13Contaminated Land

13 Contaminated Land

13 CONTAMINATED LAND

13.1 Introduction

a) Scope of Assessment 13.1.1 This Chapter of the Environmental Appraisal (EnvApp) provides an assessment of the current status of land contamination within the Hinkley C Development Site and the potential effects that construction and operation of the development may have with regard to the disturbance and mobilisation of potential contaminants present within the site. The following aspects are covered:

 Identification of the extent, type and likelihood of contamination within soils/land in the study area;  Assessment of the capacity of scheme construction and operation to cause disturbance to potentially contaminated land; and  Recommend management strategies, if determined necessary, to deal with potential disturbance to contaminated land and the mobilisation of contaminants.

13.1.2 The site boundary and study area for this assessment is shown in Figure 13.1. A detailed description of the proposed development is provided in Chapter 2, Volume 2 of the EnvApp. 13.1.3 The data presented within this chapter is limited to the areas investigated as part of the fieldworks, the visual observations at the time of the fieldworks and chemical analyses taken on the samples collected from site. Given the potential sources of contamination identified on areas which have not been subjected to site investigation, and without the necessary intrusive investigation data, further potential risk from contamination and the associated impacts cannot be discounted from areas that have not been subjected to site investigation. b) Legislation, Policy and Guidance 13.1.4 Aspects of legislation, planning policy and guidance of relevance to the Development Site and the management of contaminated land are presented below. i) European legislation Directive on Integrated Pollution and Prevention and Control (96/61/EC) 13.1.5 This Directive aims to prevent and/or reduce pollution to air, land or water from a wide range of industrial and agricultural activities in an integrated manner. 13.1.6 Industrial and/or agricultural activities listed by the Directive must be operated under a permit issued by the competent authority (in this case the Environment Agency). The permit must specify conditions on the operation of the plant including:

 Emission limits for certain substances to air, land and/or water;  The use of best available techniques (BAT)1 to prevent and/or minimise pollution of the environment;

1 A series of detailed technical guidance documents known as BREF on BAT for each of the industrial and agricultural processes covered by the Directive have been prepared by the Commission and should be adopted by all competent authorities when writing their permits

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 Consumption of raw materials, energy efficiency, heat, noise, light and vibrations and accident prevention; and  Waste management practices to avoid pollution following closure of the site.

13.1.7 The Directive was originally implemented in England by the Pollution, Prevention and Control (England and Wales) Regulations 2000; however, these have since been superseded by the Environmental Permitting (England and Wales) Regulations 2007 (SI 2007/3538) and 2010 (SI 2010/675). The Water Framework Directive (2000/60/EC) 13.1.8 The overall purpose of the Directive is to establish a framework for the protection of surface fresh water, estuaries, coastal water and groundwater. The objectives of the Directive are to enhance the status and prevent further deterioration of aquatic ecosystems and associated wetlands, promote the sustainable use of water, reduce pollution of water (especially by ‘priority’ and ‘priority hazardous’ substances), and ensure progressive reduction of groundwater pollution. Among the main features of the Directive are:

 Member states should take all necessary measures to ensure that groundwater quality does not deteriorate and to prevent the input of pollutants to groundwater;  Discharges of hazardous substances must cease or be phased out within 20 years of their identification as a priority hazardous substance; and  All inland and coastal waters within defined river basin districts must reach at least good status by 2015.

13.1.9 In England and Wales, the Directive is being implemented through the Water Environment (Water Framework Directive) England and Wales Regulations 2003. Groundwater Directive (80/68/EEC) 13.1.10 This Directive aims to protect groundwater against pollution caused by dangerous substances, however it is due to be repealed in 2013 by the Water Framework Directive (2000/60/E). The Directive required the prevention of the discharge of List I substances to groundwater, and the investigation of List II substances prior to direct or indirect discharge, and is implemented in England and Wales by the Environmental Permitting (England and Wales) Regualtions 2010 (SI 2010/675) 13.1.11 The EU Directive on the Protection of Groundwater Against Pollution and Deterioration (2006/118/EC) aims to ensure good groundwater quality by 2015, in line with the requirements of the Water Framework Directive, and sets out specific measures for preventing and controlling groundwater against pollution and deterioration. The Landfill Directive (99/31/EC) 13.1.12 This Directive sets out the requirements for the location, management, engineering, closure and monitoring for landfills and includes requirements relating to the characteristics of waste to be landfilled and definitions of types of landfill sites. The Directive categorises landfills into those that can accept either hazardous, non hazardous or inert wastes and defines waste acceptance criteria. The Directive also covers internal waste disposal sites (i.e. where waste is disposed of at or on the site of production). Temporary storage of waste for a period of greater than twelve months also meets the definition of a landfill and therefore falls under the requirements of the Directive. 13.1.13 The Directive is implemented in England and Wales by the Environmental Permiting (England and Walse) Regulations 2010 (SI 2010/675).

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land 13.1.14 The above EU Directives are implemented in the UK though a series of primary (Acts) and secondary legislation (Regulations). ii) National legislation Environmental Protection Act 1990 and associated Contaminated Land Regulations 2006 (SI 2006/2989) 13.1.15 The introduction of the Environment Act 1995 resulted in the addition of Part IIA to the Environmental Protection Act 1990. This Act contains the primary legislation relating to the identification, assessment and remediation of contaminated land and groundwater in the UK. Part IIA (as it is more commonly known) includes a statutory definition of contaminated land, which is: ‘land which appears to be in such a condition, by reason of substances in, on or under the land, that a) Significant harm is being caused or there is the significant possibility of such harm being caused, or b) Pollution of controlled waters is being, or is likely to be caused.’ 13.1.16 Tables A and B of the statutory guidance circular 02/2000 defines statutory receptors under Part IIA, which include:

 Human beings;  Various ecological systems and designated ecological sites;  Property including crops, produce, livestock and wild animals which are the subject of shooting or fishing rights; and  Buildings and Services.

13.1.17 The Contaminated Land Regulations 2006 consolidate the earlier Contaminated Land (England) Regulations, 2000 and also include measures to cover matters relating to radioactively contaminated land (only associated with radioactivity arising from historical practices or works not naturally occurring e.g. radon). The Regulations give the Health and Safety Executive (HSE) the power to deal with radioactive contaminated land on a site licensed under the Nuclear Installations Act 1965 (i.e. in such cases Part IIA will not apply, at least with respect to any radioactive contamination). 13.1.18 The assessment and determination of contaminated land is based around the ‘source-pathway- target’ approach, whereby a linkage (known as a ‘pollutant linkage’ in Part IIA) must be shown to exist between the source of contamination and a target. A pathway could, for example, be a drain or service trench or permeable ground connecting a source to a target. 13.1.19 Part 4 A.37 of the statutory guidance circular 02/ 2000 states that land should not be designated as contaminated land where:

 A substance is already present in controlled waters;  Entry into controlled waters of that substance from the land has ceased; and  It is not likely that further entry will take place.

Control of Pollution (Oil Storage) (England) Regulations 2001 (SI 2001/2954) 13.1.20 The Regulations have been introduced to reduce the risk of land contamination and water pollution from oil storage, and apply to anyone storing greater than 200 litres of oil in above ground tanks (underground storage is covered by the Environmental Permitting (England and Wales) Regulations 2010) and detail the construction requirement for building of tanks. Oil is

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 3 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land defined in the Regulations as ‘any kind of oil and includes petrol’. The Regulations do not apply to the following:

 Oil storage inside buildings;  Waste oil;  Oil refineries; or  Distribution of oil to other places.

Environmental Permitting (England and Wales) Regulations 2010 (SI 2010/675)) 13.1.21 The Regulations aim to create a single permitting and compliance scheme for sites and processes previously regulated under the Integrated Pollution Prevention and Control (IPPC), Pollution, Prevention and Control (PPC), Waste Management Licensing (WML) and Landfill Regulations. An environmental permit is now required for all processes and activities listed in Schedule 1 of the Regulations and includes (for example) energy, metals, mineral, chemicals and waste management activities. Some waste management operations are excluded from environmental permitting because they are regulated under other regimes or because they are a lower risk activity which can be undertaken under a registered/approved exemption. 13.1.22 The Regulations also implement the European Landfill Directive (1999/31/EC), replacing the landfill licensing regime established under Environmental Protection Act 1990, the Waste Management Licensing Regulations 1994 and latterly the Landfill (England and Wales) Regulations 2002 and Environmental Permitting (England and Wales) 2007. They set out requirements for the classification and management of landfill sites including the definition of a landfill site. Under the Regulations, as well as complying with the Duty of Care Waste, producers are responsible for ensuring that receiving landfill sites have appropriate licences or permits for the type of waste sent for disposal. 13.1.23 In addition, the Regulations implement the EC Groundwater Directive (80/68/ECC). 13.1.24 The Regulations aim to ensure a high level of environmental protection by preventing, or where this is not practicable, reducing emissions to air, land and/or water from regulated processes. The permits must include conditions to ensure that no significant pollution is caused by an activity, and that all measures are taken into account to prevent pollution. Such conditions may require the use of Best Available Techniques (BAT) to prevent or reduce emissions. In determining BAT, the regulator must have regard to any statutory BAT guidance e.g. sector and process guidance notes and/or EU BREF guidance notes. 13.1.25 Permits will also have to include conditions to ensure:

 Protection of soil and groundwater;  The establishment of suitable emissions and environmental monitoring;  The implementation of measures to prevent accidents and accidental releases;  When activities cease on site, measures to ensure the site is returned to a satisfactory condition and residual pollution risk removed.

Environment Agency Pollution Prevention Guidelines 13.1.26 A number of Pollution Prevention Guideline (PPG) documents have been produced by the Environment Agency to provide practical advice to industry and the public regarding the prevention of pollution of surface water, groundwater and land from activities such as storage of oils and fuels, refueling activities, construction and demolition practices, fire water management and vehicle washing. Planning Policy Statement 23: Planning and Pollution Control (PPS23) - Annex 2: Development on Land Impacted by Contamination

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land 13.1.27 PPS23 is intended to complement the pollution control framework under the Pollution Prevention and Control Act 1999 and the Pollution Prevention and Control Regulations 2000. It replaces Planning Policy Guidance 23: Planning and Pollution Control (PPG23). 13.1.28 The main regulatory control aims to ensure that contaminated land is not used unsuitably. Contaminated land controlled through the planning process does not have a specific definition as it does under Part IIA, and unlike Part IIA (which is just concerned with the land in its current state) the planning system considers the site in its current and proposed use. To avoid the potential for confusion, PPS23 uses the wider term of ‘land affected by contamination’ to differentiate it from contaminated land under Part llA. 13.1.29 PPS23 provides guidance for the development of land impacted by contamination. The main planning objective is to ensure that any unacceptable risks to human health, buildings, natural and historical environment from contamination are identified so that appropriate action is taken to remove or mitigate those risks to acceptable levels and ensuring that the development is ‘suitable for use’. It is the responsibility of the developer to ensure that where a site is contaminated or suspected of being contaminated it is properly investigated, assessed and where necessary remediated to ensure the site is suitable for use. 13.1.30 Controls on the development of such sites are usually through specific contaminated land/land quality conditions in the planning permission. PPS23 also advises that developers should be aware that actions or omissions on their part could lead to liability being incurred under Part IIA where a development fails to address an existing unacceptable risk or creates a risk by introducing a new receptor or pathway. PPS23 also states that one of the objectives of the planning process in controlling contaminated land development is to ensure that as a minimum, after carrying out the development and commencement of its use, the land should not be capable of being subsequently determined as contaminated land under Part IIA of the EPA 1990. Environment Agency (2004). Contaminated Land Note 11, Model Procedures for the Management of Land Contamination 13.1.31 This provides the technical framework for applying a risk management process when dealing with land impacted by contamination. The technical approach presented in the Model Procedures is designed to be applicable to a range of non-regulatory and regulatory contexts. These include:

 Development or redevelopment of land under the planning regime;  Regulatory intervention under Part IIA of the Environment Protection Act 1990;  Voluntary investigation and remediation; and  Managing potential liabilities of those responsible for individual sites or a portfolio of sites.

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13.2 Assessment Methodology

a) Introduction 13.2.1 This aspect of the environmental assessment process focuses on the potential existence of contaminants within the soils of the Development Site and the potential risk that disturbance and mobilisation of contaminants during construction activities (e.g. earthmoving, excavation) and operation may pose to sensitive receptors (e.g. site workforce). The approach taken has been, through review of available information and specific data collected through site investigation, to determine the presence and nature of any potential contaminants within the soils (natural and previously disturbed by human activity) in the Development Site. Screening criteria and thresholds gained from various sources have then been utilised to determine whether contaminant levels present are likely to pose a risk if, during construction and/or operation these contaminants were to be mobilised and become available for uptake. Where, through this analysis, potential risks have been determined, options for managing the construction and operational works in order to minimise potential risk associated with disturbance to and mobilisation of potential contaminants are identified. The following sections provide a summary of this process and information on the investigation work undertaken. b) Data and sources of information 13.2.2 The following information sources have been used to assist in establishing the baseline conditions:

 Ordnance Survey (2005) Explorer Map 1:25,000 scale ‘Quantock Hills & Bridgwater’ Sheet 140 (Ref. 13.1)  British Geological Survey (BGS) 1:50000 BGS Sheet 279; Weston-Super-Mare (Ref. 13.2)  Whittaker, A and Green, G.W. (1983). Geology of the country around Weston-Super-Mare: Memoir for 1:50000 geological sheet 279, New Series, with parts of sheets 263 and 295. Institute of Geological Sciences. London (Ref. 13.3)  Rendel Palmer and Tritton (1986). Hinkley Point ‘C’ Power Station Pre-Application Studies, Volume 2 Geotechnical Report (Ref. 13.4)  Allot Atkins Mouchel (1988). Hinkley point ‘C’ Power Station Geotechnical Studies, Geotechnical Summary Report – Chapter 7. Report Ref: HPC 1101/57 (Ref. 13.5)  Aspinwall & Company (1996). Analysis of Groundwater Conditions at Hinkley Power Station. Report Ref: NU5101B for Nuclear Electric (Ref. 13.6). c) Surveys and studies 13.2.3 To date a desk based assessment and series of site walkover and intrusive investigations have been undertaken, covering a large part of the proposed Development Site. This work has been phased, with the initial desk study being used to determine the likely presence and nature of contaminants and to determine the need for and facilitate the intrusive investigation work. The Phase 1 Desk Based Assessment covers the entire Development Site together with a review and synthesis of existing reports relating to the Hinkley Point Power Station Complex. The findings from these initial surveys and the desk based assessment are referred to in the baseline analysis presented in Section 13.3. Surveys covering the Built Development Area East and the Southern Construction Phase Area are, at the time or writing, being progressed. The results from these surveys will be made available for the DCO application.

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land 13.2.4 The following sections provide a description of these studies, broken down into the individual areas of the Development Site (Built Development Area West, Built Development Area East and Southern Construction Phase Area). d) Built Development Area West 13.2.5 To date, a Phase 1 Desk Study and Preliminary Assessment (Ref. 13.7) and a Phase 2 Supplementary Investigation for the Built Development Area West have been undertaken (Ref. 13.8). Limited further investigations of the Built Development Area West are also being conducted as part of the ongoing second onshore investigation. To date, four additional trial pits have been excavated on the Built Development Area West and the results have been included in this report, a further four are proposed. 13.2.6 The Phase 1 Desk Study and Preliminary Assessment Report (Ref 13.7) presents the findings of the non-radiological preliminary site investigation of the near surface soils (<0.3 m bgl) on the Built Development Area West. The investigation was carried out in July 2008 and comprised the excavation of 30 hand auger holes to a depth of 0.3 m below ground level (bgl). Samples comprised natural superficial deposits. Sampling locations are presented on Figure 13.2. Analytical results, details of methodology, photographic evidence and hand auger descriptions are included within the Phase 1 Desk Study report (Ref. 13.7). 13.2.7 Soil samples were analysed for the following determinands:

 25 samples for core suite; arsenic, cadmium, chromium, lead, mercury, copper, nickel, zinc, selenium, water soluble boron, pH;  10 samples for Total Petroleum Hydrocarbons (TPH C8-C35);  20 samples for speciated Polyaromatic Hydrocarbons (PAHs);  5 samples for speciated Total Petroleum Hydrocarbons (TPH);  15 samples for Volatile Organic Compounds (VOCs); and  15 samples for asbestos.

13.2.8 The Phase 2 Supplementary Investigation was undertaken to assess the contamination status of the deeper site soils (>0.3 m bgl up to 5.0 m bgl) on the Built Development Area West. 13.2.9 The non radiological supplementary investigation of the Built Development Area West was carried out in October 2008 and was undertaken as part of the extensive first on shore investigation. A total of 26 trial trenches were excavated to a depth between 0.55 m and 5.0 m bgl across the Built Development Area West allowing for the collection of 79 soil samples. The locations of the sampling are presented on Figure 13.2. Made Ground was encountered at one location (TRE21) extending to a depth of 0.33 m bgl. In all other trenches the materials encountered predominantly comprised superficial drift deposits and weathered bedrock. 13.2.10 Soil samples recovered from the trial pits were analysed for the following determinants:

 37 samples for core suite: arsenic, cadmium, chromium, lead, mercury, copper, nickel, zinc, selenium, water soluble boron, pH;  14 samples for Total Petroleum Hydrocarbons (TPH C8-C35);  31 samples for speciated Polyaromatic Hydrocarbons (PAHs);  7 samples speciated Total Petroleum Hydrocarbons;  17 samples for Volatile Organic Compounds (VOCs); and  3 samples for asbestos.

13.2.11 As part of the ongoing second onshore investigation a number of exploratory holes are being advanced to supplement previous investigations, to investigate the shallow made ground deposits in the area of former Benhole Farm and areas of possibly infilled ponds. The second

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 7 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land onshore investigation is currently ongoing, in January 2010 four pits had been advanced for contamination assessment purposes, to a maximum depth of 5 m bgl; three with the vicinity of former Benhole Farm and one towards the south-east. The sampling locations are presented on Figure 13.2. 13.2.12 A total of eight samples have been collected from these trail pits comprising four samples of made ground (one from each location between 0.0 – 0.3 m) and three samples of natural ground (>0.3 m). Samples were analysed for the following:

 6 samples for metals and metalloids; arsenic, cadmium, chromium, hexavalent chromium, lead, mercury, nickel, copper, zinc, selenium water soluble boron and pH;  1 sample of Made Ground for heavy metals only; arsenic, cadmium, chromium, lead, mercury, nickel, copper, zinc, selenium water;  2 samples of Made Ground for total sulphate, total cyanide, sulphide, elemental sulphur, total monohydric phenols;  4 samples for Soil Organic Matter (SOM);  2 samples of Made Ground for Total Petroleum Hydrocarbons (TPH) C8-C35;  3 samples for polyaromatic hydrocarbons (PAHs); and  1 sample of Made Ground for asbestos.

13.2.13 A series of assessments relating to the radiological conditions on the Built Development Area West have been undertaken. A baseline radiological survey was undertaken, which involved a non-intrusive radiological survey, including a radiological walkover survey and environmental gamma dose rate measurements, together with an intrusive investigation involving the collection and radiochemical analysis of surface soil samples (surface scrapes < 0.2 mbgl). The area over which the non-intrusive radiological survey was carried out; together with locations of the associated surface soil collection points are presented on Figure 13.3. 13.2.14 The site works were carried out in July 2008. The site radiation walkover recorded measurements that were low, being at or below expected background values for the area. 13.2.15 A baseline intrusive survey was carried out, which involved the collection and radiochemical analysis of 20 near-surface soil samples. The samples were analysed for the following determinands: gross alpha (calibrated with americium-241); gross beta (calibrated with potassium-40); high-resolution gamma spectrometry and water-extractable tritium. 13.2.16 The information obtained during the baseline intrusive survey was supplemented with a Phase 2 Supplementary Investigation of Potential Radiological Contamination for the Built Development Area West (Ref. 13.8). Soil samples were collected from the trial trenches excavated in 2008. 13.2.17 Thirty soil samples from depths >0.2 mbgl were selected for radiochemical analysis for the following determinands: gross alpha (calibrated with americium-241); gross beta (calibrated with potassium-40); high-resolution gamma spectrometry, total tritium and carbon-14. The samples analysed were selected to assess the contamination status of the deeper site soils. Analytical reports, details of methodology etc. are included within the Phase 2 Supplementary Investigation of Potential Radiological Contamination Report (Ref. 13.8) i) Built Development Area East 13.2.18 The Preliminary Phase 2 Contamination Assessment (Non Radiological) of the Built Development Area East presented the findings of the non-radiological investigation on the Built Development Area East carried out between November 2009 and February 2010. The investigations were undertaken as part of the extensive second on shore investigation which is

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land still on going. Therefore the information presented is preliminary and will be updated for the final DCO Application. 13.2.19 In order to facilitate the investigation of the Built Development Area East, the area was subdivided into six assessment areas based on current and historical land use and topography. These areas are presented on Figure 13.4 . The investigations comprised the advancement of 49 trial pits excavated up to between 0.5 m and 5.6 m bgl, 8 boreholes for gas monitoring purposes drilled to depths of up to 9.9 m bgl, 12 boreholes for groundwater monitoring purposes drilled to depths of up to 16.05 m bgl and 7 windowless sampling holes advanced to up to 4.2 m bgl. In addition, a number of additional exploratory holes were excavated to delineate the presence of asbestos containing materials. These comprised 8 trial pits excavated up to 5 m bgl, 9 windowless sampling holes advanced to depths up to 4.6 m bgl and 8 hand pits dug to depths up to 1.0 m bgl. The locations of the exploratory holes are presented on Figure 13.4. 13.2.20 A total of 171 samples were scheduled for analysis of the following ‘core’ suite comprising:

 Arsenic, cadmium, chromium, lead, mercury, selenium, boron (water soluble), copper, nickel, zinc, pH, sulphate (total), phenols (total) cyanide (total), sulphur, sulphide, PAH total, speciated PAHs, and total TPH (C8-C35).

13.2.21 In addition, selected samples were analysed for the following:

 A total of 47 samples were scheduled for analysis of speciated total petroleum hydrocarbons (TPH CWG) with an aliphatic and aromatic carbon fraction speciation;  A total of 40 samples were scheduled for analysis of Volatile Organic Compounds (VOCs);  A total of 33 samples were scheduled for analysis of Semi-Volatile Organic Compounds (SVOCs);  157 samples for asbestos screen and identification;  22 samples for Waste Acceptance Criteria; and  9 samples for soil leachate analysis.

13.2.22 Similarly to the Built Development Area West, a series of assessments relating to the radiological conditions on the Built Development Area East have been undertaken. 13.2.23 A non-intrusive radiological survey, including a radiological walkover survey and environmental gamma dose rate measurements, was undertaken in December 2009 prior to the commencement of intrusive works. The survey locations are presented in Figure 13.5 a & b. 13.2.24 Following the non-intrusive radiological survey, the Phase 2 intrusive works on the Built Development Area East land commenced. From the intrusive investigations to date, which have consisted of boreholes and trial pits, a total of 120 soil samples have been collected and submitted for radiochemical analysis for the following determinands: gross alpha (calibrated with americium-241); gross beta (calibrated with potassium-40); high-resolution gamma spectrometry; total tritium; and carbon-14. Analytical results are currently available for 68 of the samples. Figure 13.3 provides the locations from which the samples analysed were collected. ii) Southern Construction Phase Area 13.2.25 No intrusive investigations within the Southern Construction Phase Area have been undertaken to date. Although the southern lane is nto expected to be contaminated, having a long history of agricultural use investigation work similar to that undertaken for the other areas has been planned and will commence later in 2010. The results from these investigations will be provided in the final ES to accompany the DCO application.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 9 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land 13.2.26 A non intrusive radiological survey, comprising environmental gamma dose rate measurements, was undertaken in October 2009 prior to the commencement of intrusive investigations. The survey locations are presented on Figure 13.6. iii) Ground gas monitoring 13.2.27 A programme of ground gas monitoring has been undertaken within the Built Development Area West (Ground Gas Risk Assessment). Six gas monitoring visits were carried out between January 2009 and April 2009 at ten borehole locations, as presented on Figure 13.7. Gas monitoring was undertaken in accordance with requirements set out in guidance document Construction Industry Research and Information Association (CIRIA) 665 ‘Assessing risks posed by hazardous ground gases to buildings’ (2007) (Ref. 13.9). 13.2.28 During one visit, six gas samples were taken from selected locations and submitted for laboratory analysis to determine concentrations of methane, carbon dioxide, oxygen, carbon monoxide, hydrogen sulphide, nitrogen, hydrocarbons (n-alkanes) C1 to C8 and volatile organic compounds. The laboratory analysis was intended to facilitate verification of the field monitoring data. e) Risk assessment 13.2.29 The risk assessment process has been facilitated by the use of a Preliminary Conceptual Site Model (PCSM) as an initial step in the process of assessing risk related to contaminated land. A Conceptual Site Model (CSM) is defined within the British Standard BS 10175 – Investigation of Potentially Contaminated sites – Code of Practice (2001) as follows: “Textural and/or schematic hypothesis of the nature and sources of contamination, potential migration pathways and potential receptors, developed on the basis of the information from preliminary investigation and which is an essential part of the risk assessment process” 13.2.30 A pollutant linkage may exist where a source of contamination is present that may interact with a receptor (target) via a pathway. The source, pathway and receptor are defined as follows:

 SOURCE – Location from which contamination is, or was, derived;  PATHWAY – Mechanism or route by which a contaminant comes into contact with, or otherwise affects, a receptor; and  RECEPTOR (target) – Persons, living organisms, ecological systems, controlled waters, atmosphere, structures and utilities that could be adversely affected by the contaminant(s).

13.2.31 The PCSM is holistic, and has evolved through the various phases of investigation work undertaken as more detailed information has become available, allowing potential pollutant linkages to be validated or discounted. 13.2.32 Following development of the PCSM, the data on potential contaminants collected via the intrusive investigations has been subject to a Tier 1 Risk Assessment by comparing the values of contaminants recorded against a suite of screening criteria. These criteria have been obtained from a variety of sources as set out in Table 13.1. Table 13.1: Generic Screening Criteria

Environmental Media Generic Screening Criteria

Soil Human health risk 1. Soil Screening Values (SSVs) using CLEA v1.06, using all the same standard parameters the Environment Agency used to derive standard UK Soil Guideline Values for commercial and

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

industrial end use, with the exception the soil organic matter has been set to 1%. 2. DEFRA/EA 2002. Research and Development Publication SGV 10. Soil Guideline Values for Lead Contamination.

3. BS3882:2007 Specification for topsoil requirements for use. 4. Hazardous Waste (England and Wales) Regulations 2005/Chemical (Hazard Information and Packaging Supply) Regulations 2002. Phytotoxic risk 5. Former ICRCL 59/83 (N.B. Paper withdrawn by DEFRA in 2004)

6. Statutory Instrument 1989 No 1263, ‘Sludge Use in Agriculture Regulations (1989) (pH value >7). Built environment risk

7. BRE Special Digest 1(3rd Edition) (2005) Concrete in Aggressive Ground. 8. Water Regulations Advisory Service (WRAS) Guidance Note 9- 04-02 2002. The Selection of Materials for Water Supply Pipes to be Laid in Contaminated Land. 9.Wessex Water Soil Survey Guidance.

Ecotoxicological risk 10. UK and international ecological/ecotoxicological Soil Screening Values. Environment Agency ‘An ecological risk assessment (ERA) framework for contaminated soils,’ October 2008.

Groundwater 1. UK/EC/ WHO Drinking Water Standards and Freshwater and Saline Environmental Quality Standards.

Ground Gas 1. CIRIA 665.

f) Stakeholder Consultation 13.2.33 A number of meetings and correspondence with the local authorities (West Somerset Council and Sedgemoor District Council) and the Environment Agency have been undertaken. This consultation has focused on setting out and agreeing the scope of the investigations undertaken, agreeing changes to this scope and the presentation of initial results. The scope of work described in this document reflects their comments and advice, as appropriate. g) Limitations and assumptions 13.2.34 Intrusive investigations, including sampling testing and monitoring of environmental media (soils, groundwater and ground gas) within the Built Development Area East and Southern Construction Phase Area are still ongoing. Therefore, the current assessment of contaminated soils risk within these areas is based on Phase 1a desk study information and the Preliminary Phase 2 Contamination Assessment for the Built Development Area East only (Ref. 13.7 & 13.8).

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13.3 Baseline Environmental Characteristics

a) Introduction 13.3.1 This section presents the baseline environmental characteristics for the proposed Development Site and surrounding areas with specific reference to contaminated land. 13.3.2 Figure 13.1 illustrates the study area boundary and the extent of the three areas forming the Development Site (the Built Development Area West, Built Development Area East and Southern Consutruction Phase Area). 13.3.3 With respect to contamination, the description of baseline conditions predominantly concerns issues relating to actual and potential contamination by non-radiological and radiological contaminants. A description of baseline conditions with respect to soil characteristics relevant to land use potential and agricultural land quality grading is provided within Chapter 12 on Land Use and Soils. i) Description of landuse within the Development Site 13.3.4 In general terms, the topography of the study area comprises of undulating countryside, terminating at Bridgwater Bay to the north at a natural cliff line which descends to a shingle beach. 13.3.5 Across the Development Site ground elevations range from approximately 10 m above ordnance datum (AOD) to 35 m AOD and across the Southern Construction Phase Area ground elevations range from approximately 5 m AOD to 28 m AOD. ii) Man-made features 13.3.6 The majority of man-made topographical features present within the study area are located within the Built Development Area East which include: the spoil mounds; the former Hinkley Point Power Station Visitor Centre; an overflow car park and a helicopter landing pad used by the Royal Air Force in the northeast corner of the Built Development Area East. There is also surface evidence (in the form of a degraded concrete slab) of a former sewage works which was located adjacent to the boundary of the Built Development Area East and Built Development Area West. 13.3.7 Within the Built Development Area West, there are three derelict barn buildings. One is located close to Wick Moor Drove, and the others are located towards the centre of this area. The archaeological significance of these structures is considered within the Environmental Appraisal Chapter on Archaeology and Cultural Heritage. 13.3.8 A number of minor surface watercourses are present within the study area. Holford Stream runs west to east within the northern part of the Southern Construction Phase Area. This watercourse flows under Wick Moor Drove and drains into Wick Moor to the east. There is also a series of agricultural drainage ditches present on site, running along field boundaries. Two drainage ditches are present on the Built Development Area West, one running west to east along a field boundary in the northern part of this land parcel before turning northwards towards the coastline (as referred to above). The other drains run west to east at the base of the depression along the boundary of the Built Development Area West and the Southern Construction Phase Area. Site reconnaissance has confirmed these drainage ditches to be ephemeral (i.e. seasonally dry) water features. 13.3.9 The Ordnance Survey map (Ref. 13.1) indicates two ponds to be present, one in the northwestern part of the study area and one adjacent to Holford Stream. Site reconnaissance identified the pond in the north-western area to be seasonally dry.

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land iii) Made Ground 13.3.10 Intrusive investigations of the Built Development Area West confirmed the absence of any Made Ground in this area (with ground conditions largely comprising topsoil over natural deposits), with the exception of one isolated area of shallow made ground associated with the historical farm buildings (Benhole Farm) in the northwestern area of the Built Development Area West. 13.3.11 As part of the Phase 2 supplementary investigation one location in this area of the Built Development Area West identified made ground deposits comprising slightly gravely cobbly sandy clay with occasional gravel, bricks, glass and clay tile, to a depth of 0.33 m. Further investigations, conducted as part of the second on shore investigation, identified further deposits at two locations in this area, comprising soft dark brown slightly gravely clay with rare fragments of red brick and mortar to between 0.25 m and 0.3 m, underlain by a layer of limestone gravel and cobbles to between 0.3 m and 0.4 m. 13.3.12 The investigations conducted as part of the Preliminary Phase 2 Contamination Assessment of the Built Development Area East, identified varying depths of made ground across this area, ranging from absent to proven depths of 9.0 m within the mounds. Made ground deposits have been found to typically comprise either reworked natural soils (weathered Blue Lias formation deposits comprising mudstone and limestone), or demolition and construction waste materials. 13.3.13 There are no known made ground deposits on the Southern Construction Phase Area, which is consistent with the recorded agricultural and use in this area. However this has yet to be confirmed through intrusive investigations. b) Description of land contamination conditions 13.3.14 This section focuses upon the characterisation of baseline soil conditions with respect to radiological and non-radiological chemical contamination. It also describes baseline contamination characteristics with respect to ground gases as these are often mutually linked to physical and chemical soil conditions and contamination status. i) Historic use of the Development Site and potential sources of contamination 13.3.15 A review of historical maps and plans included within relevant reports (see list in Section 2) has identified that both the Built Development Area West and the Southern Construction Phase Area have remained as greenfield agricultural land since the earliest available map (published in 1886). Within the Built Development Area West Benhole Farm was located on the north western corner until around 1976 when it was demolished to leave a single remnant outbuilding which is still present, along with two other derelict farm buildings. The historical maps and plans also indicate a number of historical ponds on site, some of which appear to have been infilled. 13.3.16 Within the Southern Construction Phase Area a number of historical ponds have been identified on site, although all but one now appear to have been infilled. Also, a property is identified as being on site from 1886 (Corner Farm), which by 1975 had become derelict and by 2002 had been removed. 13.3.17 The Built Development Area East comprised greenfield, predominantly agricultural land, until the late 1958 when a former fabrication and construction area was constructed predominantly on the north eastern area, during the construction of Hinkley point A. Photographic evidence shows the presence of a number of large fabrication buildings and cranes with associates trackways and spoil deposition in the area of the existing mound feature until 1965 Figure 13.8. 13.3.18 In 1975 a small sewage works was constructed towards the western boundary. During construction of the Hinkley Point B Power Station an accommodation/construction camp and fabrication area with associated electrical sub stations were developed on the eastern and north-eastern sections of the area. By 2005, a visitors' centre had also been constructed in this

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 13 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land area. The Built Development Area East lies within the existing Hinkley Point Power Station Complex but is not in intensive use. 13.3.19 Surrounding the Development Site, land use has remained predominantly agricultural with the exception of the construction and operation of the Hinkley Point Power Station Complex to the east. 13.3.20 From the desk based assessments a number of salient features and potential sources of contamination have been identified for each area. These are summarised as follows, with locations presented on Figure 13.8:

 Southern Construction Phase Area – historical use as agricultural land i.e. agricultural crop management and sewage and sludge application, the possible storage and maintenance of vehicles and chemicals within farm buildings leading to potential isolated hotspots of contamination, derelict farm buildings. The potential for localised infilling of former pond areas and naturally enriched organic/alluvial deposits;  Built Development Area West - historical use of the site as agricultural land i.e. agricultural crop management and sewage and sludge application, the possible storage and maintenance of vehicles and chemicals within farm buildings leading to potential isolated hotspots of contamination, derelict farm buildings and the potential for localised infilling of former pond areas; and  Built Development Area East – infiiled ponds, identified areas of waste disposal/landfill, waste management site, historical sewage works, former contractors accommodation/fabrication compound and associated electrical substations, fuel oil storage tanks and boiler houses, excess spoil mound arising from the construction of the Hinkley Point Power Station Complex.

13.3.21 Within the Built Development Area West and the Southern Construction Phase Area the salient features and potential pollutant sources are largely limited to infilled ponds and historical farm buildings. 13.3.22 The majority of the identified salient features and potential pollution sources identified on the study area are within the Built Development Area East. Key features include the former sewage works (ID 22), a licensed waste management site (ID 14), areas of waste disposal/landfill and the former accommodation/fabrication compound and associated electrical substations and fuel oil storage tanks and boiler houses (locations are presented on Figure 13.8). 13.3.23 The desk based assessments also identified that there is the potential for low levels of radionuclide ‘fallout’ due to the proximity of the study area to the existing Hinkley Point Power Station Complex (radiological aspects are described in more detail in Chapter 20 of the Envinmental Appraisal). ii) Intrusive investigation findings Built Development Area West 13.3.24 The Phase 1 Desk Study and Preliminary Assessment Report (Ref. 13.7) presents the findings of the non-radiological preliminary site investigation of the near surface soils (<0.3 m bgl) on the Built Development Area West. The results from this survey work are summarised in Table 13.2. A preliminary (Tier 1) risk assessment was undertaken and the chemical testing data were compared to generic assessment criteria (Soil Screening Values (SSVs)) applicable to a commercial/industrial end use which is appropriate given the proposed development of the site for a new power station and WRAS guidlines.

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Table 13.2: Summary of Chemical Analysis Results for Near Surface Soils on the Built Development Area West and Preliminary Tier 1 Risk Assessment

Determinant Range of Tier 1 SSV WRAS Exceedance Exceedance Concentrations (mg/kg) Material of Tier 1 SSV of WRAS (mg/kg) Selection (sample Threshold Threshold number) Value Value

Total Arsenic 9.5-18.5 6351 50* 0 (25) 0*

Total Cadmium <0.5-2.4 2301 3 0 (25) 0

Total Chromium 39-75 30,4001,10 600 0 (25) 0

Total Lead 21-109 7502 500 0 (25) 0

1 Total Mercury (inorganic) <0.5-0.6 3,640 1 0 (25) -

Total Nickel 45-90 1,7901/ 1108 - 0 (25) -

Total Copper 36-84 71,7001/ 2008 - 0 (25) -

Total Zinc 70-251 665,0001/4504 - 0 (25) -

Total Selenium 1.2-2.9 13 0001 3 0 (25) 0

Boron (water soluble) <0.5-2.0 192,0001/34 - 0 (25) - pH (pH units) 5.9-7.6 5.5-8.53 <5 to >8 0 (25) 0

Total TPH C8-C35 <5.0 5005 50 0 (10) 0

Naphthalene <0.1 76.4^1 50 0 (20) 0

Acenaphthylene <0.1 86.1^1 50 0 (20) 0

Acenaphthene <0.1 57.0^1 50 0 (20) 0

Fluorene <0.1 30.9^1 50 0 (20) 0

Phenanthrene <0.1 21,9001 50 0 (20) 0

Anthracene <0.1 525,0001 50 0 (20) 0

Fluoranthene <0.1 22,6001 50 0 (20) 0

Pyrene <0.1 54,2001 50 0 (20) 0

Benzo(a)anthracene <0.1 89.51 50 0 (20) 0

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Chrysene <0.1 1371 50 0 (20) 0

Benzo(b)fluoranthene <0.1 1001 50 0 (20) 0

Benzo(k)fluoranthene <0.1 1411 50 0 (20) 0

Benzo (a) Pyrene <0.1 14.11 50 0 (20) 0

Indeno(1,2,3-cd)pyrene <0.1 601 50 0 (20) 0

Dibenzo(a,h)anthracene <0.1 12.71 50 0 (20) 0

Benzo(ghi)perylene <0.1 6541 50 0 (20) 0

PAH (EPA 16 total) <0.1 1005 50 0 (20) 0

TPH Aromatic C5-C7 <0.01 28.11,6 50 0 (5) 0

TPH Aromatic C7-C8 <0.01 869^1,7 50 0 (5) 0

TPH Aromatic C8-C10 <0.1 613^1 50 0 (5) 0

TPH Aromatic C10-C12 <0.1 364^1 50 0 (5) 0

TPH Aromatic C12-C16 <0.1 169^1 50 0 (5) 0

TPH Aromatic C16-C21 <0.1 28,2001 50 0 (5) 0

TPH Aromatic C21-C35 <0.1-3.0 28,0001 50 0 (5) 0

TPH Aliphatic C5-C6 <0.01 304^1 50 0 (5) 0

TPH Aliphatic C6-C8 <0.01 144^1 50 0 (5) 0

TPH Aliphatic C8-C10 <0.1 78^1 50 0 (5) 0

TPH Aliphatic C10-C12 <0.1 48^1 50 0 (5) 0

TPH Aliphatic C12-C16 <0.1 24^1 50 0 (5) 0

TPH Aliphatic C16-C21 <0.1 1,590,0001 50 0 (5) 0

TPH Aliphatic C21-C35 0.2-1.4 1,590,0001 50 0 (5) 0

Sum of TPH C6-C40 0.2-4.4 5005 50 0 (5) 0

Asbestos None Detected Detected/None - 0 (15) - Detected9

Benzene <0.01 28.11 - 0 (15) 0

Toluene <0.01 869^1 - 0 (15) 0

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Ethyl Benzene <0.01 518^1 0 (15) 0

m&p Xylene <0.01 576^1,P- - 0 (15) 0

o-xylene <0.01 478^1 - 0 (15) 0

Other VOC compounds <0.01 - - 0 (15) 0

Notes < - Value below laboratory limit of detection; * Wessex Water revised threshold for arsenic. Wessex Water Soil Survey Guidance P- - Assessment of combined concentrations of both m and p isomers, based on the lower Tier 1 concentration for p xylene. ^ In line with the EA approach in the published SGVs the GAC presented has been capped at the soil saturation limit. Internally derived SSV using CLEA v1.06 using all the same standard parameters that the Environment Agency used to derive standard SGVs for commercial and industrial end use with the exception the SOM has been set to 1%. DEFRA/EA (2002). R & D Publication SGV 10. Soil Guideline Values for Lead Contamination.

BS3882:2007 Specification for topsoil and requirements for use. Former ICRCL 59/83 (N.B Paper withdrawn by DEFRA in 2004) The Hazardous Waste (England and Wales) Regulations 2005. Inert Waste Threshold

Tier 1 screening criteria is based on if fibres are detected/none detected Chromium III values used for chromium SSV as 2009-2010 investigations on BDAE and BDAW have not identified any chromium VI above LOD (2 mg/kg) 13.3.25 The range of contaminant concentrations was found to be very low and is considered to be consistent with natural background concentrations in the locality and UK background concentrations. 13.3.26 The Phase 2 Supplementary Investigation (Ref. 13.8) was undertaken to assess the contamination status of the deeper site soils (>0.3 m bgl up to 5.0 m bgl) on the Built Development Area West and to enable further refinement of the PCSM. 13.3.27 Made Ground was encountered at one location Figure 13.2 extending to a depth of 0.33 m bgl. In all other trenches the materials encountered predominantly comprised superficial drift deposits and weathered bedrock. 13.3.28 A summary of the results is presented Table 13.3 and these results were used to conduct a Tier 1 risk assessment. Where appropriate, the analytical results were subject to statistical tests resulting in the 95th percentile (US95) Upper Confidence Level (UCL) of the true population mean (soils appeared typical of a single population) the UCL was then compared to the Tier 1 SSVs.

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Table 13.3: Summary of Chemical Analysis Results for Deeper Soils on the Built Development Area West and Tier 1 Risk Assessment

Determinant Range of UCL Concen- Tier 1 WRAS Exceedance of Exceedance Concen- tration SSV Material Tier 1 SSV of WRAS trations (natural soils mg/kg Selection (sample Threshold (mg/kg) only) (mg/kg) Threshold number) Value Value

Total Arsenic <5.0 – 31.3 16.8 6351 50* 0 (37) 0*

Total Cadmium <0.5 – 3.0 1.2 2301 3 0 (37) 0

Total Chromium 17 – 81 55.6 30,4001 600 0 (37) 0

Total Lead 10 – 140 39.2 7502 500 0 (37) 0

Total Mercury <0.5 NC 3,6401 1 0 (37) 0 (inorganic)

Total Nickel 25 – 71 52.4 1,7901/ - 0 (37) - 1108

Total Copper 25 – 179 64.5 71,7001/ - 0 (37) - 2008

Total Zinc 30 – 687 139.4 665,0001 - 0/1 (37) - /4504

Total Selenium 0.6 – 3.1 1.7 13,0001 3 0 (37) 1

Boron (water <0.5 – 5.1 1.6 192,0001 - 0/1 (37) - soluble) /34

pH (pH units) 7.5 – 8.5 8.1 5.5-8.53 <5 to >8 0 (37) 21

Total TPH C8- <0.5-72 31.8 5005 50 0 (14) 1 C35

Naphthalene <0.1 NC 76.4^1 50 0 (31) 0

Acenaphthylene <0.1 NC 86.1^1 50 0 (31) 0

Acenaphthene <0.1 NC 57.0^1 50 0 (31) 0

Fluorene <0.1 NC 30.9^1 50 0 (31) 0

Phenanthrene <0.1 NC 21,9001 50 0 (31) 0

Anthracene <0.1 NC 525,0001 50 0 (31) 0

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Fluoranthene <0.1 NC 22,6001 50 0 (31) 0

Pyrene <0.1 NC 54,2001 50 0 (31) 0

Benzo(a)anthra- <0.1 NC 89.51 50 0 (31) 0 cene

Chrysene <0.1 NC 1371 50 0 (31) 0

Benzo(b)fluoran <0.1 NC 1001 50 0 (31) 0 thene

Benzo(k)fluoran <0.1 NC 1411 50 0 (31) 0 thene

Benzo (a) <0.1 NC 14.11 50 0 (31) 0 Pyrene

Indeno(1,2,3- <0.1 NC 601 50 0 (31) 0 cd)pyrene

Dibenzo(a,h)ant <0.1 NC 12.71 50 0 (31) 0 hracene

Benzo(ghi)pery- <0.1 NC 6541 50 0 (31) 0 lene

PAH (EPA 16 <0.1 NC 1005 50 0 (31) 0 total)

TPH Aromatic <0.01 NC 28.11,6 50 0 (7) 0 C5-C7

TPH Aromatic <0.01 NC 869^1,7 50 0 (7) 0 C7-C8

TPH Aromatic <0.1 NC 613^1 50 0 (7) 0 C8-C10

TPH Aromatic <0.1 NC 364^1 50 0 (7) 0 C10-C12

TPH Aromatic <0.1 NC 169^1 50 0 (7) 0 C12-C16

TPH Aromatic <0.01 NC 28,2001 50 0 (7) 0 C16-C21

TPH Aromatic <0.1 – 2.0 2.0 28,0001 50 0 (7) 0 C21-C35

TPH Aliphatic <0.01 NC 304^1 50 0 (7) 0

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C5-C6

TPH Aliphatic <0.01 NC 144^1 50 0 (7) 0 C6-C8

TPH Aliphatic <0.1 NC 78^1 50 0 (7) 0 C8-C10

TPH Aliphatic <0.1 NC 48^1 50 0 (7) 0 C10-C12

TPH Aliphatic <0.1 – 0.1 0.14 24^1 50 0 (7) 0 C12-C16

TPH Aliphatic <0.1 – 0.2 0.19 1,590,00 50 0 (7) 0 C16-C21 01

TPH Aliphatic <0.1 – 2.4 1.88 1,590,00 50 0 (7) 0 C21-C35 01

Sum of TPH C6- <0.1 – 3.8 3.03 5005 50 0 (7) 0 C40

Asbestos None detected - Detected/ - 0 (3) - None Detected

Benzene <0.01 NC 28.11 - 0 (17) -

Toluene <0.01 NC 869^1 - 0 (17) -

Ethyl Benzene <0.01 NC 518^1 - 0 (17) -

m&p Xylene <0.01 NC 576^1,P- - 0 (17) -

o-xylene <0.01 NC 478^1 - 0 (17) -

Notes < - Value below laboratory limit of detection; * Wessex Water revised threshold for arsenic. Wessex Water Soil Survey Guidance

P- - Assessment of combined concentrations of both m and p isomers, based on the lower Tier 1 concentration for p xylene. ^ In line with the EA approach in the published SGVs the GAC presented has been capped at the soil saturation limit. Internally derived SSV using CLEA v1.06 using all the same standard parameters that the Environment Agency used to derive standard SGVs for commercial and industrial end use with the exception the SOM has been set to 1%. DEFRA/EA (2002). R & D Publication SGV 10. Soil Guideline Values for Lead Contamination. BS3882:2007 Specification for topsoil and requirements for use. Former ICRCL 59/83 (N.B Paper withdrawn by DEFRA in 2004)

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The Hazardous Waste (England and Wales) Regulations 2005. Inert Waste Threshold

Benzene Tier 1 Risk Assessment concentration for Aromatic TPH C5-C7. Toluene Tier 1 Risk Assessment for Aromatic TPH C7-C8 Statutory Instrument 1989 No 1263, ‘Sludge Use in Agriculture Regulations’ (1989), pH value >7. Tier 1 screening criteria is based on if fibres are detected/none detected Chromium III values used for chromium SSV as 2009-2010 investigations on BDAE and BDAW have not identified any chromium VI above LOD (2 mg/kg) 13.3.29 The range of contaminant concentrations is generally low and considered to be consistent with natural background concentrations on the locality and UK in general. 13.3.30 A number of exploratory holes were also undertaken to investigate the shallow made ground deposits in the area of former Benhole Farm and areas of possibly infilled ponds. The sampling locations are presented on Figure 13.2. 13.3.31 A summary of results are presented in Table 13.4: and have been used to conduct a Tier 1 risk assessment, by directly comparing concentrations with the assessment criteria. The results have been divided into samples of Made Ground and natural ground. Table 13.4: Summary of Chemical Analysis Results for Additional Locations on the Built Development Area West and Tier 1 Risk Assessment

Determinant Range of Range of Tier 1 SSV WRAS Exceedance Exceedance Concen Concen mg/kg Material of Tier 1 SSV of WRAS trations trations Selection (sample Threshold Made Natural Threshold number) Made Ground Ground Value Made Ground/ (mg/kg) (mg/kg) Ground/ Natural Natural Ground Ground

Total Arsenic 6.7-17.9 31.7-35.2 6351 50* 0 (4)/0 (2) 0/0

Total Cadmium 1.3-1.7 6.2-12.0 2301 3 0 (4)/0 (2) 0/2

Total Chromium 33-53 41-42 30,4001 600 0 (4)/0 (2) 0/0 (III)

Hexavalent <2 <2 351 - 0 (3)/0 (2) 0/0 Chromium

Total Lead 36-100 129-165 7502 500 0 (4)/0 (2) 0/0

Total Mercury <0.5 <0.5 3,6401 1 0 (4)/0 (2) 0/0 (inorganic)

Total Nickel 32-59 31-31 71,7001/20 - 0 (4)/0 (2) 0/0 08

Total Copper 30-67 24-29 1,7901/110 - 0 (4)/0 (2) 0/0 8

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Total Zinc 146-446 276-336 665,0001/4 - 0 (4)/0 (2) 0/0 508

Total Selenium 0.6-0.9 <0.5 13,0001 3 0 (4)/0 (2) 0/0

Boron (water 1.0-2.1 <0.5 192,0001/3 - 0 (3)/ 0/0 soluble) 4 0 (2)

pH (pH units) 7.8-8.0 8.3 5.5 – 8.53 <5 or >8 0 (3)/(2) 0/2

Total Sulphate <0.05 - 0.249 0.20 0 (2)/(0) 0/0 (%SO4)

Total Cyanide <1-3.1 - 16,000FC,1 25FC 0 (2)/(0) 0/0

Sulphide <2 - 2504 250 0 (2)/(0) 0/0

Elemental Sulphur <10 - 50004 5000 0 (2)/(0) 0/0

Total Phenol <1 - 3200P,1 5 0 (2)/(0) 0/0

Total TPH C8-C35 <5 - 5005 50 0 (2)/(0) 0/0

Soil Organic 1.2 0.3-0.5 - - (1)/(3) - Matter

Naphthalene <0.1 <0.1 76.41 50 0 (2)/0 (1) 0/0

Acenaphthylene <0.1 <0.1 86.1^1 50 0 (2)/0 (1) 0/0

Acenaphthene <0.1 <0.1 57.0^1 50 0 (2)/0 (1) 0/0

Fluorene <0.1 <0.1 30.9^1 50 0 (2)/0 (1) 0/0

Phenanthrene <0.1 <0.1 21,9001 50 0 (2)/0 (1) 0/0

Anthracene <0.1 <0.1 525,0001 50 0 (2)/0 (1) 0/0

Fluoranthene <0.1 <0.1 22,6001 50 0 (2)/0 (1) 0/0

Pyrene <0.1 <0.1 54,2001 50 0 (2)/0 (1) 0/0

Benzo(a)anthrace <0.1 <0.1 89.51 50 0 (2)/0 (1) 0/0 ne

Chrysene <0.1 <0.1 1371 50 0 (2)/0 (1) 0/0

Benzo(b)fluoranth <0.1 <0.1 1001 50 0 (2)/0 (1) 0/0 ene

Benzo(k)fluoranth <0.1 <0.1 1411 50 0 (2)/0 (1) 0/0 ene

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Benzo (a) Pyrene <0.1 <0.1 14.11 50 0 (2)/0 (1) 0/0

Indeno(1,2,3- <0.1 <0.1 601 50 0 (2)/0 (1) 0/0 cd)pyrene

Dibenzo(a,h)anthr <0.1 <0.1 12.71 50 0 (2)/0 (1) 0/0 acene

Benzo(ghi)perylen <0.1 <0.1 6541 50 0 (2)/0 (1) 0/0 e

PAH (EPA 16 total) <0.1 <0.1 1005 50 0 (2)/0 (1) 0/0

Asbestos None - Detected/N - 0 (1)/(0) - detected one Detected10

* Wessex Water revised threshold for arsenic. Wessex Water Soil Survey Guidance FC – Based on the value for Free cyanide as no total screening value exists

TP – Based on the Total Phenol concentration P _ Based on the Phenol concentration ^ - In line with the EA approach in the published SGVs, the GAC presented has been capped at the soil saturation limit. ~ - Statistical outliers have been retained in the dataset as these values are not considered to represent a separate population.

ND- None detected NC – Not Calculated 1. Internally Derived AMEC SSV using CLEA model v1.06 using all the same standard input parameters that the Environment Agency used to derive standard SGVs for commercial and industrial end use with the exception that SOM has been set to 1 %. 2. Environment Agency (2002) R & D Publication SGV 10. Soil Guideline Values for Lead Contamination

3. BS3882:2007 Specification for Topsoil and requirements for use. 4. Former ICRCL Guidance Note 59/83 (N.B. paper withdrawn by DEFRA in 2004) 5. The Hazardous Waste (England and Wales) Regulations 2005. Inert Waste Threshold 6. Benzene Tier 1 Risk Assessment concentration used for Aromatic TPH C5-C7 7. Toluene Tier 1 Risk Assessment concentration used for Aromatic TPH C7-C8 8. Statutory Instrument 1989 No. 1263, ’Sludge (Use in Agriculture) Regulations 1989’, pH value >7.0

9. BRE Special Digest SD1 Specification (3rd Edition, 2005) 10. Tier 1 Assessment for asbestos is based on if fibres are detected or none detected 13.3.32 Overall the intrusive investigations of soils within the Built Development Area West have identified the risk of significant non-radiological contamination being present as very low.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 23 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land Built Development Area East 13.3.33 The Desk Based Assessment for the Complementary (Adjacent) Lands indicates that limited contamination sampling and monitoring has been conducted within the Built Development Area East. 13.3.34 A report prepared by Serco (2006) (Ref. 13.10) relates to a baseline contamination investigation for an area of land which was to be used for the temporary storage of spoil arising from the construction of a new Intermediate Level Waste (ILW) storage site for Hinkley Point A. This investigation generally found low levels of soil contamination, although very occasional isolated suspected asbestos containing materials were identified within the proposed spoil disposal area. The ‘pre-closure’ report (i.e. a survey undertaken after the soils temporarily stored here had been removed) prepared by Serco for this area found concentrations of contaminants consistent with the baseline survey and no asbestos containing materials were identified. 13.3.35 A number of potential sources of contamination have been identified within the Built Development Area East including a former sewage treatment works, waste disposal, Made Ground deposits, a former construction/accommodation camp and fabrication area with associated boiler houses, fuel oil storage tanks and electrical substations. In addition the desk study identified the theoretical potential for radionuclides from routine authorised discharges from Hinkley Point to be present and a limited potential for contaminants present in the soils and groundwater beneath the Hinkley Point A and B Power Stations to have migrated onto the Built Development Area East. 13.3.36 Intrusive investigations as part of the Preliminary Phase 2 Contamination Assessment (Non Radiological) were undertaken of the Built Development Area East (Ref. 13.8) between November 2009 and February 2010. The investigations are still ongoing therefore the information presented is preliminary in nature and will be updated when the scheduled works are complete. 13.3.37 Investigations identified the presence of variable depths of made ground across the BDAE, ranging from absent to a proven depth of 9.0 m (GB4) within the mounds. Made Ground deposits have been found to typically comprise either reworked natural soils (weathered Blue Lias formation deposits comprising mudstone and limestone), or demolition and construction waste materials. Natural superficial (drift) deposits have only been rarely encountered within the BDAE, having been identified in DBH2_23, GB6 and TE61. Apparent sediment deposits (believed to be associated with former infilled ponds) were also identified within TE13 and Tr2_5. 13.3.38 Natural Blue Lias deposits (bedrock) have been proven at depths ranging from 0.1 mbgl (DBH2_24) and 9.0 mbgl (GB4). These deposits comprise an interbedded sequence of mudstone and limestone units. The upper mudstone units were frequently noted to have been significantly weathered to a clay like deposit. Further details of the ground conditions encountered are presented within the Preliminary Phase 2 Contamination Assessment report and within the following sections. 13.3.39 A summary of the results is presented in Table 13.4 and Table 13.6: these results were used to conduct a Tier 1 risk assessment. Were appropriate the analytical results were subject to statistical tests resulting in the 95th Upper Confidence Level (UCL) of the true population mean for each contaminant being compared to the Critical Concentrations (Tier 1 SSVs) to determine whether the site soils may pose a risk to human health in the context of a commercial/industrial end use. For the purpose of this statistical analysis the data was treated as belonging to two main ‘populations’ (in statistical terms), made ground and natural ground, and grouped by geographical area, with the exception of Area 3 which contained a significant thickness of made

24 | HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2

ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land ground and as such was separated into three separate made ground populations. The range of UCL values calculated for the Built Development Area East are presented in Table 13.4 and Table 13.5. Table 13.5: Summary of Chemical Analysis Results for Made Ground Soils on the Built Development Area East and Tier 1 Risk Assessment

Determinand Range of UCL Tier 1 WRAS Exceedance Exceedance Concentrations Concen- SSV Material of Tier 1 of WRAS (mg/kg) tration mg/kg Selection SSV Threshold Ranges Threshold (sample Value (natural Value number) soils) (mg/kg)

Total Arsenic <5–20 11.5-18.4 6351 50* 0 (129) 0

Total Cadmium <0.5–3 1.1-1.6 2301 3 0 (129) 0

Total Chromium (III) 12-78 29.8-56.5 30,4001 600 0 (129) 0

Hexavalent <2 1 351 - 0 (129) - Chromium

Total Lead 6-382 24.8-167.8 7502 500 0 (129) 0

Total Mercury <0.5 0.25 3,6401 1 0 (129) 0

Total Copper 7-241 45.4-173.8 71,7001/ - 0/1(129) - 2008

Total Nickel 6-87 35.3-76.6 1,7901/1 - 0/0 (129) - 108

Total Zinc 22-922 101.3-605.3 665,0001 - 0/2 (129) - /4508

Total Selenium <0.5-3.9 1.2-3.1 13,0001 3 0 (129) 8

Boron (water <0.5-3.6 1-3.3 192,0001 - 0/2 (129) - soluble) /34 pH (pH units) 6.9-11.4 NC 5.5 – <5 or >8 25 (129) 67 8.53

Total Sulphate <0.05-0.53 0.08-0.34 0.249 0.20 15 (129) 16 (%SO4)

Total Cyanide <1-5.4 0.5-2.1 16,000FC, 25FC 0 (129) 0 1

Sulphide <2-163 1-141.3 2504 250 0 (129) 0

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 25 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

Elemental Sulphur <10-1526 5-1363.8 50004 5000 0 (129) 0

Total Phenol <1-3 0.5-1.2 3200P,1 5 0 (129) 0

Asbestos ND-Fibres - ND/Dete - 12 (140) - Detected cted10

Total Petoleum <5-157 2.5-114.2 5005 50 0 (94) 12

Hydrocarbons (C8-

C35)

PAH (EPA 16 total) <0.1-226.7 0.1-175.0 1005 50 0 (129) 3

Naphthalene <0.1-0.5 0.1-0.4 76.41 50 0 (129) 0

Acenaphthylene <0.1-1.8 0.1-0.9 86.1^1 50 0 (129) 0

Acenaphthene <0.1-2.5 0.1-1.9 57.0^1 50 0 (129) 0

Fluorene <0.1-2.8 0.1-2.1 30.9^1 50 0 (129) 0

Phenanthrene <0.1-28.3 0.1-21.7 21,9001 50 0 (129) 0

Anthracene <0.1-7.5 0.1-5.8 525,0001 50 0 (129) 0

Fluoranthene <0.1-43.4 0.1-33.5 22,6001 50 0 (129) 0

Pyrene <0.1-30.8 0.1-23.8 54,2001 50 0 (129) 0

Benzo(a)Anthracen <0.1-17.3 0.1-13.4 89.51 50 0 (129) 0 e

Chrysene <0.1-18.2 0.1-14.1 1371 50 0 (129) 0

Benzo(b)Fluoranthe <0.1-16.6 0.1-12.9 1001 50 0 (129) 0 ne

Benzo(k)Fluoranthe <0.1-12.9 0.1-10.0 1411 50 0 (129) 0 ne

Benzo (a) Pyrene <0.1-16.5 0.1-12.8 14.11 50 1 (129) 0

Indeno(1,2,3- <0.1-13.5 0.1-10.5 601 50 0 (129) 0 cd)Pyrene

Dibenzo(a,h)Anthra <0.1-3.1 0.1-2.4 12.71 50 0 (129) 0 cene

Benzo(ghi)perylene <0.1-11.8 0.1-9.2 6541 50 0 (129) 0

TPH Aromatic C5-C7 <0.01 0.01 28.11,6 50 0 (40) 0

TPH Aromatic C7-C8 <0.01 0.01 869^1,7 50 0 (40) 0

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

TPH Aromatic C8- <0.1-0.2 0.1 613^1 50 0 (40) 0 C10

TPH Aromatic C10- <0.1-0.1 0.1 364^1 50 0 (40) 0 C12

TPH Aromatic C12- <0.1-1.9 0.1-1.0 169^1 50 0 (40) 0 C16

TPH Aromatic C16- <0.1-10.6 0.7-6.2 28,2001 50 0 (40) 0 C21

TPH Aromatic C21- <0.1-106.8 2.7-145.1 28,2001 50 0 (40) 5 C35

TPH Aliphatic C5-C6 <0.01 0.01 304^1 50 0 (40) 0

TPH Aliphatic C6-C8 <0.01 0.01 144^1 50 0 (40) 0

TPH Aliphatic C8- <0.1-0.4 0.1-0.4 78^1 50 0 (40) 0 C10

TPH Aliphatic C10- <0.1-0.3 0.1-0.3 48^1 50 0 (40) 0 C12

TPH Aliphatic C12- <0.1-2.7 0.4-2.5 24^1 50 0 (40) 0 C16

TPH Aliphatic C16- <0.1-15.1 1.4-7.5 1,590,00 50 0 (40) 0 C21 01

TPH Aliphatic C21- <0.1-257.8 2.6-114.5 1,590,00 50 0 (40) 2 C35 01

Total TPH (Sum C6- <0.1-377.2 9.6-204.6 5005 50 0 (40) 8 C40)

Benzene <0.01 NC 28.11 - 0 (38) -

Toluene <0.01 NC 869^1 - 0 (38) -

Ethyl Benzene <0.01 NC 518^1 - 0 (38) - m&p Xylene <0.01 NC 576^P-1 - 0 (38) - o-xylene <0.01 NC 478^1 - 0 (38) -

Other VOCs <0.01-0.27 NC - - (38) -

All SVOC <0.01-8.04 NC - - (30) -

PCBs (7 congeners) <0.01 NC 40 (total - 0 (16) -

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 27 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

PCBs)

* Wessex Water revised threshold for arsenic. Wessex Water Soil Survey Guidance

FC – Based on the value for Free cyanide as no total screening value exists TP – Based on the Total Phenol concentration P _ Based on the Phenol concentration

P- -Assessment of the combined concentrations of both m and p isomers, based on the lower Tier 1 concentration for p xylene. ^ - In line with the EA approach in the published SGVs, the GAC presented has been capped at the soil saturation limit. ~ - Statistical outliers have been retained in the dataset as these values are not considered to represent a separate population. ND- None detected NC – Not Calculated 1. Internally Derived AMEC SSV using CLEA model v1.06 using all the same standard input parameters that the Environment Agency used to derive standard SGVs for commercial and industrial end use with the exception that SOM has been set to 1 %. 2. Environment Agency (2002) R & D Publication SGV 10. Soil Guideline Values for Lead Contamination

6. Benzene Tier 1 Risk Assessment concentration used for Aromatic TPH C5-C7 7. Toluene Tier 1 Risk Assessment concentration used for Aromatic TPH C7-C8 8. Statutory Instrument 1989 No. 1263, ’Sludge (Use in Agriculture) Regulations 1989’, pH value >7.0

9. BRE Special Digest SD1 Specification (3rd Edition, 2005) 10. Tier 1 Assessment for asbestos is based on if fibres are detected or none detected

Table 13.6: Summary of Chemical Analysis Results for Natural Soils on the Built Development Area East and Tier 1 Risk Assessment

Determinand Range of UCL Tier 1 WRAS Exceedance Exceedance Concentrations Concentration SSVmg/kg Material of Tier 1 SSV of WRAS (mg/kg) Ranges Selection (sample Threshold (natural soils) Threshold number) Value (mg/kg) Value

Total Arsenic <5-18.7 8.8-16.2 6351 50* 0 (42) 0

Total Cadmium <0.5-2.2 0.8-1.2 2301 3 0 (42) 0

Total Chromium 21-58 37.6-55.1 30,4001 600 0 (42) 0

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Hexalvalent <2 1 351 - 0 (42) - Chromium

Total Lead <1-53 14.7-48.7 7502 500 0 (42) 0

Total Mercury <0.5 0.25 3,6401 1 0 (42) 0

Total Copper 23-72 37.1-63.9 71,7001/200 - 0/0 (42) - 8

Total Nickel 24-78 39.9-58.1 1,7901/1108 - 0/0 (42) -

Total Zinc 25-115 65.9-143.2 665,0001/45 - 0/0 (42) - 08

Total Selenium <0.5-3.6 1.0-2.6 13,0001 3 0 (42) 2

Boron (water <0.5-4.2 0.8-5.3 192,0001/34 - 0/1 (42) 0 soluble) pH (pH units) 7.4-8.9 NC 5.5 – 8.53 <5 or >8 2 (42) 32

Total Sulphate <0.05-0.37 0.025-0.41 0.249 0.20 2 (42) 3 (%SO4)

Total Cyanide <1-2 0.5-2.1 16,000f1c 25FC 0 (42) 0

Sulphide <2-17.4 1.0-15.9 2504 250 0 (42) 0

Elemental Sulphur <10-14 5-15 50004 5000 0 (42) 0

Total Phenol <1 0.5 3200P 5 0 (42) 0

Asbestos ND - ND/ - 0 (17) - Detected

Total Petoleum <5-5 2.5-3.5 5005 50 0 (37) 0

Hydrocarbons (C8-

C35)

PAH (EPA 16 total) <0.1-1.8 0.1-2.0 1005 50 0 (42) 0

Naphthalene <0.1-0.1 0.1 76.41 50 0 (42) 0

Acenaphthylene <0.1 0.1 86.1^1 50 0 (42) 0

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 29 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

Acenaphthene <0.1-0.2 0.1 57.0^1 50 0 (42) 0

Fluorene <0.1 0.1 30.9^1 50 0 (42) 0

Phenanthrene <0.1-0.1 0.1 21,9001 50 0 (42) 0

Anthracene <0.1-2.0 0.1-0.7 525,0001 50 0 (42) 0

Fluoranthene <0.1-0.7 0.1-0.3 22,6001 50 0 (42) 0

Pyrene <0.1-0.1 0.1 54,2001 50 0 (42) 0

Benzo(a)Anthrace <0.1-0.1 0.1 89.51 50 0 (42) 0 ne

Chrysene <0.1-0.1 0.1 1371 50 0 (42) 0

Benzo(b)Fluoranth <0.1-0.1 0.1 1001 50 0 (42) 0 ene

Benzo(k)Fluoranth <0.1-0.3 0.1-0.3 1411 50 0 (42) 0 ene

Benzo (a) Pyrene <0.1-0.8 0.1-0.5 14.11 50 0 (42) 0

Indeno(1,2,3- <0.1-0.5 0.1-0.4 601 50 0 (42) 0 cd)Pyrene

Dibenzo(a,h)Anthr <0.1-0.1 0.1-0.1 12.71 50 0 (42) 0 acene

Benzo(ghi)perylen <0.1-1.0 0.1-0.9 6541 50 0 (42) 0 e

TPH Aromatic C5- <0.01 NC 28.11,6 50 0 (5) 0 C7

TPH Aromatic C7- <0.01 NC 869^1,7 50 0 (5) 0 C8

TPH Aromatic C8- <0.1 NC 613^1 50 0 (5) 0 C10

TPH Aromatic C10- <0.1 NC 364^1 50 0 (5) 0 C12

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

TPH Aromatic C12- <0.1 NC 169^1 50 0 (5) 0 C16

TPH Aromatic C16- <0.1-0.2 NC 28,2001 50 0 (5) 0 C21

TPH Aromatic C21- <0.1-0.4 NC 28,2001 50 0 (5) 0 C35

TPH Aliphatic C5- <0.01 NC 304^1 50 0 (5) 0 C6

TPH Aliphatic C6- <0.01 NC 144^1 50 0 (5) 0 C8

TPH Aliphatic C8- <0.1-0.1 NC 78^1 50 0 (5) 0 C10

TPH Aliphatic C10- <0.1 NC 48^1 50 0 (5) 0 C12

TPH Aliphatic C12- <0.1-0.3 NC 24^1 50 0 (5) 0 C16

TPH Aliphatic C16- <0.1-0.3 NC 1,590,0001 50 0 (5) 0 C21

TPH Aliphatic C21- <0.1-1.1 NC 1,590,0001 50 0 (5) 0 C35

Total TPH (Sum 0.6-1.9 NC 5005 50 0 (5) 0 C6-C40)

Benzene <0.01 NC 28.11 - 0 (2) -

Toluene <0.01 NC 869^1 - 0 (2) -

Ethyl Benzene <0.01 NC 518^1 - 0 (2) - m&p Xylene <0.01 NC 576^P-1 - 0 (2) - o-xylene <0.01 NC 478^1 - 0 (2) -

Other VOCs <0.01 NC - - 0 (2) -

All SVOC <0.01 NC - - 0 (3) -

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 31 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

PCBs (7 <0.01 NC 40 (total - 0 (4) - congeners) PCBs)

* Wessex Water revised threshold for arsenic. Wessex Water Soil Survey Guidance FC – Based on the value for Free cyanide as no total screening value exists TP – Based on the Total Phenol concentration P _ Based on the Phenol concentration P- -Assessment of the combined concentrations of both m and p isomers, based on the lower Tier 1 concentration for p xylene. ^ - In line with the EA approach in the published SGVs, the GAC presented has been capped at the soil saturation limit. ~ - Statistical outliers have been retained in the dataset as these values are not considered to represent a separate population. ND- None detected NC – Not Calculated

1. Internally Derived AMEC SSV using CLEA model v1.06 using all the same standard input parameters that the Environment Agency used to derive standard SGVs for commercial and industrial end use with the exception that SOM has been set to 1 %.

2. Environment Agency (2002) R & D Publication SGV 10. Soil Guideline Values for Lead Contamination 3. BS3882:2007 Specification for Topsoil and requirements for use. 4. Former ICRCL Guidance Note 59/83 (N.B. paper withdrawn by DEFRA in 2004)

5. The Hazardous Waste (England and Wales) Regulations 2005. Inert Waste Threshold 6. Benzene Tier 1 Risk Assessment concentration used for Aromatic TPH C5-C7 7. Toluene Tier 1 Risk Assessment concentration used for Aromatic TPH C7-C8 8. Statutory Instrument 1989 No. 1263, ’Sludge (Use in Agriculture) Regulations 1989’, pH value >7.0 9. BRE Special Digest SD1 Specification 10. Tier 1 Assessment for asbestos is based on if fibres are detected or none detected Asbestos containing materials 13.3.40 Suspected asbestos containing materials (ACM) have been identified at six locations in Area 3, ten locations in Area 4 and five locations on Area 5 within the Built Development Area East. Figure 13.9 shows the occurrence of suspected and confirmed ACMs identified during the site investigation works. ACMs (by laboratory testing) have been identified in seven of the above locations as both competent, cemented materials (asbestos cement) and as fibrous lagging and insulation materials. The presence of ACMs appears to be associated with the occurrence of construction and demolition waste materials. The analysis of the fifteen soil samples targeting ACMs or suspected ACMs and other soil samples from elsewhere on the Built Development Area

32 | HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2

ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land East which were screened for asbestos, fibres have not been found above 0.01%w/w (some analytical results for asbestos analysis are still outstanding). Waste Acceptance Criteria 13.3.41 Waste acceptance criteria (WAC) analysis has been scheduled on twenty samples from the Built Development Area East. All samples were of made ground material with the exception of two samples of natural ground materials (weathered Blue Lias mudstone in TE12 and apparent pond sediment in TE13). 13.3.42 Table 13.7 below provides a summary of the WAC results across the Built Development Area East and highlights any exceedances of the Waste Acceptance Criteria. Table 13.7: Summary of Waste Acceptance Criteria Analysis and Comparison with Waste Acceptance Criteria

Determinand Range Of Inert Waste Stable Hazardous Concentrations Landfill Non-reactiven Waste Landfill (mg/kg Unless (Number Of Hazardous (Number Of Stated) Exceedences In Waste In Exceedences In Bold) Non-Hazardous Bold) Landfill (Number Of Exceedences In Bold)

Solid Waste Analysis

TOC (%) 0.4-2.8 3 5 6

Loss on Ignition (%) 2.9-9.4 -- -- 10

BTEX (mg/kg) <0.01 6 -- --

Sum of PCBs (mg/kg) <0.01-0.02 1 -- --

Mineral Oil (mg/kg) 1-136 500 -- --

Total PAH (mg/kg) <0.1-41.1 100 -- --

pH (Units) 7.3-10.6 ------

Acid Neutralisation <0.1 -- To be evaluated To be evaluated Capacity (mol/kg)

Eluate Analysis Limit values for compliance leaching test using BS EN 12457-3 at L/S 10 l/kg (mg/kg)

Arsenic <0.1 0.5 2 25

Barium <0.1-0.1 20 100 300

Cadmium <0.01 0.04 1 5

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 33 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

Chromium <0.1 0.5 10 70

Copper <0.1 2 50 100

Mercury <0.001 0.01 0.2 2

Molybdenum <0.1-2.7 0.5 (5) 10 30

Nickel <0.1 0.4 10 40

Lead <0.1 0.5 10 50

Antimony <0.01 0.06 0.7 5

Selenium <0.01 0.1 0.5 7

Zinc <0.1 4 50 200

Chloride 5-82 800 15000 25000

Fluoride <1 10 150 500

Sulphate 2-3335 1000 (3) 20000 50000

TDS 143-2508 4000 60000 100000

Phenol Index <0.5 1 - -

DOC 32-110 500 800 1000

Leachate Test Information

pH (units) 7.4-8.0 - - -

Electrical Conductivity 136-2480 - - -

If no value is presented in brackets then no samples exceeded the screening criteria for that contaminant. Southern Construction Phase Area 13.3.43 To date, no intrusive investigations have been undertaken on the Southern Construction Phase Area. However, given the historical land use and the very low density of salient features with which potential contamination could be associated, it is considered that the risk of this area being significantly contaminated is very low. Nevertheless, limited intrusive investigations, including targeting areas of infilled historical ponds, are planned to allow confirmation of the contamination status. iii) Radiological surveys of ground conditions Built Development Area West 13.3.44 A series of assessments relating to the radiological conditions on the Built Development Area West have been undertaken. A summary of the results, including data from both the initial survey surface samples and the deeper Phase 2 investigations, is presented in Table 13.8. The Table includes ranges of results and an indication of where results have exceeded screening

34 | HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2

ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land values. The results were also compared with adopted background values derived from a number of sources. Environmental monitoring data relating to the Hinkley site have been used where available, otherwise data relating more generally to the United Kingdom have been used. Table 13.9 summarises the background data used and the associated data sources.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 35 ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land

Table 13.8: Summary of Radiochemical Soil Analysis Results for Built Development Area West

Determinand Activity Concentration Adopted Exceedance Of Rangea/Bq g-1 Screening Adopted Screening l b l Ac-228 0.0168 - 0.1066 0.19 0 (50)

Ag-110m < 0.00042 - < 0.0023 N/A N/A

Be-7 < 0.0028 - < 0.024 N/A N/A

Bi-212 0.023 - 0.087 N/A N/A

Bi-214 0.0224 - 0.082 N/A N/A

C-14 < 0.0020 - 0.0040 N/A N/A

Ce-144 < 0.0019 - < 0.0064 N/A N/A

Co-57 < 0.00031 - < 0.00085 N/A N/A

Co-58 < 0.00019 - < 0.0027 N/A N/A

Co-60 < 0.00037 - < 0.0097 N/A N/A

Cs-134 < 0.00041 - < 0.0020 N/A N/A

Cs-137 0.00263 - 0.0106 N/A N/A

Eu-152 < 0.00091 - < 0.016 N/A N/A

Eu-154 < 0.00056 - < 0.0023 N/A N/A

Eu-155 < 0.0023 - < 0.0089 N/A N/A

I-131 < 0.00026 - < 0.0028 N/A N/A

K-40 0.264 - 2.17 N/A N/A

Mn-54 < 0.00035 - < 0.0026 N/A N/A

Nb-95 0 - < 0.0018 N/A N/A

Np-237 < 0.0029 - < 0.015 N/A N/A

Pa-233 < 0.00042 - < 0.0057 N/A N/A

Pa-234m < 0.058 - 0.142 0.12 1 (50)e

Pb-210 0.017- 0.073 0.19 0 (50)

Pb-212 0.0156 - 0.0852 0.19 0 (50)

Pb-214 0.0200 - 0.0834 0.19 0 (50)

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Ra-226 0.021 - 0.140 0.093 2 (50)e

Ru-106 < 0.0028 - < 0.032 N/A N/A

Sb-125 < 0.00063 - < 0.0087 N/A N/A

Th-234 0.026 - 0.12 0.43 0 (50)

Tl-208 0.0064 - 0.0291 N/C N/A

U-235 0.00099 - 0.0054 3.7 0 (50)

Zn-65 < 0.00095 - < 0.0065 N/A N/A

Zr-95 < 0.00033 - < 0.0042 N/A N/A

Gross alpha (calibrated with 0.282 - 0.84 N/A N/A

Gross beta (calibrated with K- 0.306 - 1.47 N/A N/A 40) Tritium 0.038 - 0.152 N/A N/A

aWhere positive values, i.e. detected values, have been reported, these have been used in preference to “less than” (<) values for presenting the ranges of activity concentration. bThe adopted screening values are derived from the values for the Schedule 1 elements listed in the Radioactive Substances Act 1993. The screening values are calculated by dividing the Schedule 1 elemental limit by the number of isotopes of the radionuclides in the natural radioactive decay series (uranium-238, thorium-232 and uranium-235). c N/A indicates not applicable.

d Only positive values are used for assessment of numbers of results that exceed screening values. “Less than” values that exceed the screening values are not included. e Although the adopted screening value was exceeded, the Schedule 1 elemental limit described in the Radioactive Substances Act 1993 was not.

Table 13.9: Adopted Background Values

Determinand Background Value/Bq g-1

C-14* 0.010 - 0.012 (0.011)

Co-60* < 0.00023 - < 0.00041 (< 0.00032)

Zr-95* < 0.00090 - < 0.0035 (< 0.0022)

Nb-95* < 0.0010 - < 0.0072 (< 0.0041 )

Ru-106* < 0.0025 - < 0.0049 (< 0.0037)

Sb-125* < 0.00069 - < 0.0012 (< 0.0009)

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Determinand Background Value/Bq g-1

Cs-134* < 0.00034 - < 0.00064 (< 0.00049)

Cs-137* 0.0052 - 0.0068 (0.0060)

Ce-144* < 0.0020 - < 0.0038 (< 0.0029)

Eu-154* < 0.00071 - < 0.0013 (< 0.0010)

Eu-155* < 0.00094 - < 0.0018 (< 0.0014)

Am-241* < 0.00097 - < 0.0026 (< 0.0018)

K-40# 0 - 3.2

Pb-210# 0.041

Ra-226+ 0.037

Values in parentheses are mean values *Data from RIFE reports 13 and 14.

# Data from DoE/HMIP/RR/93/063 (1993). + Data from UNSCEAR (2000). Built Development Area East 13.3.45 Similarly to the Built Development Area West, a series of assessments relating to the radiological conditions on the Built Development Area East have been undertaken. 13.3.46 A non-intrusive radiological survey, including a radiological walkover survey and environmental gamma dose rate measurements, was undertaken in December 2009 prior to the commencement of intrusive works. The survey locations are presented in Figure 13.5b. 13.3.47 In general, the walkover survey recorded measurements that were low, being at or below expected background values for the area. The environmental gamma dose rates measured were also generally consistent with background levels. The radiological survey did however identify an area of elevated radiation readings close to the eastern boundary of the Built Development Area East land adjacent to the nuclear licensed site. The signature of recorded measurements suggested that shine from a radiation source inside the Hinkley Point A site boundary may be responsible for the elevated readings. The annual dose in excess of background based on commercial occupancy of the most elevated location would be 0.071 mSv a-1 based on external radiation only. This constitutes 7.1% of the annual dose limit for members of the public (1 mSv a-1), and is 23.8 % of the dose constraint adopted by the Environment Agency (0.3 mSv a-1) in their contaminated land guidance (Ref. 13.11). 13.3.48 A summary of the results from the Phase 2 intrusive works, including a comparison with adopted screening values, where available, is presented in Table 13.10. The results were also compared with the adopted background values described in Table 13.9. In addition, the gross alpha beta results were compared with those obtained for the Built Development West land for consistency between the two datasets. The results given are for the 68 samples that have been analysed to date.

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Table 13.10: Summary of Radiochemical Soil Analysis Results for the Built Development Area East

Determinand Activity concentration Adopted Exceedance of Rangea/Bq g-1 Screening Adopted valueb/Bq g-1 Screening Value (Sample Number)c

C-14 0.0032 - 0.0143 N/Ad N/A

Ac-228 0.0201 - 0.0539 0.19 0 (68 )

Ag-110m < 0.00043 - < 0.0015 N/A N/A

Am-241 0.0025 - < 0.0043 N/A N/A

Be-7 < 0.0022 - < 0.026 N/A N/A

Bi-212 0.017 - 0.060 N/A N/A

Bi-214 0.0191 - 0.094 N/A N/A

Ce-144 < 0.0025 - < 0.0073 N/A N/A

Co-57 < 0.00030 - < 0.0011 N/A N/A

Co-58 < 0.00024 - < 0.0025 N/A N/A

Co-60 < 0.00027 - < 0.0040 N/A N/A

Cs-134 < 0.0023 - < 0.0019 N/A N/A

Cs-137 0.00088 - 0.0093 N/A N/A

Eu-152 < 0.0082 - < 0.020 N/A N/A

Eu-154 < 0.0062 - < 0.0023 N/A N/A

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Eu-155 < 0.0016 - < 0.0062 N/A N/A

I-131 < 0.00047 - < 0.0027 N/A N/A

K-40 0.321 - 0.794 N/A N/A

Mn-54 < 0.00028 - < 0.0037 N/A N/A

Nb-95 < 0.00033 - < 0.0020 N/A N/A

Np-237 < 0.003 - < 0.0092 N/A N/A

Pa-233 < 0.00065 - < 0.0052 N/A N/A

Pa-234m < 0.064 - < 0.26 0.12 0 (68)

Pb-210 0.020 - 0.063 0.19 0 (68)

Pb-212 0.0178 - 0.0489 0.19 0 (68)

Pb-214 0.0201 - 0.0837 0.19 0 (68)

Ra-226 0.018 - 0.090 0.093 0 (68)

Ru-106 < 0.0020 - < 0.037 N/A N/A

Sb-125 < 0.00088 - < 0.0077 N/A N/A

Th-234 0.026 - 0.091 0.43 0 (68)

Tl-208 0.0062 - 0.0165 N/C N/A

U-235 0.00086 - 0.00437 3.7 0 (68)

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Zn-65 < 0.0012 - < 0.0044 N/A N/A

Zr-95 < 0.00052 - < 0.0047 N/A N/A

Gross alpha (calibrated with 0.294 - 0.91 N/A N/A Am-241)

Gross beta (calibrated with K- 0.361 - 1.014 N/A N/A 40)

Total tritium < 0.011 - < 0.047 N/A N/A

aWhere positive values, i.e. detected values, have been reported, these have been used in preference to “less than” (<) values for presenting the ranges of activity concentration.

bThe adopted screening values are derived from the values for the Schedule 1 elements listed in the Radioactive Substances Act 1993. The screening values are calculated by dividing the Schedule 1 elemental limit by the number of isotopes of the radionuclides in the natural radioactive decay series (uranium-238, thorium-232 and uranium-235). c N/A indicates not applicable. d Only positive values are used for assessment of numbers of results that exceed screening values. “Less than” values that exceed the screening values are not included. Southern Construction Phase Area 13.3.49 A non intrusive radiological survey comprising environmental gamma dose rate measurements, was undertaken in October 2009 prior to the commencement of intrusive investigations. The survey locations are presented on Figure 13.6. 13.3.50 The environmental gamma dose rates measured on the Southern Construction Phase Area were consistent with background levels. 13.3.51 As part of the intrusive works planned on the Southern Construction Phase Area a number of soil samples will be collected and submitted for radiochemical analysis and a Phase 2 Radiological contamination assessment completed. iv) Ground gas 13.3.52 A programme of ground gas monitoring has been undertaken within the Built Development Area West (Ground Gas Risk Assessment) A summary of the gas monitoring results is presented in Table 13.11.

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Table 13.11: Summary of Data from Six Gas Monitoring Visits for Borehole within the Built Development Area West

Piezometer Atmospheric Differential CH4 (% CO2 (% O2 (% CO H2S Flow VOCs Static Water Total Depth (m) ID Pressure Pressure vol.) vol.) vol.) (ppm) (ppm) (l/hr) (ppm) Level (m bgl) (mb) (Pa)

DBH04 991 to 1014 -2 to 2 <0.1 <0.1 to 3.0 2.0 to <1 to 3 <1 -8 to 0.9 <0.1 18.945 to dry 19.11 21.3

DBH09 994 to 1016 0 to 1 <0.1 <0.1 to 0.1 20.7 to <1 <1 -0.1 to <0.1 1.084 to 4.642 15.83 21.4 5.2

CBH11* 979 to 1015 0 <0.1 <0.1 to 0.1 21.0 to <1 <1 0 to 0.1 <0.1 6.44 to 6.882 38.38 21.2

CBH16 990 to 1016 0 <0.1 <0.1 to 0.1 20.5 to <1 to 2 <1 -0.1 to <0.1 8.39 to 11.552 48.18 21.1 0.3

CBH21 979 to 1015 -6 to 4 <0.1 <0.1 to 1.3 4.9 to <1 <1 -3.1 to <0.1 5.043 to 7.448 14.97 21.1 1.7

CBH24 980 to 1015 -9 to 13 <0.1 0.1 to 1.6 2.9 to <1 to 2 <1 -5.1 to <0.1 3.855 to 6.816 18.52 21.0 4.6

CBH25 979 to 1015 -1 to 1 <0.1 <0.1 to 0.6 18.5 to <1 <1 -1.5 to <0.1 0.825 to 3.723 16.95 20.7 1.2

CBH27 979 to 1015 -1 to 1 <0.1 <0.1 to 0.1 20.6 to <1 to 1 <1 -1.1 to <0.1 1.637 to 4.475 12.48 21.2 0.1

CBH29 995 to 1015 -2 to 3 <0.1 <0.1 to 0.1 20.7 to <1 to 1 <1 -0.2 to <0.1 15.637 to 54.15 21.4 1.4 16.495

CBH35 980 to 1015 0 to 12 <0.1 <0.1 to 0.7 18.9 to <1 <1 0 to 3.8 <0.1 6.592 to 7.587 11.57

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Piezometer Atmospheric Differential CH4 (% CO2 (% O2 (% CO H2S Flow VOCs Static Water Total Depth (m) ID Pressure Pressure vol.) vol.) vol.) (ppm) (ppm) (l/hr) (ppm) Level (m bgl) (mb) (Pa) 21.2

LOD - - 0.1 0.1 0.1 1 1 - 0.1 - - (equipment) (GA2000 (GA2000) (GA2000) (GA2000 (GA2000 (Mini- ) ) ) Rae)

LOD Limit of Detection.

Less< than LOD, variable per compound * CBH11 was not monitored during the first visit. DBH08 was only monitored during the first visit and thus the data are not presented within Table 1, although are included within Appendix E of the Ground Gas Risk AssessmentError! Bookmark not defined..

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land 13.3.53 The monitoring and sampling data indicate that concentrations of ground gases during the monitoring period varied across the Built Development Area West were generally very low. Trace levels of carbon monoxide were recorded at certain locations with a peak of 3 parts per million (ppm) being recorded in DBH04. 13.3.54 No hydrogen sulphide or volatile organic compounds (VOCs) were detected within any of the piezometers during any of the monitoring visits. 13.3.55 Recorded gas flow rates were very low, with readings generally slightly above and below a zero flow rate. A maximum positive flow of 5.2 l/hr was recorded in DBH09. 13.3.56 During the drilling works, as part of the first on-shore investigation of the Built Development Area West undertaken by Structural Soils Ltd in 2008 to determine the geotechnical and geological characteristics, elevated concentrations of hydrogen sulphide, nitrogen and carbon monoxide were detected in some boreholes during drilling. Hydrogen sulphide and odours were first detected in CBH19, followed by CBH01, CBH09, CBH10 CBH11 and DBH01. Elevated concentrations of carbon monoxide were also detected in CBH11 (concentrations ranged from 1 ppm to 12 ppm) and in CBH 19 (concentrations ranged from 0 ppm to 200 ppm). 13.3.57 Elevated nitrogen concentrations and associated depleted oxygen and high gas flow rates were recorded within DBH04 by Structural Soils Ltd (2009) (Ref. 13.12) immediately after the installation of this piezometer. Subsequent monitoring has indicated a reduction of the nitrogen concentrations (shown by an increase in oxygen concentrations and no high flows) throughout the monitoring visit. However, during the second on shore monitoring visit the elevated nitrogen concentrations (96 % volume) and high gas flow rates (>30 l/hr) were again observed in DBH04, and during drilling of eight additional locations concentrations of elevated nitrogen were detected. Subsequent monitoring indicates that the elevated concentrations have subsided. Continued monitoring of DBH04 and assessment of nitrogen levels is proposed as part of the further gas monitoring at the site. 13.3.58 The source of these gases is uncertain, but the hydrogen sulphide is thought to be associated with dissolved hydrogen sulphide in groundwater which is probably derived from the breakdown of natural organic matter in the underlying geology. 13.3.59 A programme of gas monitoring and subsequent ground gas risk assessment have not yet been undertaken on the Built Development Area East or Southern Construction Phase Area but are scheduled to be undertaken following the completion of the currently ongoing second on shore investigation.

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13.4 Assessment Of Risk Posed By Potential Contaminants

a) Introduction 13.4.1 This section provides an assessment of the risk posed by the disturbance and mobilisation of potential contaminants during the construction and operation of the Hinkley C nuclear power station. For this assessment, ‘contamination’ includes both radiological and non radiological contamination, unless otherwise specified. 13.4.2 The assessment is largely based on the results obtained through the site investigations work and the subsequent Tier I Risk Assessment undertaken with respect to the analysed samples. While it is recognised that there is still ongoing investigation work to be undertaken it is considered likely that the results and assessment, as presented here, are a reasonable reflection of the contaminant status of the Development Site and the likely level of risk posed. This is particularly so with respect to the Built Development Land West, where investigations have been completed. For the Built Development Land East further investigation results are awaited, but the majority of work has been undertaken, as reported here. Desk based assessment work has been largely utilised to provide an assessment of the status of conditions for the Southern Construction Phase Area, but given its historic usage, contamination is not expected to be an issue. 13.4.3 The assessment for the Built Development Land East presented here is for the land status prior to the implementation of Enabling Works during which much of the made ground occuring within this area is to be removed. In reality, the main site construction works, to which this ES applies, would therefore be undertaken under conditions in which most of the potential contaminant sources identified would have been removed. Although it is apparent that contaminant levels within the Built Development Land East are generally below identified risk levels, clearly the removal of much of the source of any potential contaminants prior to the construction works for the main site being initiated would lessen this risk even further. 13.4.4 A description of the stages, infrastructure and methods to be used in the construction of the proposed nuclear power station is contained within Volume 2 Chapters 2 and 3. b) Potential receptors and pathways 13.4.5 During the construction phase potentially contaminated soils may be mobilised, by construction activities e.g. soil disturbance and dust generation during earthworks. This mobilised soil may then have implications for a range of receptors, leading to potentially adverse impacts in some situations. 13.4.6 The following construction related activities may create and/or introduce new pathways and/or disturb and mobilise contamination:

 Excavation and filling operations (‘Cut and Fill’) particularly using granular and permeable soils and fills;  General earthworks/re-grading;  Piling;  Groundwater dewatering (see Chapter 14 on groundwater); and  Installation of drainage and services.

13.4.7 The following potential pathways/exposure mechanisms may exist during the construction phase:

 Direct contact, inhalation and/or ingestion with/of soils and/or gases and vapours;

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 Infiltration and leaching through areas of exposed Made Ground/soil and bedrock;  Windborne transport of soil and dust from areas of exposed soils and rock;  Migration of contamination via permeable soils and bedrock;  Migration via groundwater flow;  Migration via man made conduits (e.g. drainage, services, foundation piles, etc.);  Surface run off; and  Migration of gases and vapours into buildings and buried structures via cracks and defects in the floor slab, walls and via service entry points.

13.4.8 The following are considered to be potential receptors in relation to any contaminants contained in soild disturbed during the construction phase:

 Human health;  Controlled waters (i.e. site groundwaters and surface waters);  Buildings, services and other infrastructure; and  Plants, trees, crops and other vegetation.

13.4.9 The potential effects on the receptors listed above are covered in the relevant chapters of this volume (i.e. groundwater, hydrology and terrestrial ecology). Potential effects on human health are covered in the Health Impact Assessment (HIA). The potential for risk to human health from contaminated soil (known and potential) is summarised in the following sections. 13.4.10 The receptor group with the highest potential impact from soil contamination during the construction phase is construction workers. Off site users could potentially be exposed to contaminated soils via exposure pathways which include dust generation, odour/gas/vapour release and wind transport. 13.4.11 Currently there are no UK soil guidelines or threshold values for assessing the health risk to construction workers from soil contaminants. As a result the guidelines and methodologies used to assess whether soils and other materials are ‘hazardous’ under the Chemical (Hazard Information and Packaging Supply) Regulations 2009 (CHIP4), Hazardous Waste (England and Wales) Regulations 2005 and Approved Supply List Edition 8, have been used for this impact assessment. This is because many of the criteria for hazardous wastes are based on short term, i.e. acute hazard properties such as toxicity, corrosivity, flammability and irritability, etc, which are relevant to the short term exposures, characteristic of construction workers. c) Results of risk assessment 13.4.12 Using the Preliminary Conceptual Site Model (PCSM), potential risks posed to human health and other receptors by soil contamination which may be present on or off-site, have been determined and assessed. The following sections provide a description and summary of this work based on the Tier I risk assessment of the results obtained from the site investigations and an overall assessment of the likely risk posed by the construction and operational phases of the project on the identified receptors. i) Built Development Area West 13.4.13 As detailed in the baseline conditions, the Phase 1 desk study has shown that this area of the site has remained largely undeveloped with no significant historical contaminative uses identified. 13.4.14 For shallow soils (<0.3 m bgl) the Tier 1 risk assessment identified that contaminants were recorded at concentrations below the relevant human health SSVs. Thus, it is considered that the near surface soils on the Built Development Area West do not have the potential to cause an

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land unacceptable risk to human health with respect to the proposed construction and industrial end use. 13.4.15 The risk posed to other receptors, i.e. buildings, infrastructure and ecological systems, was also considered as part of the Tier 1 assessment. Arsenic concentrations were identified in excess of The Water Regulations Advisory Scheme (WRAS) Guidance Note 9-04-03 ‘The Selection of Materials for Water Supply Pipes to be laid in Contaminated Land’; however concentrations did not exceed the Wessex Water Soil Survey Guidance (WWSSG) threshold value (50 mg/kg) for this contaminant. Thus, it is considered that the near surface soils on the Built Development Area West pose a negligible risk to water supply pipes that may be laid in the ground to service the proposed development. It is also concluded that the risk to buried concrete is low based on levels of soil pH and soluble sulphate concentrations identified during the on-shore investigation. 13.4.16 In soils and ground >0.3 m bgl, the Tier 1 assessment identified that all contaminants were recorded at concentrations below the relevant human health SSVs. Thus, it is concluded that there is no potential source of soil contamination within either the made ground or deeper soils within the Built Development Area West, which has the potential to pose a significant risk to human health considering the proposed commercial and industrial end use. 13.4.17 Two samples contained concentrations of potentially phytotoxic contaminants in excess of the Tier 1 SSVs. These related to a sample of made ground (TRE21 0.0-0.3 m bgl) where a zinc concentration of 687 mg/kg was recorded and a slightly elevated water soluble boron concentration (5.1 mg/kg) in a natural ground sample (TRE01 at 0.97 m bgl). 13.4.18 Arsenic was detected at concentrations in excess of the WRAS guidance (10 mg/kg) but below the WWSSG value (50 mg/kg). A single marginally elevated concentration of selenium (3.1 mg/kg) and a number of pH levels, indicating slightly alkaline soil conditions (pH 8.1-8.5) were also identified in excess of the WRAS guidance in the natural deeper soils. It is concluded that the risk posed to water supply pipes by soils within the Built Development Area West is very low. 13.4.19 Contaminant concentrations from the additional samples obtained from the vicinity of Benhole barns and the infilled ponds were again recorded below the Tier 1 assessment criteria in all Made Ground samples. Slightly elevated zinc concentrations (328 - 446 mg/kg) compared to natural soil concentrations were identified in the vicinity of former Benhole Farm. Concentrations were not above any thresholds but along with the previous elevated concentration (687 mg/kg) identified in this area suggests the Made Ground does contain slightly elevated concentrations of zinc. 13.4.20 Within the natural ground samples obtained in the vicinity of Benhole the contaminants concentrations identified were all below the relevant human health and phytotoxic screening criteria. Two natural ground samples (TE81/ES2 and TE81/ES2D) did identify slightly elevated pH levels and high concentrations of cadmium above the WRAS thresholds. However, given they are isolated exceedences the risk posed to water supply pipes is considered to be very low. 13.4.21 Elevated concentrations of metals i.e. arsenic, cadmium, chromium, nickel, selenium and zinc, have been recorded when compared to conservative Tier 1 ecotoxicological SSVs. However, concentrations are considered to be generally consistent with local and UK background concentrations, with the exception of isolated zinc within the Made Ground and a hotspot of cadmium within the natural ground, and as such the risk posed to ecological systems from contaminants within soils on the Built Development Area West is considered to be negligible. 13.4.22 The radiochemical analysis results for the soil samples from the Built Development Area West land show that there is no evidence of significant contamination with anthropogenic

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land radionuclides and that the levels of radionuclides present are generally consistent with background levels. This conclusion is based on the following observations:

 The only anthropogenic radionuclide measurable by gamma spectrometry detected in any of the samples was caesium-137. Caesium-137 was detected in all of the surface samples at levels consistent with background due to atmospheric fallout and significantly below The Radioactive Substances (Substances of Low Activity) Exemption Order limit of 0.4 Bq g-1;  Carbon-14, which can be present both naturally and from man-made sources, was detected in one of the samples at levels consistent with adopted background values. The level detected was significantly below The Radioactive Substances (Substances of Low Activity) Exemption Order limit of 0.4 Bq g-1;  Tritium was detected in two of the samples at levels below The Radioactive Substances (Substances of Low Activity) Exemption Order limit of 0.4 Bq g-1; and  There were three instances of naturally occurring radionuclides (one for protactinium-234m and two for radium-226) exceeding screening values derived from the Radioactive Substances Act 1993. In all cases, the levels were below the Radioactive Substances Act 1993 Schedule 1 limits for the relevant radioelements.

13.4.23 Based on the radiological walkover survey, gamma dose rate measurements and the radiochemical analysis results for the soil samples, the risk to humans from radiological contamination on the Built Development Area West land is considered very low. In accordance with Part 2A regime definitions of contaminated land where radioactive contamination is concerned, the Built Development Area West land is not contaminated by radioactivity. Harm is not being caused nor is there a significant possibility of such harm being caused, where harm is defined as “lasting exposure to any person resulting from the after-effects of a radiological emergency, past practice or past work activity” 13.4.24 Gas monitoring during the main on shore investigations undertaken by Structural Soils Ltd in 2008 did report some slightly elevated concentrations of hydrogen sulphide and significantly elevated concentrations of carbon monoxide in some of the boreholes during drilling (Ref. 13.12). However, the reliability of this data is questionable. Post drilling monitoring has not detected any elevated concentrations of methane and/or carbon dioxide above 0.1 % v/v and 3.0 % v/v respectively. The characteristic situation for the BDAW has been assessed as CS1 (i.e. very low risk) and post drilling monitoring has not replicated these findings. Monitoring of gas during excavations (particularly deep excavations) and confined space entry could readily confirm whether such areas are impacted by elevated gas concentrations during the construction works. ii) Built Development Area East 13.4.25 The Phase 1 desk study of the Built Development Area East (Ref 13.7) indicated that this area has historically been used for potentially contaminative activities such as waste disposal/landfilling activities, a small sewage works, areas of construction and fabrication associated with the A station construction, contractors accommodation/areas (which included a number of small electrical substations, boiler houses and fuel storage tanks) during the construction of the existing Hinkley Point Power Station Complex. 13.4.26 Phase 1 and Phase 2 (Ref. 13.7 and Ref. 13.8) investigations have indicated that the likelihood of some types of soil contamination being present on the Built Development Area East is ‘certain’ given that the presence of Asbestos Containing Materials (ACMs) and of concentrations of some contaminants which may pose a low risk to buried concrete, ecology and plants and water supply pipes in this area has been confirmed. However, the risk posed by these

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land contaminants is assessed as low to moderate (in the case of ACMs which may be disturbed during construction works). 13.4.27 The known and potential physical extent of ACM and other contaminated soils on the Built Development Area East is considered to be only a ‘small’ to ‘partial’ area of the site, therefore, the magnitude of the potential source areas is assessed as ‘very low’ to ‘low’. 13.4.28 Upper Confidence Limit (UCL) concentrations for the samples taken from within the Built Development Area East are below the Tier 1 risk assessment criteria for risk to human health based on a commercial and industrial end use. The exception to this is pH, where concentrations were in marginal exceedance of the BS3882:2007 Topsoil Specification limit value (8.5 pH units) for topsoil (N.B. In lieu of any other UK guideline value for human health risk assessment for pH in soils , the pH value in BS3882:2007 has been used as this guidance for pH for screening purposes), in one made ground and one natural samples from Area 4. Moderately elevated pH levels have been identified at up to 10.6 pH units in Area 3 (construction and demolition materials), made ground in Area 2 (9.3 units) and made ground in Area 4 (11.4 pH units). 13.4.29 The elevated values within the made ground are attributed to the presence of mortar, plaster etc. within the construction and demolition materials. The risk to human health from this slightly elevated to elevated pH is currently very low and provided these fills are not re- used/replaced within the top metre in areas of planned landscaping, agricultural restoration or ecological habitat, the post development risk to human health is also considered to be very low. 13.4.30 Concentrations of contaminants in both made ground and natural ground within the Built Development Area East were largely below the respective phytotoxic risk thresholds. Within the made ground one sample from Area 5 was noted to exceed the Tier 1 thresholds for copper (241 mg/kg) and zinc (922 mg/kg) and one sample from Area 4 was noted to exceed the Tier 1 threshold for zinc (590 mg/kg). The Tier 1 threshold for boron in made ground was exceeded in one sample from Area 3 (3.5 mg/kg), one sample from Area 1 (3.6 mg/kg) and one sample in Area 6 (4.2 mg/kg). One sample of natural ground was also marginally above the Tier 1 phytotoxicity threshold for boron (4.2 mg/kg). 13.4.31 It is considered that the made ground in these locations may pose a low risk to vegetation. It is considered that the phytotoxic risk from these hotspots can be managed by ensuring these materials are not re-used/placed within the upper metre of the soil profile in areas of planned landscaping, agricultural restoration or ecological habitat. 13.4.32 With regard to the built environment, concentrations of total sulphate, have been frequently identified in made ground and on occasion in natural ground in exceedance of the relevant Tier 1 criteria, although the soil pH for both made ground and natural ground is slightly alkaline which reduces the potential for sulphate chemical attack on subsurface concrete. It is considered that further assessment of the need for and appropriate specification of, sulphate resistant concrete will be addressed by other studies. 13.4.33 Within the made ground pH, selenium, sulphate and total petroleum hydrocarbons (TPH) and an isolated polycyclic aromatic hydrocarbon (PAH) concentrations were recorded slightly above the Water Regulations Advisory Scheme (WRAS) risk assessment values. As such, the made ground may not be considered suitable where standard water supply pipes are proposed to be laid unless mitigation measures are put in place. 13.4.34 Concentrations of arsenic, cadmium, chromium, copper, zinc, nickel, selenium and lead have been identified in exceedance of the conservative Tier 1 ecotoxicological SSvs. For the majority of the Built Development Area East concentrations of these contaminants in both made ground and natural ground were generally similar (with the exception of isolated higher concentrations

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land of copper, nickel, lead and zinc within the made ground). Indeed in several cases sample concentrations for natural ground exceeded the made ground concentrations. This indicates that although exceedances of Tier 1 assessment criteria have been identified, the concentrations recorded are reflective of natural background soil concentrations identified on the Built Development Area West rather than being indicative of an anthropogenic source of contamination. As a result the concentrations recorded are not considered to pose an ecotoxicological risk should the soils be re-used on site for restoration purposes. 13.4.35 Elevated concentrations of hydrocarbon contaminants in exceedance of Tier 1 ecotoxicological risk assessment criteria have been identified on the Built Development Area East at isolated locations. Elevated concentrations of PAHs above Tier 1 screening concentrations have been found in a limited number of areas of natural soil samples (benzo(a)pyrene and total PAHs) (Area 2), (anthracene, benzo(a)pyrene and total PAHs) (Area 4) and Made Ground soil samples in Areas 2, 3 and 4 (anthracene benzo(a)anthracene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene and total PAHs). 13.4.36 With the exception of ACMs, the only visual or olfactory evidence of contamination identified were observations of hydrocarbon staining in TE42 and the identification of elevated VOCs during in-situ screening of arisings with the photoionisation detector (average 6.4-10.3 ppm, peaks 23.7 and 31.9 ppm at 0.3 – 0.5 m) from TE54. 13.4.37 ACMs have been identified in a small number of locations across the Built Development Area East. The occurrence of these materials has been confirmed to be both as competent, cemented materials (asbestos cement) and as fibrous lagging and insulation materials, associated with presence of construction and demolition waste materials. However, analysis of soils associated with suspected and confirmed asbestos containing materials have not detected any diffuse fibres in the soil matrix. As such the risk from these ACMs and free fibres release from the soils in their current state is considered to be low. 13.4.38 The risk of mobilising any potential ACMs and freeing fibres may be increased during proposed earthworks and construction. Exposure to free fibres can result in permanent health effects. However, limited quantities of asbestos contamination have been identified to date and the risk would appear to be localised to specific areas of the site. As such there is a potential moderate risk to human health. 13.4.39 The majority of site soils within the Built Development Area East have been found to have low contaminant concentrations and are considered to be generally comparable with background concentrations found within the Built Development Area West. The majority of the site soils within the Built Development Area East are therefore considered to be suitable for the proposed end use given the incorporation of standard design mitigation measures where necessary (such as sulphate resistant concrete and contaminant resistant water supply pipes) and appropriate materials management and placement (e.g. not within top metre in some cases) during the earthworks. 13.4.40 The results of Waste Acceptance Criteria (WAC) testing indicate that exceedances of the leachable criteria for inert waste have been recorded for molybdenum (3 samples of made ground within Area 3 containing demolition/construction wastes and two samples of made ground from Area 4) and sulphate (3 samples from made ground comprising natural reworked soils in Area 3). Consultation with the Environment Agency and the receiver of the wastes will be required, in the event that off-site re-use or disposal of soil material is required, to determine whether the materials can be accepted as inert waste or alternatively whether a non-hazardous classification will be applied with respect to chemical contamination. 13.4.41 In addition to the standard WAC testing above, an assessment of the type and concentration of non radiological contaminants in the soils of the BDAE was undertaken to see if they may

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land contain any Dangerous Substances and/or possess any of the Hazard Properties (H1 to H14). The conclusion of this assessment is that on the basis of the soil contaminant concentrations available to date and with the exception of asbestos and ACMs, the soils on the Built Development Area East would not be classified as hazardous wastes. 13.4.42 The radiochemical analysis results for the soil samples reported to date from the Built Development Area East land show that there is no evidence of significant contamination with anthropogenic radionuclides and that the levels of radionuclides present are generally consistent with background levels:

 The only anthropogenic radionuclides detected were caesium-137 and americium-241. The levels of caesium-137 detected were consistent with background due to atmospheric fallout. Americium-241 was detected in one sample at a level close to the limit of detection;  The levels of anthropogenic radionuclides detected were significantly below The Radioactive Substances (Substances of Low Activity) Exemption Order limit of 0.4 Bq g-1;  Carbon-14, which can be present both naturally and from man-made sources, was detected in a number of the samples at levels consistent with adopted background values. The levels detected were significantly below The Radioactive Substances (Substances of Low Activity) Exemption Order limit of 0.4 Bq g-1;  Tritium was not detected in any of the samples;  Gross alpha and gross beta results were consistent with values reported for the Built Development Area West Land; and  None of the naturally occurring radionuclides present exceeds screening values derived from the Radioactive Substances Act 1993.

13.4.43 During the Phase 2 intrusive survey works, two areas were identified that provided elevated readings during routine health physics monitoring. In both cases, samples were collected and subjected to a gamma spectrometry screen. The gamma spectrometry screening data indicate that the elevation is due to naturally occurring radionuclides, principally from the uranium-238 natural decay series. The levels of the naturally occurring radionuclides present are estimated to be significantly below the limit of 14.8 Bq g-1 specified in the Radioactive Substances (Phosphatic Substances, Rare Earths etc.) Exemption Order 1962; hence are exempt from control under the Radioactive Substances Act 1993. However, the estimates are based on a relatively crude measurement protocol and further samples from these locations will be analysed using the full radiochemical testing suite used for the other soil samples. 13.4.44 Based on the radiological walkover survey, gamma dose rate measurements and the radiochemical analysis results to date for the soil samples, the risk to humans from radiological contamination on the Built Development Area East land is considered very low. In accordance with Part 2A regime definitions of contaminated land where radioactive contamination is concerned, the Built Development Area East land is not contaminated by radioactivity. Harm is not being caused nor is there a significant possibility of such harm being caused, where harm is defined as “lasting exposure to any person resulting from the after-effects of a radiological emergency, past practice or past work activity”. iii) Southern Construction Phase Area 13.4.45 A Phase 1 desk study of the Southern Construction Phase Area has concluded that the area is currently greenfield agricultural land and has historically been undeveloped, agricultural land. On the basis of the desk study, and the fact that the Southern Construction Phase Area has a very similar historical and current land use to that of the Built Development Area West, the likelihood of significant soil contamination in these areas is currently assessed as ‘unlikely’ and the magnitude of soil contamination is considered to be ‘very low.’

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land iv) Off site sources of contamination 13.4.46 The Phase 1a desk study and review of available reports relating to the off site HPA and HPB stations, has confirmed that there are several areas of potential and confirmed contamination of soils principally by hydrocarbons. Given that the topographical, geological and hydrogeological gradients generally fall towards the north/north east, the likelihood of any of this off site contamination migrating onto the development area under normal conditions is considered to be low. A groundwater risk assessment including risk of contaminant mobilisation from dewatering is detailed in Chapter 14. 13.4.47 The majority of the remaining land surrounding the study area is currently (and has historically only ever been) agricultural/greenfield land. In view of this, the likelihood of significant off site sources within these areas is considered to be ‘unlikely’. In addition, the physical extent of any such off site sources on these lands is assessed as small/localised, therefore the potential magnitude is ‘very low’ (i.e. as per the Built Development Area West and Southern Construction Phase Area). d) Approach to control and management of potential risk during construction 13.4.48 On the basis of the studies and investigations undertaken to date it is apparent that the potential risk of harm to humans and other receptors as a result of exposure to contaminants during the construction phase is negligible to low. As such there is considered to be no basis for any specific management or control measures to be put in place to ensure that contaminant sources are managed or controlled during the construction phase. This conclusion is, however, based on the following:

 That the Enabling Works are undertaken and the identified ACMs and sources of other contaminants are removed prior to the construction works commencing; and  That the ongoing and planned site investigations for the Built Development Area West and Southern Construction Phase Area do not reveal the existence of any sources of potential contaminants that would significantly increase the assessed level of risk. In line with current knowledge this situation is considered unlikely.

13.4.49 It is considered good practice to prevent and/or minmise potential impacts and risks as far as reasonably possible. In respect of this, standard good practice measures and management will be utilised during the construction phase to ensure that the potential for risk of exposure to contaminants and their mobilisation through the pathways identified previously is appropriately controlled. 13.4.50 Such measures will be contained in the Environmental Management and Monitoring Plan (EMMP) and the Site Waste Management Plan. Standard measures would also be employed during construction to prevent and minimise the release of potentially contaminated materials into the environment from their original source location. Certain standard control measures which are typically applied on construction sites where substantive earthworks are undertaken, are also effective at controlling the dispersion and creation of contamination. 13.4.51 Potential measures for controlling risk from contaminated soils include:

 Removal and/or remediation ;  Careful materials management planning (e.g. selective re-use/replacement of soils at appropriate places and depths);  Appropriate design and specific built infrastructure (e.g. The Construction Design and Management and the Nuclear Site Licences will require that the buildings and associated infrastructure on the site are appropriately designed and constructed to protect against any potential impact via contaminated soils or ground gas); and

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 Standard good construction practices/environmental protection e.g. dust control.

13.4.52 Following completion of the planned additional intrusive investigations, any areas of unsuitable materials (e.g. asbestos containing materials, wood, paper, plasticm metals, old drums etc) and/or soils contaminated above unacceptable thresholds would be removed and/or remediated prior to/or during the preliminary earthworks. 13.4.53 A ‘watching brief’ would then be maintained during the remaining main construction earthworks, so that in the event that additional areas of unsuitable materials or suspected contaminated soils are encountered, these areas would be isolated, removed, segregated (e.g. in a specific ‘quarantine’ area) and tested to decide whether they are suitable for re-use on site, require further remediation, or would be disposed off site. 13.4.54 Measures to deal with the potential mobilisation of contaminants as a result of modification of the groundwater regime during construction are provided in Chapter 14. e) Potential impacts during the operational phase 13.4.55 The following are considered to be potential contaminant migration and/or exposure pathways during the operational phase:

 Direct contact, inhalation and/or ingestion by humans of soils and/or gases and vapours;  Migration of contamination via permeable soils and bedrock;  Migration via groundwater flow  Migration via man made conduits (e.g. drainage, services, foundation piles etc.);  Surface run off; and  Migration of gases and vapours into buildings and buried structures via cracks and defects in the floor slab, walls and via service entry points.

13.4.56 The potential sources of contaminants during operation (other than those that could potentially be released accidentally) would be restricted to those soils which may be retained and re- deposited within the fills used on site during the construction works. 13.4.57 The likelihood, however, of significant levels of contaminants being contained within these fill materials is considered to be very unlikely. Given the low levels of contaminants recorded during the site investigations and that earthmoving activities during construction would effectively further attenuate any contaminants present in soils the level of potential risk of contaminant exposure is considered extremely low. 13.4.58 As any of the fill materials from construction would effectively be imobillised during operation and would be unlikely to be re-dsiturbed, the only potential risk to human health from soil contamination during the operational phase is to on site maintenance and construction workers who may be required to undertake works in the subsurface environment (e.g. for repairs to underground infrastructure). These worker groups may come into close contact with soil (particularly during excavations). 13.4.59 Off site users and ecological interests could potentially be exposed to contaminated soils via pathways such as surface water run-off, groundwater migration and discharge of effluents to the marine environment. Analysis of the pathways by which these contaminants could be mobilised is considered in the Environmental Appraisal chapters on hydrology and groundwater, while the potential effects are considered in the HIA and the ES chapters on terrestrial ecology and marine ecology. i) Operational phase mitigation measures 13.4.60 The only potential significant issue identified during the operational phase is the impact to on site workforce involved in site maintenance and construction activities from contaminated soils.

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ENVIRONMENTAL APPRAISAL – VOLUME 2 13 Contaminated Land With regard to this subject, this issue is identified as of low risk and its significance is not assessed here but in the Health Impact Assessment where further relevant information relating to operational effects on human health is provided.

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References

13.1 Ordnance Survey 2005 Explorer Map 1:25,000 scale ‘Quantock Hills & Bridgwater’ Sheet 140 13.2 British Geological Survey (BGS) 1:50000 BGS Sheet 279; Weston-Super-Mare 13.3 Whittaker, A, and Green, G.W 1983. Geology of the country around Weston- Super-Mare: Memoir for 1:50000 geological sheet 279, New Series, with parts of sheets 263 and 295. Institute of Geological Sciences, London 13.4 Rendel Palmer and Tritton 1986. Hinkley Point ‘C’ Power Station Pre-Application Studies, Volume 2 Geotechnical Report 13.5 Allot Atkins Mouchel 1988. Hinkley point ‘C’ Power Station Geotechnical Studies, Geotechnical Summary Report – Chapter 7. Report Ref: HPC 1101/57. 13.6 Aspinwall & Company 1996. Analysis of Groundwater Conditions at Hinkley Power Station. Report Ref: NU5101B for Nuclear Electric. 13.7 Phase 1 Desk Study and Preliminary Assessment 13.8 Phase 2 Supplementary Investigation 13.9 CIRIA 665 ‘Assessing risks posed by hazardous ground gases to buildings’ (2007) 13.10 Serco 2006. Baseline Survey of an Area of Land to be leased from British Energy at Hinkley Point. Report Ref: SA/Env/ 0878/ Issue 1 for British Nuclear Group Magnox Electric Ltd. 13.11 Environment Agency, Guidance on the Characterisation of Radioactively Contaminated Land (2002) 13.12 Structural Soils Ltd February 2009. Factual Report on Ground Investigation: On Shore Investigations for Hinkley Site, Report Ref: 721763.

Literature Consulted

English Nature ‘Geological site documentation/management brief, Blue Anchor to Lilstock Coast’, 1993). Serco (December 2008). Pre-Closure Contamination Survey (C Station Land), Hinkley Point A. Report Ref: TAS/002838/001 Issue 01 for Magnox South

British Standards Institute. (2007). BS3882:2007 Specification for topsoil and requirements for use Radioactivity in Food and the Environment, 2007, RIFE 13 (2008) Radioactivity in Food and the Environment, 2008, RIFE 14 (2009) Her Majesty’s Inspectorate of Pollution. (1993) Natural Radionuclides in Environmental Media. DOE Report No. Doe/HMIP/RR/93/063 United Nations Scientific Committee on the Effects of Radiation (2000), UNSCEAR Report, Annex B – Exposures from Natural Radiation Sources The Radioactive Substances (Substances of Low Activity) Exemption Order, Statutory Instrument 1986, No. 1002 and amended 1992, No. 647 Department of the Environment, Food and Rural Affairs, Defra Circular 01/2006, Environmental Protection Act 1990: Part 2A, Contaminated Land (2006) Ionising Radiation Regulations 1999, HMSO Radioactive Substances (Phosphatic Substances, Rare Earths etc.) Exemption Order 1962

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