1 ENVIRONMENTAL APPRAISAL: SUMMARY

1.1 Introduction

1.1.1 This document is a non-technical summary of the Environmental Appraisal which has been prepared to accompany a consultation by EDF Energy on the development of a new nuclear power station, with On-site and Off-Site Associated Development, at Hinkley Point in . 1.1.2 This consultation forms part of the pre-application process for seeking Development Consent. EDF Energy is asking for views from people living in the vicinity, the general public and other interested parties on the proposed Hinkley Point C Project, and will take these into account when it makes its formal application. 1.1.3 The Environmental Appraisal is not an Environmental Statement. It is designed to enable consultees to give an informed response to the environmental effects of the project from information compiled by EDF Energy up to this stage of the project’s development.

1.2 The Site

1.2.1 Hinkley Point C is located on the West Somerset coast, 25km to the east of Minehead and 12km to the north-west of . See Figure 1.1. The Hinkley Point C Development Site occupies an area of approximately 176 hectares (ha) of which approximately 66.6ha will be permanent development, Figure 1.2. 1.2.2 The Hinkley Point C Development Site lies immediately to the west of the existing nuclear power stations at Hinkley Point A and Hinkley Point B. The surrounding area is mainly agricultural with scattered settlements, typical of the Vale of Taunton and Quantock Fringes. 1.2.3 The main access road serving Hinkley Point is the C182. This runs from Hinkley Point through the village of Cannington to join the A39 to Bridgwater and Minehead to the south of the village. At Bridgwater the A38 links to the M5 motorway north and south at Junctions 23 and 24 respectively. 1.2.4 The Hinkley Point C Development Site is bounded to the north by the , part of the Severn Estuary from which it is separated by a low cliff. The Severn Estuary is recognised for its international and national nature conservation importance.

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ENVIRONMENTAL APPRAISAL: SUMMARY Figure 1.1

1.3 The Development

1.3.1 The proposed Hinkley Point C nuclear power station will comprise two Pressurised Water Reactors (known as UK EPRs) together with shared facilities. Figure 1.3 provides an illustrative view of the main features of a single EPR reactor unit. Figure 1.3

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 3 ENVIRONMENTAL APPRAISAL: SUMMARY 1.3.2 At the heart of the UK EPR is a 10m high, 5.5m diameter steel pressure vessel containing the reactor core which is loaded with uranium dioxide fuel and cooled by water. Heat is produced by nuclear fission of the uranium and is transferred to steam generators by the cooling water which is maintained under pressure to prevent it from boiling. The reactor pressure vessel, steam generators and associated pipe work and plant are all contained within a reinforced concrete structure designed to withstand the crash of a commercial airliner. 1.3.3 The steam generators take the hot water from the reactor and use it to turn water in a separate secondary circuit into steam. This steam is used to power a single large turbine which is connected to a generator capable of producing around 1630 Megawatts (MW) of electrical power. This is enough electricity to power approximately 2.5 million homes. Seawater circulating in a third separate circuit is then used to condense the steam back into water before it is returned to the steam generators. 1.3.4 The reactor is shut down every 1 – 2 years for refuelling, inspection and maintenance. Spent fuel removed during refuelling is highly radioactive and is stored underwater in a fuel pond which provides cooling and shielding. After an initial period of cooling of around 10 years, the spent fuel is transferred to an on-site store which will be capable of safely managing the fuel until the UK National disposal facility is available. 1.3.5 The proposed layout of the Hinkley Point C Development Site is shown in Figure 1.4. This layout reflects the key drivers of safety, security and engineering, whilst taking into account the surrounding landscape and the presence of the existing power stations. 1.3.6 In order to export power from Hinkley Point C to the national grid high voltage electricity transmission system a new 400 Kilovolt (kV) substation will need to be built on the site. The substation will be connected to the turbine hall by two EDF Energy overhead line circuits within the site boundary. To facilitate connections between the proposed substation and the national grid high voltage electricity transmission system, six overhead line landing gantries along the southern and eastern boundaries of the substation site will connect via overhead line to three overhead line terminal towers. These will be included in EDF Energy’s Development Consent application. 1.3.7 Modifications to the existing overhead line network beyond the terminal towers to the south east of the substation will also be required and will form part of a separate Development Consent application by National Grid.

1.4 Construction Activities

1.4.1 The site preparation and construction works will take approximately nine years. The main phases will comprise:

 site preparation works including site clearance, establishment of contractor compounds, major earthworks to terrace the site and create platforms, construction of a new sea wall, installation of a new drainage system;  construction of a temporary jetty to allow transport of bulk materials to the site by sea;  tunnelling for the cooling water pipes;  construction of substructure and foundations; and  construction of buildings, installation of mechanical and electrical services and fit out of each building 1.4.2 During the construction programme, the workforce for Hinkley Point C is expected to peak at approximately 5000 after about six years. During the first phase of construction single shift

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ENVIRONMENTAL APPRAISAL: SUMMARY working will be adopted, moving to double shift by the construction peak. Later on, three shift working may need to be adopted. 1.4.3 The main construction period of Hinkley Point C will require the delivery of approximately 5.1 million tonnes of material of which around 75% will be in the form of bulk materials (i.e. fill, aggregates, sand and cement) and steel reinforcement bars. 1.4.4 It is proposed that bulk aggregates will be imported to the Development Site by sea wherever practicable. It is expected that transport by sea via the jetty will account for approximately 80% or more of this material. 1.4.5 The construction period will also require the delivery of Abnormal Indivisible Loads (AILs). These are large items of plant that are manufactured off-site and which are too large to be transported by road. To accommodate these, Combwich Wharf will be refurbished and supported by a freight logistics facility.

1.5 Off – Site Associated Development

1.5.1 The construction of Hinkley Point C will require development away from the main site to facilitate the build process. These Off-Site Associated Developments are concerned primarily with improving the local transport infrastructure for both freight and workforce movements and providing accommodation. The following main facilities are proposed:

 Cannington Bypass;  refurbishment of Combwich Wharf;  accommodation campuses;  freight logistics and storage facilities; and  park and ride facilities.

1.6 Potential Environmental Impacts and Mitigations: Main Site

a) Radioactive Discharges 1.6.1 An operating nuclear power station will make very small discharges of radioactive material to the environment. These releases are subject to authorisation by the Environment Agency in England and Wales, and a strict requirement to use Best Available Techniques (BAT) to minimise the discharges such that they are “As Low As Reasonably Practicable” (ALARP). 1.6.2 Everyone in the UK (and worldwide) is exposed to radiation from both natural and man-made sources. The Health Protection Agency (HPA) has estimated the annual exposure (or dose) to the UK population from all sources of radioactivity and their findings are summarised in Table 1.6.1. Radioactive doses to people are measured in sieverts, normally expressed as millisieverts or microsieverts (one thousandth or one millionth of a sievert respectively).

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 5 ENVIRONMENTAL APPRAISAL: SUMMARY Table 1.6.1: Average annual doses to the UK population from all sources of radiation

Source Dose (millisieverts mSV)

All natural sources (average) 2.2

Made up on average from:

natural gamma radiation 0.35

natural cosmic radiation 0.33

naturally radioactive materials internal to our bodies 0.25

naturally occurring radioactive radon gas (a) 1.3

Medical exposure to radiation (X-rays etc.) 0.41

Occupational exposure 0.006

Fallout from earlier nuclear weapons testing 0.006

Products containing radioactivity 0.0001

Discharges from nuclear industry 0.0009

Total (b) 2.7

Key (a) The dose attributed to naturally occurring radon gas varies with location, house construction materials, ventilation rates and other factors. A typical range of 1-6 mSv per year is presented by the HPA (see reference above).

(b) Based on variability in the typical dose from naturally occurring radon (see above) a typical total dose to the UK population may vary from 2.3 to 7.3 mSv per year.

1.6.3 Natural sources are much more important than man-made radioactivity, amounting to 81% of the average annual dose. By contrast the dose from radioactive discharges (which includes releases from power stations) is extremely small, amounting to around 0.0004% of the average annual dose. 1.6.4 The EPR is designed and will be operated to reduce radioactive discharges to a practicable minimum. Discharges are minimised by:

 minimisation at source, for example by ensuring the integrity of fuel pins to minimise any release of fission products;  recycling and re-use of liquids where possible in the reactor systems;  removing radioactivity from liquid discharges using combinations of filters, ion exchange resins and evaporators; and  treatment of gaseous discharges to capture tritium for discharge as a liquid (tritium has a much smaller environmental impact when discharged to seawater) and the provision of

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ENVIRONMENTAL APPRAISAL: SUMMARY hold-up and delay facilities for the short-lived isotopes of krypton and xenon, sufficient to ensure that only very low levels of these are finally discharged into the atmosphere. 1.6.5 The HPA has proposed to the UK Government that there should be a radioactive dose limit to members of the public from a new nuclear power station of 0.15 mSv per year. 1.6.6 Radioactive discharges are assessed by modelling their possible impact on a hypothetical group of people whose habits would result in them being the most exposed. This group of people is often known as the “critical group”. 1.6.7 Two critical groups were modelled for Hinkley Point C: a hypothetical farming family who lived close to the site and ate locally caught seafood and a hypothetical fishing family who caught fish in the area and also ate seafood. In both cases, the highest predicted dose at around 0.004 mSv was a small fraction significantly less than the HPA’s proposed 0.15mSv, amounting to around 3% of the proposed dose limit. This is also similar to the dose that would be received from cosmic radiation during a return flight within the UK or from a dental X-ray. 1.6.8 The potential radiological effect on wildlife habitats was considered by modelling the impact of discharges on habitats in the vicinity of the power station. In all cases the dose was calculated to be negligible and well below the Environment Agency’s wildlife dose limits. 1.6.9 The modelling and assessment of the proposed discharges of radioactivity from Hinkley Point C all show that, when judged against the stringent internationally agreed criteria for radiological protection, the impacts on people and wildlife are negligible and any dose impact is dwarfed by the contribution from natural radioactivity. b) Radioactive Waste Management 1.6.10 Three categories of solid radioactive waste will be produced during the operations of Hinkley Point C. It is not expected that any radioactive waste will be produced during construction. The categories are:

 Low Level Waste (LLW): material from routine operations which is lightly contaminated with radioactivity.  Intermediate Level Waste (ILW): material with higher concentrations of radioactivity, normally requiring shielding during handling to protect the operators.  Spent Fuel: not strictly waste as it contains potentially re-usable uranium and plutonium. However in the absence of reprocessing, it will need to be disposed of. Spent fuel is highly radioactive and continues to generate heat and therefore requires both shielding and cooling. 1.6.11 Management of wastes at Hinkley Point C will be subject to an Integrated Waste Strategy (IWS) to ensure a consistent and safe approach is taken when making decisions on waste management. The IWS covers all wastes, both conventional and radioactive, and aims to ensure that workers, the public and the environment are protected during the construction, operation and decommissioning of the station. 1.6.12 LLW will be disposed of from Hinkley Point C as soon as is reasonably practicable, following treatment to minimise volume and provide appropriate conditioning and packaging. Disposal will be by one of the following routes, depending on the physical and chemical nature of the waste:

 treatment of metals for potential recycling;  incineration of combustible wastes in an off-site commercial incinerator;  use of an authorised disposal facility for exempt and very low level wastes (notably for soil, rubble and aggregates);

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 7 ENVIRONMENTAL APPRAISAL: SUMMARY  transfer of compactable wastes to an off-site super compactor before disposal at the Low Level Waste Repository (LLWR) to reduce volume; and  disposal directly to the LLWR will only be used where there is no practicable alternative. 1.6.13 There is no current disposal route for ILW pending the development of the UK Geological Disposal Facility (GDF). At Hinkley Point C, ILW will be conditioned and packaged prior to interim on-site storage in a purpose built store capable of safely and securely holding the entire lifetime arisings of ILW from the two reactors. ILW will be transported off-site for disposal once the GDF is available to accept wastes. 1.6.14 There is no current disposal route for spent fuel which is also expected to be disposed of to the GDF. Spent fuel removed during refuelling is highly radioactive and is stored underwater in a fuel pond which provides cooling and shielding. After an initial period of cooling of around 10 years, the spent fuel is transferred to an on-site store, which will be capable of safely managing the fuel until the GDF is available. 1.6.15 The radiological implications of waste management are considered in the previous section on radioactive discharges. Other radioactive waste related environmental impacts, such as construction and decommissioning of the facility and off-site transport of LLW are considered to have negligible adverse consequences. c) Non-Radioactive Waste Management 1.6.16 There are three main types of non-radioactive waste:

 Inert waste: defined as waste which does not react or undergo any physical, chemical or biological changes. This includes building rubble, waste glass and concrete.  Non-Hazardous waste: defined as waste which is not hazardous waste. This includes uncontaminated wood, metals, plastics and paper.  Hazardous waste: defined as certain types of waste that is specifically identified in the Hazardous Waste Regulations 2005. This includes oils, chemicals, batteries and materials contaminated with hazardous substances. 1.6.17 All wastes (including radioactive wastes) generated on the Hinkley Point site will be managed through an Integrated Waste Strategy (IWS), to ensure that a consistent and safe approach is taken for all waste management decisions and to ensure compliance with environmental protection principles is maintained. 1.6.18 The IWS includes:

 minimisation of waste via application of the waste hierarchy;  application of Best Available Techniques;  review and application of operational experience;  compliance with regulatory obligations and Government policy; and  consideration of a full range of health, safety, environmental, security, economic and social issues. 1.6.19 The management of specific waste streams during construction and operation is set out in the non-radioactive waste management chapter of the Environmental Appraisal. d) Decommissioning 1.6.20 The decommissioning strategy to be adopted at Hinkley Point C will be early site clearance. This means that decommissioning starts as soon as possible after the end of generation and carries on until the site is cleared and delicensed. With the exception of the spent fuel interim storage facility, which will be retained on site until a GDF is able to accept the spent fuel for disposal,

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ENVIRONMENTAL APPRAISAL: SUMMARY decommissioning of the site is expected to take around 20 years from the end of electricity generation. 1.6.21 The costs of decommissioning (and spent fuel management and disposal) will be met from contributions made by EDF Energy into a segregated fund over the operating life of the power station. These arrangements will be formally set out in a Funded Decommissioning Programme. This will be approved by the Secretary of State and be legally binding on EDF, thereby ensuring that decommissioning, waste management and disposal costs are covered in full. 1.6.22 All decommissioning activities, with the exception of waste transport, will take place within the site licence boundaries of the Hinkley Point C site. The end point is currently assumed to be delicensing of the site followed by landscaping and return to grassland. 1.6.23 Before decommissioning can begin, consent is required from the Health and Safety Executive (HSE). This will involve the production of a full environmental impact assessment and pubic consultation which will be carried out immediately before the end of generation (around 60 years after the start of operations). However, based on our current information EDF Energy considers that the environmental impact of decommissioning, once suitable mitigations are in place, will be minor to negligible. e) Impacts on People 1.6.24 The construction and operation of Hinkley Point C has the potential to impact on people in a number of ways including:

 noise and vibration;  traffic;  air quality; and  socio – economics. 1.6.25 EDF Energy has commissioned studies to investigate the potential impacts and, where appropriate, propose mitigations. The detail of this work is set out in the individual Environmental Appraisal chapters. A brief summary of the most significant environmental effects and their proposed mitigations is set out here. f) Noise and Vibration 1.6.26 The potential effects of noise and vibration may be associated with:

 on-site construction operations including the movement and operation of a wide range of mobile or stationary construction plant equipment, and specifically with regard to ground compaction or piling activities;  off-site construction-traffic effects that may influence noise and vibration sensitive premises;  on-site operational noise; and  off-site operational transport-related movements. 1.6.27 In a worst case assessment, with all plant working at the closest approach, the overall impact on the nearest properties (Doggets and Bishops Farm House) is assessed as major. These impacts will however be of short duration being attributed to ground preparation works. 1.6.28 Mitigation activities are proposed to include:

 the construction of an earth bund above Doggets which will be established as part of the ground preparation for the accommodation campus;  noisy night time working on the Hinkley Point C Development Site to be kept to a minimum and the normal working day to be used wherever possible; and

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 9 ENVIRONMENTAL APPRAISAL: SUMMARY  if blasting operations are required, measurement of vibration will be required at the nearest receptor location to ensure compliance with the exposure criteria. 1.6.29 Following mitigation, all impacts are considered to be minor to negligible. g) Traffic and Transport 1.6.30 The construction of Hinkley Point C will require the importation of very large quantities of building and engineering materials and a major increase in the workforce over a period of around nine years. This will generate a significant increase in traffic movements and EDF Energy is proposing an extensive range of mitigation measures to reduce any impact to a practicable minimum. These measures include:

 Construction of a temporary jetty at Hinkley Point C to receive bulk loads of construction materials. This is expected to account for about 80% by volume of aggregates, substantially reducing road based deliveries.  Upgrading of Combwich Wharf to receive very heavy or large plant items via the , together with the development of a freight logistics facility. Freight would be transported to the Hinkley Point C Development Site via the private access road from the wharf and the C182 road thus avoiding major population centres.  A freight logistics facility is to be built near Junction 23 of the M5 motorway. This would intercept and, where possible, consolidate deliveries of material onto a reduced number of vehicles on the local road network. A further facility would also be built at Junction 24 of the M5 to enable the flow of freight vehicles to be controlled, (but this would not include freight consolidation facilities?)  Four park and ride facilities to manage the transportation of workers to and from the Hinkley Point C Development Site. These would be located near to Junctions 23 and 24 of the M5 motorway, to the west of Williton and to the south-west of Cannington.  A package of highway mitigation measures within the urban areas of Cannington and Bridgwater to include junction improvements, traffic management, speed reduction measures and safety enhancements. 1.6.31 Bypasses of Cannington and Bridgwater have been considered, and detailed technical traffic studies carried out. EDF Energy’s strategy has been to minimise the generation of traffic through the mitigation measures mentioned above and results of the transport studies indicate that there is no technical requirement for a bypass at Cannington or Bridgwater. 1.6.32 EDF Energy believes, however, that particular considerations arise at Cannington. Whilst the level of traffic anticipated could be accommodated within the capacity of the roads in Cannington – and whilst assessments suggest that no noise or air quality standards would be breached – the change in traffic levels from existing flows and the nature of that traffic would be more pronounced in Cannington than elsewhere. EDF Energy believes therefore, that it would be beneficial to include a Cannington western bypass as part of its proposals and for the bypass to remain as a permanent legacy of the HPC development, diverting extraneous construction, maintenance and operational traffic away from the centre of the village. 1.6.33 Further mitigation of transport impacts will be achieved through the development of a Framework Travel Plan. This will describe the car parking provision and proposed travel arrangements and controls for workers to minimise peak traffic impacts and the use of single occupancy vehicles. 1.6.34 With the adoption of the mitigation measures, all residual impacts are considered to be minor to negligible.

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ENVIRONMENTAL APPRAISAL: SUMMARY h) Air Quality 1.6.35 The potential sources of air pollution associated with the development include:

 on–site construction activities including plant exhaust emissions and the generation and dispersion of construction dust;  vehicle exhaust emissions from off-site construction traffic movements;  emissions associated with construction period and marine transportation;  on-site power station operational emissions from routine, test and emergency scenarios; and  emissions from off-site operational transport related movements. 1.6.36 The impact of dust and emissions from construction activities on the nearest properties to the site has been assessed as minor to negligible, with the exception of Doggets, which is the most affected property and where the impact is considered to be moderate to adverse. 1.6.37 To mitigate the construction impact, an Environmental Management and Monitoring Plan (EMMP) will be drawn up to ensure good control and management techniques are adopted to protect potentially affected properties. The measures are likely to include:

 sheeting of vehicles containing loose aggregate;  early stabilisation of earthwork surfaces;  keeping stockpiles away from the site boundary;  use of mobile or fixed spray units to suppress dust;  fixed wheel washing at all exits; and  the installation of an earth bund north of the Doggets property 1.6.38 With the adoption of the EMMP, all construction impacts from dust and emissions are expected to be reduced to minor or negligible adverse. 1.6.39 Emissions to air during operations, from both the power station and associated transport, are expected to be trivial and the overall impact is considered to be negligible adverse. i) Socio-Economic Impacts 1.6.40 Socio-economics groups together the potential effects that the development could have on the day to day quality of life of people and communities. It covers issues such as:

 demographic change: changes in the local population level caused by the temporary or permanent introduction of project staff and their families;  employment change: both direct site employment and indirect employment arising from increased demand for local goods and services;  expenditure effects: spending by the workforce and from project contracts;  accommodation pressures: demand for temporary and permanent housing with implications for prices and residential property values; and  local social conditions: pressures on education, health and crime. 1.6.41 The great majority of the predicted socio-economic impacts are positive but EDF Energy is proposing to develop a range of practical measures to ensure that the local community derives as much benefit as is practicable from the construction and operation of Hinkley Point C and that any negative impacts are mitigated and minimised. 1.6.42 Key measures will include:

 Employment: EDF Energy will prepare a Construction Workforce Development Strategy which will set out how the project will maximise employment and skills opportunities for local people. Working in partnership with a local training provider and national skills bodies, EDF

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 11 ENVIRONMENTAL APPRAISAL: SUMMARY Energy will establish a construction skills training centre and a construction apprenticeship learning hub.  Accommodation: A site campus will be provided on-site at Hinkley Point C of up to 700 units; centres in Bridgwater centres in Bridgwater will be phased to cope with demand to provide places of up to 150 and 1075 units respectively. Where appropriate, the accommodation will be sited and designed to provide long term benefit to the local community after the construction period; for example, a Bridgwater centre could provide residential or management centre facilities for Bridgwater College.  Wider economic benefits: EDF Energy is designing a procurement strategy to ensure that local firms are able to take advantage of the opportunities that the investment at Hinkley Point C will bring. Sourcing goods and services in the area local to Hinkley is part of EDF Energy’s overall business strategy and it has been estimated that the construction and operation periods may on average put £100m pa and £40m pa respectively into the local economy. This should enable existing businesses to grow and develop and could help to attract high value and knowledge based industries to the area.  Crime and policing: Experience from the development of other power station sites, both in the UK and in France, indicate that very low levels of non-local behavioural issues may be expected. Nevertheless, EDF Energy will work with the local police forces to prepare a Police Resourcing Strategy and make contributions to the cost of employing additional police officers during the construction period. 1.6.43 EDF Energy’s studies, and the practical measures that are being developed, show that there is scope to enhance the substantial benefits of the project, especially for employment and wider economic impacts, and to mitigate the potential negative impacts on accommodation, local services and local quality of life. The majority of the impacts are positive, but with the introduction of the mitigations described, it is considered that any remaining negative impacts are minor to negligible. j) Impacts on the natural and built environment 1.6.44 The construction and operation of Hinkley Point C has the potential to impact on different aspects of the natural and built environment including:

 terrestrial ecology;  marine ecology;  soils and land use;  contaminated Land;  groundwater;  surface water;  marine water and sediment quality;  amenity and recreation; and  historic environment. 1.6.45 EDF Energy has commissioned studies to investigate the potential impacts and, where appropriate, propose mitigations. The detail of this work is set out in the individual Environmental Appraisal chapters. A brief summary of the most significant environmental effects and their proposed mitigations is set out here. k) Terrestrial Ecology 1.6.46 The development of Hinkley Point C has the potential to affect habitats and species directly (e.g. through land take and removal of habitats) and indirectly (e.g. through disturbance) with the impacts potentially extending beyond the Development Site boundaries.

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ENVIRONMENTAL APPRAISAL: SUMMARY 1.6.47 Part of the Hinkley Point C Development Site comprises the Hinkley County Wildlife Site (CWS), which is considered to be of regional or county importance. It consists of a network of species rich scrub, coastal grassland and broad-leaved woodland with ponds and areas of improved grassland. Approximately 68% of this site will be lost to power station construction, but the plant layout has been designed such that there will be no land take from the mosaic of habitats to the east of Wick Moor Drove. This will enable much of the botanical interest of the Hinkley CWS to be retained including all reed bed, the majority of the scrub and a large proportion of the more botanically diverse grassland. To mitigate the habitat loss, a mosaic of habitats will be created. 1.6.48 The majority of hedgerows and woodland within the Development Site will mostly be lost although the hedgerows running east – west across the centre of the site will be retained as a habitat corridor to enable the continued movement of bats, invertebrates and birds across the development area. These are established hedgerows and well connected to the wider landscape. 1.6.49 The foreshore, mudflats and intertidal habitat immediately to the north of the Development Site are designated as a Ramsar Site, a Special Protection Area (SPA), a Special Area for Conservation (SAC) and a Site of Special Scientific Interest (SSSI) for the internationally and nationally important habitats and wildlife species present. Part of the SPA and SSSI extend inland, taking in Wick and North Moor which are adjacent to the eastern edge of the Development Site. 1.6.50 The most potentially significant effect on these habitats, which are outside the Development Site (except for the construction of the cooling water culverts and temporary jetty), is disturbance to the internationally and nationally important numbers of birds that feed and roost in the area, both overwinter and on migratory passage. The construction activities with the greatest potential to cause disturbance and which are in the closest proximity to known areas of bird use are expected to be:

 piling works for the temporary jetty;  use of jack up rigs, barges etc during construction of the temporary jetty; and  machinery and foreshore movement of people during construction of the sea wall. 1.6.51 Generally it is accepted that birds tend to be more affected by the presence of people rather than noise from equipment. Disturbance is usually observed to be small scale (i.e. short distance) displacement and effects are usually temporary; there are very few examples where disturbance has caused birds to permanently vacate a site. 1.6.52 The main mitigation of impact on bird populations has been to avoid areas within 1km of the Development Site that hold large numbers of foraging birds throughout the year. Steart Flats to the east of the built plant is the most sensitive area and the siting of the temporary jetty to the west of the site has significantly reduced the potential for disturbance. 1.6.53 There are a number of measures that will be taken to limit disturbance without compromising construction. These include:

 avoiding noisy activities, such as piling works and foundation excavation, at night;  piling work subject to soft start up; and  jetty to be constantly lit with directional lighting to limit light spill. This allows birds to become habituated to the lighting rather than disturbed every time it is turned on. 1.6.54 With the adoption of the mitigation against habitat loss and disturbance of birds, all impacts on terrestrial ecology are considered to be minor to negligible adverse.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 13 ENVIRONMENTAL APPRAISAL: SUMMARY l) Marine Ecology 1.6.55 The Severn Estuary, which adjoins the Hinkley Point C Development Site, has one of the largest tidal ranges in the world, reaching in excess of 13m upstream at Avonmouth. Biologically the invertebrate fauna is impoverished in both species and abundance due to the powerful tidal shear forces and the regular resuspension of bottom sediments. There are no macro algae to be found in the sub tidal zone due to a predominance of muddy sediments and high levels of water turbidity. 1.6.56 The intertidal zone near Hinkley Point is considered to be an important foraging and nursery area for a broad range of fish species. Few fish complete their life cycle within the estuary and mature fish tend to move offshore to breed. Migratory fish such as Atlantic salmon, twaite shad, allis shad, river lamprey, sea lamprey, sea trout and European eel use the Estuary and are one of the special features which have led to the designation of the Severn as an internationally important wetland under the Ramsar Convention. 1.6.57 Impact on the marine environment from construction activities could arise in the following ways:

 sub tidal habitat loss from the construction of the vertical shafts for the cooling water system;  intertidal habitat loss from the construction of the temporary jetty;  intertidal habitat change as a result of the construction of the seawall;  discharges associated with the drilling of the horizontal tunnels; and  noise and vibration impacts on fish and marine mammals. 1.6.58 The implementation of general good practice construction measures, including adherence to a waste management plan, delimiting buffer zones, designated no–go areas and the provision of personnel training will ensure that all potential impacts can be considered to be minor to negligible adverse. However other specific mitigation measures have also been considered including:

 containment and treatment of drilling mud and associated chemicals; and  soft start to piling operations to allow fish to move out of the area before normal pile noise levels are reached. 1.6.59 Impact on the marine environment from operational activities could arise from:

 chemical discharges including biocides to prevent marine fouling of the cooling water system;  thermal impacts from the discharge of warmed cooling water; and  entrainment and impingement impacts on fish and other organisms being drawn into the cooling water system. 1.6.60 Studies have indicated that these impacts, in the context of the Severn Estuary, are expected to be minor or negligible adverse with the following exceptions:

 entrainment and impingement impacts on fish; for most fish species the impact is considered to be minor adverse, but there is some concern that the impact on European eel, river lamprey and sea lamprey may be more significant. The feasibility of mitigating this impact is being investigated; and  thermal imparts form discharge of warmed cooling water; these will be higher significance with HPC and HPB operating at the same time.

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ENVIRONMENTAL APPRAISAL: SUMMARY m) Soils and Land Use 1.6.61 The majority of land within the Hinkley Point C Development Site is in agricultural use (arable and grazing) with some areas of woodland and scrub. A review of historical maps and plans has identified that the land has remained as greenfield agricultural land since the earliest available map was published in 1886. The majority of the land (86%) is of moderate to poor agricultural quality. The remainder (14%) is classified as Best and Most Versatile Land (BMVL) grade 3a. 1.6.62 The primary impact on soils and land use will be the loss of land and change of land use from construction of the power station. Of the total 168ha site area, approximately 61ha will be permanently lost to constructed features. Post construction, 107ha would be restored to agricultural land, woodland, scrub hedgerow and wetland habitats. 1.6.63 Taking into account the relatively small scale loss of BMVL, and the less than 0.1% overall loss of grade 3 land in a Somerset context, the impact is considered to be of minor adverse significance. n) Contaminated Land 1.6.64 A series of intrusive borehole investigations was carried out on the Hinkley Point C Development Site to determine the presence or absence of non-radiological and radiological contamination. Historically, the majority of the land was in agricultural use, although from 1958 the eastern part of the site has been used as a fabrication and construction area during the construction; firstly of Hinkley Point A and subsequently of Hinkley Point B power stations. 1.6.65 The studies have confirmed a very low likelihood of any significant non-radiological or radiological contamination across the great majority of the site. The exception is the eastern part of the site where there were a number of discrete areas of hydrocarbon contamination and a number of small areas where asbestos contaminated materials had been buried. 1.6.66 To mitigate the risk from this localised contamination further work will be carried out to identify the precise locations of any asbestos contaminated materials and the sources of other contaminants, so that they may be removed prior to the construction works starting. On the basis of this mitigation, and the studies and investigations undertaken to date, it is considered that the potential risk of harm to people and wildlife as a result of exposure to contaminants during the construction period is negligible to minor. o) Groundwater 1.6.67 The Hinkley Point C Development Site is underlain mainly by rocks belonging to the Lower Lias (of lower Jurassic age). The area around the southern boundary is underlain by faulted older Permo – Triassic rocks of the Penarth Group (subdivided into an upper formation and a lower Westbury formation), the Blue Anchor formation and Mercia Mudstones. There is likely to be a further fault bringing another outcrop of the Penarth Group rocks further north within the Development Site. 1.6.68 The Environment Agency has classified the water resource within the Lower Lias rocks as Secondary A, i.e. permeable layers capable of supporting water supplies at a local rather than strategic scale, and in some cases forming an important source of base flow to rivers. The Lilstock formation is also likely to be Secondary A whilst the Westbury and Blue Anchor formations and the Mercia Mudstones are Secondary B due to their limited yield of groundwater from minor fractures or thin permeable horizons. 1.6.69 The main impacts of development on the groundwater conditions are likely to be:

 dewatering;  modification of the natural groundwater regime during the operational period; and

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 15 ENVIRONMENTAL APPRAISAL: SUMMARY  potential contamination of groundwater during both construction and operational periods. 1.6.70 Assessment work has indicated that the only potentially significant effects relate to the control of the dewatering cone of depression and the influence of this on the movement of potentially contaminated groundwater into the aquifer and the baseflow conditions of the Holford Stream. Mitigation options include hydraulic control, where groundwater movements can be reversed by recharging the aquifer to prevent any contamination reaching the abstraction and engineered control where a temporary (ground freezing) or permanent (grout curtain) barrier is put in place. 1.6.71 Based on the availability of appropriate mitigations and the assessment work undertaken, it is considered that it is unlikely that there would be any significant residual effects. p) Surface Water 1.6.72 The surface watercourses of the Hinkley Point C Development Site can be characterised as follows:

 A connected series of intermittently flowing agricultural ditches that drain the west of the site and ultimately discharge water to the foreshore through an unnamed watercourse, now referred to as the Hinkley Point C drainage ditch.  Perennial streams in and to the south of the site. These comprise the Holford Stream which rises and flows eastwards and is culverted under the C182 and flows through Wick Moor to converge with West Brook. Bum Brook flows eastwards and has two tributaries, Bailey’s Brook and Stogursey Brook. It splits into two channels at Wick (East and West Brook). These then flow parallel with each other before converging immediately upstream of the Great Arch Sluice through which the watercourse discharges, via an 80m long culvert to the foreshore to the immediate west of Stolford Point. 1.6.73 During the preliminary works phase, the Holford stream will be culverted along its entire reach within the Development Site. This will allow the Holford valley to be levelled and terraced into a series of platforms, to provide space for the stockpiling of material from excavation. 1.6.74 The construction period surface water drainage arrangements will comprise:

 construction of a drain to intercept the upper area of the Hinkley Point C drainage ditch catchment;  construction of three main spine drains to serve the main part of the site;  construction of either a single or three outfalls to the Severn Estuary;  culverting of a section of the Holford Stream; and  construction of two outfalls to the Holford Stream and the Bum Brook to serve the southern part of the Development Site. 1.6.75 There is potential for the water quality status of these watercourses to be affected during construction by suspended sediments from surface water runoff and accidental spillages of chemicals. Mitigation measures will be employed, including the creation of buffer zones along watercourses, the use of sediment fences to reduce water flow and trap sediment on the bare engineered slopes prior to stabilisation, and the use of catchpits to remove suspended solids and contaminants. An environmental monitoring strategy will be established for all elements of the surface drainage system. q) Marine Water and Sediment Quality 1.6.76 The River Severn is the major freshwater input to the estuarine system, providing approximately a quarter of the total flow to the Severn Estuary and Bristol Channel. The Severn Estuary has historically received large loadings of contaminants from sewage and industrial outputs. Historical contaminants are highly varied and include metals, hydrocarbons, biocides, mineral

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ENVIRONMENTAL APPRAISAL: SUMMARY acids pesticides and radionuclides. More recently, studies have reported a decreasing concentration trend for the majority of dissolved metals and the most recent water quality monitoring results indicate that all chemicals for which Environmental Quality Standards (EQS) exist were present in average concentrations below the action threshold value. 1.6.77 The marine waters of Hinkley Point are characterised by high concentrations of suspended solids arising from sediment mobilisation by seabed scouring flows and tidal currents as a result of the high tidal range. 1.6.78 Potential impacts on marine water quality from the development of Hinkley Point C could arise from:

 discharges to the foreshore from surface water drainage;  construction of the temporary jetty resulting in sediment disturbance;  construction of the sea wall;  discharge of wastewater from horizontal tunnelling works; and  discharges and sediment mobilisation from vertical drilling for the cooling water culverts. 1.6.79 Potential impacts from the operational period could include:

 thermal discharges from cooling water;  discharge of process water chemicals; and  disturbance of marine sediments associated with scour from the cooling water system infrastructure and from maintenance dredging around intake structures. 1.6.80 The assessment studies indicate that there is a low risk of non-compliance with existing regulatory water quality thresholds. Although certain thermal criteria are not met, this is very limited in extent. The temperature increases are localised and biological impacts would be insignificant. r) Landscape and Visual Impact 1.6.81 The Hinkley Point C Development Site is considered to fall within “National Character Area 142: and Moors” which has the following characteristics:

 flat open landscape of wet pasture, arable and wetland divided up by wet ditches or “rhynes”;  absence of dispersed farmsteads or any buildings on levels and moors. Nucleated settlements on ridges/islands;  surrounded, and divided up by low hills; ridges and islands which form distinctive skylines; and  sparse tree cover on levels and moors contrasting with woodland, hedges and orchards of surrounding hills. 1.6.82 The principal impacts of construction and operation will be the loss of existing landscape features from the Development Site (grassland, small woods, hedgerows and streams), and the increase in the amount of built form adjacent to the existing Hinkley Point nuclear power stations. 1.6.83 Visual impact is a function of the sensitivity of the landscape, the magnitude of the change and the visibility of the development. The visibility of the site is principally restricted by the undulating topography and, to a lesser extent, existing mature woodland. Views from the east are predominantly from the coastline, whilst from the west they are also available from some of the higher but more distant areas on the eastern fringes of Exmoor National park. From the south and south-west, low hills obscure the site from distant locations but provide good views closer to the site. Views from the north are from the sea.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 17 ENVIRONMENTAL APPRAISAL: SUMMARY 1.6.84 The areas of highest sensitivity to visual impact are considered to be the coastline, Area of Outstanding Natural Beauty (AONB), Exmoor National Park and the lowland hills around the site. 1.6.85 Mitigation of impacts will be through the development of an overall landscape strategy which will include the following elements:

 retention of some valuable landscape features within the Development Site such as Green Lane along with hedgerows around the perimeter of the site wherever this is possible;  advance planting as part of the site preparation works in the southwest corner of the site adjacent to Bum Brook and along Benhole Lane;  planting and bunding north of Doggets as part of the construction of the accommodation campus;  creation of vegetated screening bunds adjacent to the western boundary of the completed development; and  screening views of the lower buildings within the development through screen planting around the development boundary. s) Recreation and Amenity 1.6.86 Walking, wildfowling, fishing, bird watching and horse riding are the main sporting and recreational activities carried out around the Hinkley Point C Development Site. With the exception of walking and fishing, these are carried out in generally restricted areas and in small numbers. 1.6.87 There are around 50km of public rights of way in a 3km radius of the site connected to the Hinkley Point area by road or other footpaths. These include the West Somerset Coastal Path which links the trail at Steart on Bridgwater Bay with the South West Coastal Path National Trail at Minehead. 1.6.88 Impact on recreation and amenity will principally be through the closure or diversion of public rights of way either on a temporary or permanent basis. The West Somerset Coastal Path will need to be closed for between 18 months and three years for construction of the temporary jetty and coastal defences. Approximately 8,200m of public rights of way (PROW) are expected to be affected. 1.6.89 Mitigation measures have been developed in association with local residents, and the District and County Council officers. The range of measures is extensive and includes:

 the development of a temporary footpath around the boundary of the construction area to create a linked circular PROW around the entire site;  permanent provision of a bridleway around the outer boundary of the Development Site; and  improved signposting, replacement of stiles with kissing gates and upgrading of paths. 1.6.90 No significant impact is expected on other recreational users and, with the implementation of the mitigation measures, it is considered that the overall effect on recreation and amenity will be reduced to minor to moderate adverse. t) Historic Environment 1.6.91 There are no Scheduled Monuments, Listed Buildings, Conservation Areas, Registered Parks and Gardens, Registered Battlefields or ancient woodlands within the Development Site. There are a number of hedgerows that meet the archaeological and historical criteria defined in the Hedgerow Regulations 1997.

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ENVIRONMENTAL APPRAISAL: SUMMARY 1.6.92 There is one Scheduled Monument, Wick Barrow (also known as Pixies Mound), which is 50m outside the site boundary to the east of Wick Moor Drove. 1.6.93 Archaeological remains and features known to occur within the site include:

 Romano-British settlements to the south and east of Benhole Farm;  a trackway, recorded on all historic maps going back to 1614, which occupies a ridge and runs east – west across the site; and  a Bronze Age ditched enclosure and cremation site to the south of the site. 1.6.94 Soil stripping and reprofiling will effectively destroy the archaeological remains within the Development Site and, following discussion with Somerset County Council, the following mitigation measures are proposed:

 The western, and best preserved, part of the trackway will be preserved in situ with the eastern section being preserved by record.  Remaining features will be preserved by record. This will comprise a staged programme of archaeological excavation and recording, followed by appropriate post excavation works including assessment, analysis, publication and archiving.  The setting of the Scheduled Monument, Wick Barrow, will be affected by the development and a Monument Management Plan will be prepared to ensure the long term preservation of the monument. 1.6.95 With the adoption of the mitigation measures, it is considered that the residual impacts on the historic environment will have been reduced to minor adverse.

1.7 Potential Environmental Impacts and Mitigations: Off-Site Associated Development

1.7.1 This section summarises the potential environmental impacts that may arise from the implementation, including the eventual removal where appropriate, of the Off-Site Associated Developments. In each case, only those impacts which are regarded as moderate or greater before mitigation are discussed. More detailed treatment of the environmental impacts is contained within the main body of the Environmental Appraisal. a) Bridgwater Accommodation Campuses 1.7.2 Two sites have been identified for the provision of accommodation campuses in Bridgwater. BRI-A is currently occupied by a former cellophane factory to the north and a playing field to the south. The entire area of BRI-C was part of a former clay pit that was backfilled with a variety of wastes in the 1960s through to the 1970s. The site was subsequently restored and is currently a practice rugby pitch associated with the Bridgwater and Albion Rugby Club. 1.7.3 The principal environmental impacts are:

 Permanent loss of the practice rugby pitch at BRI-C. This loss will be mitigated by the provision of a pitch elsewhere. Details will be provided in the application for Development Consent.  Impact of noise levels from earthworks and site preparation along the southern boundary of BRI-A and the eastern boundary of BRI-C. Specific mitigation would include the erection of standard hoardings, restriction of working hours and the housing of continuous noisy plant in acoustic enclosures. Further site-specific measures will be set out in the Environmental Management and Monitoring Plan (EMMP).

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 19 ENVIRONMENTAL APPRAISAL: SUMMARY 1.7.4 There are no other potential unmitigated environmental impacts of moderate or greater adverse consequence. b) Cannington Bypass 1.7.5 A single carriageway bypass to the west of Cannington is proposed to reduce the volumes of traffic, associated with the development of Hinkley Point C, travelling through the village. It links with the A39 to the south-west of Cannington, heading north through agricultural land to the west of the village, linking with Chad’s Hill to the north of the village. 1.7.6 Principal environmental effects are:

 potential impact on protected bird species and bat populations. These will be mitigated through the adoption of landscaping and creation of new habitat and the installation of underpasses to facilitate the movement of species across the bypass;

 long-term vehicle emissions of NO2 from bypass traffic will increase significantly. However

there is expected to be a reduction in NO2 levels within the centre of Cannington. Mitigation is not therefore proposed as the bypass is itself providing mitigation for air quality impacts within the centre of Cannington.  impact on the landscape through changes to the character of the site arising from loss of agricultural land, the introduction of construction lighting and the introduction of man-made structures. This will be mitigated through the development of a landscape strategy that will provide screening from viewpoints, including the planting of new hedgerows and trees and the protection of existing features of value;  there will be a permanent loss of 8.8ha of best and most valuable agricultural land (BMVL) i.e. grades, 1, 2, and 3a. There is no mitigation for this loss.  short term noise disturbance from construction and long-term noise disturbance from operation of the bypass at Knapp Farm, Withiel Farm and residential properties on Withiel Drive. However, there will be a reduction in noise impact for many properties within Cannington village once the bypass is operational. Mitigation will include restrictions to working hours during construction and the installation of acoustic barriers for the most affected properties. 1.7.7 There are no other unmitigated environmental impacts of moderate or greater adverse consequence. c) Cannington Park and Ride Facility 1.7.8 The site identified for a park and ride facility lies in generally open countryside to the south of Cannington, between the A39 and the village. The main land use is permanent pasture used for grazing dairy cattle, with some small areas of woodland/scrub and hedges and open ditches forming the field boundaries. 1.7.9 The principal environmental impacts are:

 Impact on the landscape during construction from changes to the character of the site arising from loss of agricultural land, the introduction of construction lighting and the introduction of man-made structures. This will be mitigated through the development of a landscape strategy that will provide screening from viewpoints, including the planting of new hedgerows and trees and the creation of wetland areas.  Potential impact on the agricultural field drainage system with the risk of waterlogging of soils of adjacent properties. This will be mitigated by inspection and mapping of field drainage and the installation of any new drainage system in advance of site preparation works operations.

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ENVIRONMENTAL APPRAISAL: SUMMARY 1.7.10 There are no other unmitigated environmental impacts of moderate or greater adverse consequence. d) Combwich Wharf and Freight Logistics/Storage Facility 1.7.11 EDF Energy is proposing the refurbishment of Combwich Wharf to allow for the delivery of freight by water together with an associated freight logistics/storage facility. The site is currently an existing wharf with adjacent land in agricultural grazing use. 1.7.12 The principal environmental impacts are:

 Potential hazards to water based recreation (boating and sailing) associated with the installation of new infrastructure at Combwich Wharf. This would be mitigated by issuing a Notice to Mariners to inform users of the River Parrett of the construction of the proposed development; local recreation clubs would be issued with a similar notice providing details of any potential hazards.  Changes in the character of the site and the impact on landscape associated with the loss of agricultural land and the introduction of hardstanding and other man-made structures. This would be mitigated through a landscape mitigation strategy which would: o create native tree and shrub planting within the site; o create grassland areas; o create balancing ponds; and o locate the security fences as close to the edge of the hardstanding and access roads as possible, leaving proposed landscaping and ditches connected to the surrounding habitat.  The site of the Romano-British port and medieval harbour would be affected by the refurbishment of the Wharf. Previous development is likely to have destroyed much of these sites but a precautionary approach has been adopted. If remains of these assets survive then suitable mitigation will be agreed with the statutory consultees. 1.7.13 There are no other unmitigated environmental impacts of moderate or greater adverse consequence. e) Williton Park and Ride 1.7.14 The site identified for a park and ride facility is located on the western fringe of Williton. The site is bounded by the A39 to the south and Mamsey Lane to the east and is currently used for agricultural purposes. 1.7.15 The principal environmental impacts are:

 Impact on the landscape during construction, in particular from local viewpoints and the lighting impact which would be visible from the elevated areas of the Quantock Hills AONB and Exmoor National Park. Mitigation will involve the development of a landscape strategy to provide screening.  Impact on the rural setting of off-site Scheduled Monuments at Battle Gore Barrow Cemetery, St Peter churchyard cross and the adjacent Grade II* listed Church of St Peter. The site would be visible to the north-west from the remains of the Scheduled and Grade II* Listed churchyard cross and the adjacent Grade II* Listed Church of St. Peter. Mitigation would be through specific landscape screening proposals. 1.7.16 There are no other unmitigated environmental impacts of moderate or greater adverse consequence.

HINKLEY POINT C PRE-APPLICATION CONSULTATION – STAGE 2 | 21 ENVIRONMENTAL APPRAISAL: SUMMARY f) Junction 23 Park and Ride and Freight Logistics Facilities 1.7.17 The site, which has been identified for a park and ride facility and freight logistics facility, is located approximately 500m west of Junction 23 of the M5. It is currently used for agricultural purposes, and is bordered by agricultural land to the west and south (with the River Parrett beyond), and existing industrial development to the east and north (with the A38 beyond). 1.7.18 There are no unmitigated environmental impacts of greater than minor adverse consequence associated with this site. This is primarily a reflection of the semi-industrial location of the site and the lack of sensitive receptors in the surrounding area. g) Junction 24 Park and Ride and Freight Logistics Facilities 1.7.19 The site, which has been identified for park and ride and freight logistics facilities, is located on land approximately 300m to the west of Junction 24 of the M5. It is currently used for agricultural purposes and is bordered by agricultural land to the north and west, scattered development and agricultural land to the south, and by the A38 to the east. 1.7.20 The principal environmental impacts are:

 Impact on the landscape during construction especially given the location of the development on a prominent unvegetated ridge in an open landscape. Construction lighting would have a potentially adverse impact on the local landscape as well as the elevated areas of the Lowland Hills Area and Quantock Hills AONB. Mitigation will involve the development of a landscape strategy to provide screening.  Potential impact on the agricultural field drainage system with the risk of waterlogging of soils of adjacent properties. This will be mitigated by inspection and mapping of field drainage and the installation of any new drainage system in advance of site preparation works operations.  There will be a permanent loss of 5.4ha of best and most valuable agricultural land (BMVL) i.e. grades 1 and 2. There is no mitigation for this loss.  Short-term noise disturbance during the construction of site roads and parking bays to properties on the opposite side of the A38 from the facility. Adherence to typical construction working hours, during which existing road traffic noise from the A38 dominates, would reduce the overall potential for disturbance. 1.7.21 There are no other unmitigated environmental impacts of moderate or greater adverse consequence.

1.8 Potential Environmental Impacts and Mitigations: Cumulative Impacts with other Major Developments

1.8.1 The potential for cumulative environmental impacts to arise needs to be taken into consideration in the full scope of an environmental assessment. Cumulative impacts can be broadly defined as additive or interactive. Additive impacts are those in which change in an environmental receptor is added to from another change. Many small effects on one sensitive receptor could add up to an overall significant effect even if they are individually insignificant. An example could be the additive impact from noise upon local residences. An interactive impact is caused by the interactions of different impacts on the same sensitive receptor, e.g. the interaction of noise disturbance and light pollution and light pollution on bat foraging. 1.8.2 EDF Energy has undertaken a review of the potential for cumulative impacts and this is set out in Section 4 of the Environmental Assessment. This considers the potential for and significance

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ENVIRONMENTAL APPRAISAL: SUMMARY of cumulative effects within the project (i.e. effects that may arise between different components of the project) and those effects with other plans or projects in the wider area. Essentially, most of the impacts of the development are confined to the immediate vicinities of the individual project components and the potential for cumulative effects to occur within the project is therefore limited. Some additive effects may occur in the Cannington area during construction of the park and ride, bypass and refurbishment of Combwich Wharf. Similarly, there may be additive effects with regard to the operational aspects of the accommodation in Bridgwater. 1.8.3 A review of other plans and projects that could potentially interact with the HPC project suggests that there are several major developments within the wider area of the Severn Estuary that may have the potential for a cumulative environmental impact with HPC. These include the proposed nuclear power station at Oldbury, the decommissioning of Hinkley Point A and Hinkley Point B nuclear power stations, the National Grid 400kv transmission line to Hinkley, the Bristol Deep Sea Container Terminal and proposed managed realignment project at Steart. These have been assessed with respect to their potential for spatial and temporal overlap of effects with the HPC project. 1.8.4 While it is apparent that there are a number of parameters where cumulative effects could occur, it is considered unlikely that the majority of these effects are of greater significance than those determined for the HPC project in its own right. This is largely due to limited spatial interaction between the projects and where this does occur the interactions are either weak or of a temporary nature. The main areas where effects could occur that would be of significance are with respect to the marine environment and the landscape. With regard to the landscape impact, the effect of the National Grid project within the local sphere of influence of HPC has been taken into account in the landscape cumulative assessment work. The cumulative impact of the Hinkley Point C Development and National Grid’s overhead line proposals would be of local significance from a limited number of viewpoints and predominantly in the short distance. Marine impacts, while confined to the immediate vicinity of the HPC may be additive with those of other projects. Further work is being progressed specifically to look at the impact of the thermal effects of the cooling water system for HPC and this work will assist in determining whether such a cumulative effect is of significance. Overall, it is clear that the socio-economic effects of all of the projects considered are of significant benefit to the wider region.

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