1990 defines contaminated land for the purposesof Part IIA as:

‘any land which appears to the local authority in whose area it is situated to be in such a condition, byreason of substances in, on or under the land, that;(a) significant harm is being caused or there is a significant possibility of such harm being caused; or(b) pollution of controlled waters is being, or is likely to be caused.’1

Harm is defined under section 78A of the Environmental Protection Act as meaning ‘harm to thehealth of living organisms or other interference with the ecological systems of which they form partand, in the case of man, includes harm to his property’. Types of harm are related to specificreceptors in order to determine whether they can be regarded as “significant”, as defined in Table A ofPart 3 of the Welsh Assembly Government (2006)2 statutory guidance.

Part IIA sets the definition of contaminated land within the context of the ‘suitable for use’ approach.The legal definition of contaminated land is also discussed within Statutory Guidance released byDEFRA (2008)3, although this is currently only applicable for England the paper was prepared inconsultation with the other UK countries.

The ‘suitable for use’ approach underlies the assessment process, and is based on the principles ofrisk assessment, including the concept of the ‘pollutant linkage’.

In the event that there are unacceptable levels of risk posed by a site, a remediation notice can beserved under the contaminated land regime introduced under Part IIA of the Environmental ProtectionAct 1990.

Regulation of Development on Land Affected by Contamination

1 Definition to be amended to “significant pollution of controlled waters is being caused or there is a significantpossibility of such pollution being caused” under the Water Act 20032 Part 2A. Statutory Guidance on Contaminated Land. Welsh Assembly Government, December 20063 Guidance on the legal definition of contaminated land. DEFRA July 2008

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Management of risks from contamination in development of land is also regulated in Wales under theTown and Country Planning Act 1990. Land contamination is a material planning consideration withinthis planning regime. The Local Planning Authority may impose conditions on the development duringplanning that include preliminary risk assessment, site investigation, risk assessment andremediation. The Environment Agency may use its role as a statutory consultee to provide the LocalPlanning Authority with advice.

Assessment of risk is again based on the pollutant linkage concept. The aim of risk management inthe development should be to render the land suitable for the proposed use and, therefore, to preventconsideration of the site under Part IIA.

The Welsh Assembly Government document Planning Policy Wales (March 2002) provides guidanceon the relationship between development and the management of risks from land contaminationcaused by historical use. The Building Regulations 2000, made under the Building Act 1984, alsorequire measures to be taken to protect new buildings and their occupants from the effects ofcontamination.

Voluntary Remediation Action

Voluntary remediation action on contamination resulting from historical activities can often anticipatefuture remediation requirements, such as through the Planning regime, and is encouraged, especiallywhere the site is not being assessed under Part IIA.

Environmental Damage

The Environmental Damage (Prevention and Remediation) Regulations 2009 came into force on 1st

March 2009 to implement EC Directive 2004/35 on environmental liability with regard to theprevention and remedying of environmental damage.

These Regulations do not apply retrospectively; environmental damage that took place before theRegulations came into force (1st March 2009), or damage that takes place (or is likely to take place)after that date but is caused by an incident, event or emission that occurred before that date areexempt from the requirements of the Regulations.

The Regulation is concerned with preventing environmental damage. It requires that all operators ofactivities that cause an imminent threat of environmental damage to take all reasonably practicalsteps to prevent the damage. Where damage has already been caused, the operator must take allreasonably practical steps to prevent further damage from occurring.

Non-statutory regulatory technical guidance Documents

The UK non-statutory regulatory technical guidance on the assessment of land contamination,primarily released as part of the Contaminated Land Exposure Assessment (CLEA) methodology(DEFRA and EA) has recently been updated. New guidance has been released by the EA, for use inEngland and Wales. The following documents currently present guiding principles in investigating andassessing potentially contaminated land, which are generally adopted in considering sites within anyof the legal frameworks discussed above, or when considering voluntary remediation action:

Investigation of potentially contaminated sites – Code of Practice (British Standard 10175:2001).

Contaminated Land Report CLR11 Model Procedures for the Management of LandContamination. (DEFRA and EA, 2004).

Human health toxicological assessment of contaminants in soil Environment Agency ScienceReport SC050021/SR2 (EA, 2009)

Updated technical background to the CLEA model Environment Agency Science ReportSC050021/SR3 (EA, 2009)

Compilation of Data for Priority Organic Pollutants for Derivation of Soil Guideline ValuesEnvironment Agency Science Report SC050021/SR7 (EA, 2008)

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An ecological risk assessment framework for contaminants in soil. Environment AgencyScience Report SC070009/SR1 and related reports S2a-e

Groundwater Protection: Policy and Practice, Environment Agency GP3 Parts 1-4 Remedial Targets Methodology: Hydrogeological Risk Assessment for Land Contamination

(EA of England and Wales, 2006) developed in consultation with the Scottish EnvironmentProtection Agency (SEPA) and the Northern Ireland Heritage and Environment Service.

Assessing risks posed by hazardous ground gases to buildings Report C665 (CIRIA, 2007) BS 8485:2007 Code of practice for the characterization and remediation from ground gas in

affected developments(British Standards Institution, 2007) Risk Based Corrective Action (RBCA) Methodology (ASTM designation E1739-95, E2081-

00). DoE Industry Profiles