FUNDAMENTAL SAFETY OVERVIEW VOLUME 3: ENVIRONMENTAL IMPACT CHAPTER E: SUMMARY OF ENVIRONMENTAL AND HEALTH EFFECTS

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1 : SUMMARY OF ENVIRONMENTAL AND PAGE : 1 / 10 SUMMARY OF ENVIRONMENTAL AND 1. INTRODUCTION In Volume 3 the environmental and health effects associated with a conceptual design of the EPR are identified. This generic assessment is based on a detailed sitespecific environmental and health assessment for the EPR to be constructed at Flamanville, France on the same site as two existing nuclear reactors (Units 1 and 2). The Flamanville 3 EPR assessment identified environmental and health effects associated with the site and design, measures to mitigate impacts, and residual effects. The impacts that are associated with the EPR design itself rather than the specific Flamanville site are identified in this volume and put into an UK context. Environmental and health effects are summarised below by various aspects of the environment. 2. MARINE ENVIRONMENT 2.1. CONSTRUCTION During the construction phase, the following potential impacts upon the marine environment have been identified: Excavation, dredging, drilling, piling, blasting and immersion of concrete blocks will be considered for construction and installation of infrastructure associated with cooling water intake and discharge. Each of these activities can give rise to suspended soils, solid waste (rock, sand, mud etc) and vibration which may impact upon marine ecology, hydrology and sedimentology. The following substances could be discharged into the sea during construction: phosphates, iron, morpholine, hydrazine, bromoform and other oxidants. Construction can result in elevated levels of suspended solids in surface water run off into the sea. Suspended solids can have a significant impact upon intertidal zone species such as bivalve molluscs and filter feeders as the suspended material may comprise abrasive material which causes irritation. Due to a wide range of site specific factors such as geology and material selection and construction methodology, it is not possible to accurately predict the impact of discharges to sea during the construction phase. However, with appropriate mitigation measures in place, significant impacts on the marine environment are not anticipated due to construction of the EPR.

2 : SUMMARY OF ENVIRONMENTAL AND PAGE : 2 / OPERATION Approximately 67 m 3 /s of water is continuously required for cooling the EPR unit at Flamanville 3. A detailed assessment of the impact of water abstraction must be undertaken on a site specific basis. Such an assessment should include (but not be restricted to) availability of water, ecology of the source water environment, topography, local geological and hydrological conditions and climate. Cooling water is discharged back into the sea. The discharge rate has been estimated at 58 m 3 /s at a speed of 4 m/s which is a high discharge rate capable of causing disturbance to the sea bed, fauna and flora. For the assessment of the generic UK EPR design, it is assumed that the abstracted cooling water will also be discharged back to the source environment at a rate of 4 m/s. It is not possible to accurately predict the impact of such a discharge at a generic level; therefore a detailed assessment must be undertaken once a designated site has been selected. Such an assessment should include (but not restricted to) the ecology of the receiving environment, local geology and hydrology, hydrodynamics, navigation and climate. Thermal discharges from Flamanville 3 were deemed to have no impact on the marine environment. However, the average temperature of the Flamanville coastal seawaters is warmer that than most coastal waters around the UK. As such, a site specific assessment must be carried out in order to determine the impact of thermal discharges upon the local marine environment. The operation of an EPR will give rise to a range of liquid waste effluents from a range of processes. Some effluents may be subjected to treatment prior to discharge from the plant whereas other effluents may be exported off site for disposal at water treatment plants. As part of the assessments carried out for Flamanville 3, comparisons were made between calculated levels of substances after dilution and French seawater quality targets. In assessing the impact of a UK EPR, the concentration of substances after dilution will be compared to the Environmental Quality Standards for Saltwater and relevant European Directive targets. At Flamanville, studies showed that the ecology of the coast was not greatly impacted by the development of the EPR. In particular, zooplankton was noted as not being affected and although localised disturbance of crustaceans was noted, the overall impact upon marine zoology was concluded to be negligible. 3. TERRESTRIAL ENVIRONMENT 3.1. CONSTRUCTION Most developments have the potential to cause pollution of soils on a local scale during the construction phase (e.g. hydrocarbons from vehicles, dust, and spillages of materials). Large scale construction of complex facilities is more likely to utilise a wide range of potentially contaminating substances which can impact on geology and soil quality. The main effect of such contamination is the subsequent effect upon groundwater and human health.

3 : SUMMARY OF ENVIRONMENTAL AND PAGE : 3 / 10 Industrial development has the potential to impact natural habitats. Of particular concern are impacts to designated habitats such as Sites of Special Scientific Interest (SSSI) and Special Protection Areas (SPAs). SSSIs and SPAs range from wetlands to sand dunes, mountains and fens. In order to quantify the impact of construction activities upon these sensitive areas, a detailed site specific study must be completed to assess how the site specific sensitive features may be impacted. For example, a SSSI may be designated because of its floral biodiversity and may therefore be sensitive to smothering by dust or litter. An SPA may be designated because of the abundance of food sources for wintering birds and may therefore be sensitive to disturbance caused by noise and vibration. However a site specific assessment must be undertaken in order to conclude whether construction of the UK EPR will have an impact upon natural habitats. Construction of the UK EPR will require a large quantity of raw material and can potentially give rise to an equally large quantity of waste OPERATION The primary terrestrial impacts associated with an EPR are expected to occur during the construction phase. The primary impact on the terrestrial environment from operation of the UK EPR will be from waste arisings and unplanned discharges of effluents onto land. Structures, plant and machinery will be built to strict building control standards. Pollution Prevention and Control Regulations (PPC) regulatory specifications and Best Available Techniques (BAT) will minimise the potential for unplanned discharges to ground. The impact upon land quality of unplanned discharges is therefore considered to be very low. 4. FRESHWATER 4.1. CONSTRUCTION During the construction phase of the EPR, the following potential impacts upon the freshwater environment have been identified: groundwater intrusion into pits, trenches or tunnels, contamination of surface runoff and/or groundwater due to site activities, turbidity and flow restrictions in water courses during construction of water intake structures, abstraction of water for site use. Groundwater which enters pits or other construction works will be checked for contamination (i.e. oil sheen) and disposed appropriately. The potential for spills and contaminated runoff will be minimised through good construction practices. The Flamanville 3 EPR did not require any intake constructions in freshwater nor any freshwater abstraction. If freshwater is utilised for sanitary purposes or other uses at a UK site, these issues will need to be addressed.

4 : SUMMARY OF ENVIRONMENTAL AND PAGE : 4 / OPERATION During the operational phase of the EPR, the following potential impacts upon the freshwater environment have been identified: contamination of surface runoff and/or groundwater due to site activities, abstraction of water for site use. Although these impacts may differ in scale from those discussed for the construction phase the designs and consequences due not differ significantly from those previously discussed. The environmental assessment for the Flamanville 3 EPR concluded that, with the good site practices in place, no significant impacts are expected during construction or operation on surface water or groundwater regimes. 5. AIR QUALITY AND CLIMATE 5.1. CONSTRUCTION Potential effects on local air quality during the construction phase include the generation and deposition of dust and exhaust emissions associated with plant used on site, the transportation and delivery of materials to the site, and the removal of any materials arising as a result of any required demolition or earth works. Dust suppression measures will be implemented as needed. A transport plan will be developed with measures to reduce the number of deliveries to site. Potential sources of odorous emissions were identified within the Flamanville 3 assessment as exhaust gases from plant used on site and formaldehyde. The assessment concludes that on the basis of the low quantities emitted and the fact that odours will be localised and rapidly dispersed, it is unlikely that they will be noticeable OPERATION Traffic levels on roads in the vicinity of the installation will increase as a result of the delivery of raw materials to the site, the transportation of employees to site and the removal of waste. The impact of the increases in traffic flows is site specific and is influenced by the existing air quality in the local area and the percentage increase in vehicles flows on the highway network. The Flamanville site includes four main backup electricity generators of 7 MWe and a further two final emergency generators of 2 MWe. The generators are only likely to be used for a few hours per year for periodic tests or in the event of power interruptions. The Flamanville 3 assessment concludes that on the basis of the very short operational period of the generators, exhaust emissions associated with these emissions are not considered to be significant. Formaldehyde and carbon monoxide will be produced during unit maintenance operations following the replacement of insulation in the reactor building. When the plant restarts after maintenance the temperature rises and the insulation in the reactor building undergoes some thermal decomposition. It produces steam containing formaldehyde within the containment in the reactor building, and this in turn may produce carbon monoxide.

5 : SUMMARY OF ENVIRONMENTAL AND PAGE : 5 / 10 Ammonia will be produced during the restarting process as a result of the thermal degradation of hydrazine used for the wet conditioning of steam generators during unit shutdown. Ammonia at the Flamanville 3 plant is to be discharged via atmospheric valves located approximately 30 m above the platform floor. Modelling to assess the dispersion of the ammonia indicated that on the basis of the short duration and quantity of ammonia to be discharged to atmosphere, potential environmental impacts are considered to be negligible. Potentially odorous emissions resulting from the operational phase of the installation have been identified in the Flamanville 3 assessment, as formaldehyde and ammonia discharges by the EPR unit and exhaust fumes. As with odours generated during the construction phase, quantities released will be small and will be rapidly dispersed such that they should not result in a noticeable odour beyond the site boundary. Potential impacts on microclimate are site specific but may include: Changes to the airflow around new large buildings and structures and wind turbulence; Addition of moisture leading to increased fog and potentially icing; Reduced sunlight; and Ponding of cold air behind physical barriers. The potential impacts on air quality of a UK installation will to a large extent depend on the site location, existing air quality in the locality, the proximity of sensitive receptors, local topography and meteorology which will influence the dispersion of emissions. However, on the basis of the Flamanville 3 assessment and following the implementation of the suggested mitigation measures the impact of the installation on local air quality should be low to negligible. 6. NOISE 6.1. CONSTRUCTION Possible sources of noise during the construction include: The use of excavator mounted and/or hand held pneumatic breaking equipment, excavators and dump trucks. Blasting if excavations are to be undertaken within the bedrock. Foundation excavation to be undertaken by 360 excavators with spoil being removed by dump trucks. In the event of foundations requiring dewatering, generators and submersible pumps may be utilised on site. Material generated onsite (by blasting/foundation excavation and general earthmoving) may require crushing/grading before it can be reused on the site as fill material or aggregate for concrete production. This will require the operation of crushers and/or grading plant and associated onsite haulage.

6 : SUMMARY OF ENVIRONMENTAL AND PAGE : 6 / 10 The adoption of a Construction Management Plan and operation in accordance to best practice during the construction phase should minimise noise disturbance to nearby noisesensitive receptors as far as reasonably practicable. However, it is recognised that due to the nature of construction works, there is still the potential for a temporary adverse impact at nearby noisesensitive receptors. However, this is considered to be of minor magnitude OPERATION Nuclear power plants are sources of constant noise (linked to the operation of transformers, turbine generator units, ventilation systems, pumps, etc.) and intermittent noise (the use of emergency diesel generators, etc.). Site specific factors such as building design and layout will be controlling factors in noise levels created by the development as much of the (noise producing) machinery will be contained within the building structures. Given the nature of the development, it is likely that the buildings themselves will offer significant noise attenuation. As a result, there is the potential for noise sources external to the building, such as the movements of vehicles on and offsite, to pose the greatest risk of impact to nearby noisesensitive receptors. The operation of the EPR should have a negligible impact on nearby noisesensitive receptors. However, in the unlikely event that noise complaints are received, a comprehensive complaints procedure should be established at the site. 7. LANDSCAPE 7.1. CONSTRUCTION For the UK EPR, the clearance of the site will inevitably have an impact on existing landscape features and habitat. This could range from impacts on geological features associated with coastal cliffs and beaches to removal of grassland habitat, trees and natural shrub vegetation. Impacts could also apply to agricultural land and hedgerows. The construction works themselves may be more visible from the surrounding area in the short term than the finished development. Tower cranes will be used to lift and position elements of the buildings into place and this has implications for views from the surrounding area. The construction process at Flamanville will involve the manufacture of concrete elements on the site from raw materials with these then being fitted directly into place. If this occurs at a UK site, a substantial amount of construction plant could be involved and is likely to be clearly visible from the seaward side for a coastal location OPERATION The UK EPR development may have the potential to impact on the pattern of the coastal landscape, particularly when viewed from the sea and the materials and colours adopted will be important in terms of harmonizing with the wider setting.

7 : SUMMARY OF ENVIRONMENTAL AND PAGE : 7 / 10 Significant areas of the UK coastline are designated as heritage coastline, particularly within the south east of England and along the north east coast. Historic buildings and fortifications are an important cultural asset and are often associated with tourism. The setting of the coastline and the cultural heritage must be considered for the site of an UK EPR. There is a potential for night time visual impacts from the lighting associated with the development. 8. HUMAN HEALTH 8.1. CONSTRUCTION At Flamanville, there is no potable groundwater at risk of pollution from the construction of the EPR, therefore assessment of the health impacts of nonradiological discharges into the groundwater was not carried out. However, groundwater may be present beneath a UK site therefore an assessment of the health impacts of discharges into groundwater will be required. The potential for impacts on human health relating to the generation and deposition of dust during the construction phase will depend on the site location and the proximity of sensitive receptors. However, on the basis that measures will be implemented to reduce the potential for the production of dust, significant impacts on human health would not be anticipated from such activities. The potential for impacts on human health relating to transportation during the construction phase will depend on the number and type of deliveries, transport mode and the proximity of sensitive receptors. However, on the basis that mitigation measures will be implemented, significant impacts on human health would not be anticipated from such activities. For test phase at Flamanville 3, a range of substances were assessed and compared with mandatory standards. The assessments concluded that the substances released during the test phase were in accordance with those modelled for the operational phase. The modelled releases for the operational phase were deemed to have no impact upon human health, therefore, the test phase releases were also deemed to have no impact upon human health OPERATION The following substances at the Flamanville site were identified as potentially toxic and occurring at concentrations requiring a quantitative assessment: iron, copper, aluminium, bromoform, hydrazine, nitrates, morpholine and ethanolamine. These substances may impact human health in various ways such as weight loss, neurological, liver, kidney, haematological and digestive disorders. For Flamanville 3 a detailed quantitative assessment demonstrated that: Direct exposure to iron and bromoform posed no risk of toxic effects; The levels of hydrazine, nitrates, morpholine and ethanolamine were below mandatory standards and exposure limits;

8 : SUMMARY OF ENVIRONMENTAL AND PAGE : 8 / 10 Indirect exposure to copper, through ingestion via local seafood posed no risk of toxic effects. Potential effects on air quality during the operational phase of the EPR could result from: Exhaust emissions associated vehicles delivering materials to site, the removal of waste and the transportation of employees to the site; and Process related emissions including exhaust emissions from the use of backup generators, formaldehyde and CO emissions from unit maintenance operations, and ammonia from equipment restarting after shut down. Assessment of impacts upon human health at Flamanville 3 concluded that there is no significant impact upon human health. 9. RADIOLOGICAL There are not expected to be any significant radiological impacts from the construction of the EPR. Small impacts due to naturally occurring radioactive materials would be bounded by the nonradiological impacts. The following sections are therefore confined to radiological and environmental impacts from operation of the plant REACTOR FUEL IMPACTS AT THE FRONT AND BACK ENDS OF THE FUEL CYCLE The EPR incorporates a range of design features that provide positive benefits in terms of the impacts on use of resources at the front end of the fuel cycle and the impacts of waste arisings at the end of the fuel cycle. The design features centre on: Increased fuel burn up Longer fuel cycles Reactor core design and fuel loading that provide improved neutron economy. Some self burning of plutonium in the fuel. Improved primary to secondary circuit heat transfer systems. With respect to impacts at the front end of the fuel cycle (mining and refining uranium) these design and operational features of the EPR design are expected to provide savings in the use of natural uranium of 17% over and above those of current PWR reactor designs for the same electrical output. With respect to the back end of the fuel cycle, discharged fuel (assuming standard UO 2 ) should contain less plutonium and, in the event of reprocessing, give rise to less fuel cladding and fission products per unit energy produced compared with current French 1,300 MWe plants.

9 : SUMMARY OF ENVIRONMENTAL AND PAGE : 9 / OPERATIONAL LIQUID, GASEOUS AND SOLID RADIOACTIVE WASTES. Like any power plant or PWR, the EPR will produce a range of liquid, gaseous and solid radioactive wastes. The design and operation of the plant will draw on 20 years experience to ensure these are minimised at source and those that do arise are treated in accordance with best practice, taking account of worker doses, costs and environmental impacts. In summary, the design and operational features are expected to minimise the impacts relative to those of current 1,300 MWe PWR plant. Main impacts are as follows: Discharges of liquids containing radionuclides in the groups of tritium, carbon 14, iodine isotopes and, in smaller amounts, fission and activation products. The EPR incorporates a range of design features to minimise these at source and ensure abatement prior to discharge. In summary, the amounts expected on design bases, with a comparison to current PWR plant are summarised as follows: Category of radionuclides Expected activity discharged by EPR (in GBq/year) Carbon14 23 ~0 Tritium ~0 Iodines Comparison of specific activity 1 compared to a typical existing 1300 MWe unit (%) Other fission or activation products Table E.9a: amounts of liquid discharges by EPR expected and comparison with equivalent PWR plant Discharges of gases containing radionuclides in the groups of tritium, carbon 14, iodine isotopes, noble gases and smaller amounts of other fission or activation products. The EPR incorporates a range of design features to minimise these at source and ensure abatement prior to discharge. In summary, the amounts expected on design bases, with a comparison to current PWR plant are summarised as follows: Category of radionuclides Expected activity discharged by EPR (in GBq/year) 2 Carbon Tritium Noble gases 800 ~0 Iodines Comparison of specific activity 3 compared to a typical existing 1300 MWe unit (%) Other fission or activation products ~0 Table E.9b: amounts of gaseous discharges by EPR expected and comparison with equivalent PWR plant 1 Activity per unit of produced energy. 2 Radioactivity measurement unit is the becquerel (Bq): 1 GBq = 1 billion Bq. To give a comparison, human being contains naturally Bq 3 Activity per unit of produced energy.

10 : SUMMARY OF ENVIRONMENTAL AND PAGE : 10 / HUMAN AND ENVIRONMENTAL IMPACTS OF RADIOACTIVE DISCHARGES. Design and operational features of the EPR minimise initial formation of radioactive waste at source and then use BPEO and BPM for abatement of those radioactive wastes that do arise, drawing on best available practice and experience. Under careful control and in accordance with authorisations, there is a need to discharge low levels of gaseous and liquid radioactive waste. Impacts of these would need to take account of sitespecific factors and habit surveys in accordance with current UK Regulatory requirements. An analogous exercise for a planned EPR at a coastal site at Flamanville in France, where two PWRs already operate, suggests the following net impacts: Public doses: All calculated total doses to the most exposed groups are at least two orders of magnitude lower than the 1 msv public dose limit that applies in both France and the UK and lower than the average dose from all sources of natural radiation in France of 2.4 msv/year (fluctuations from one area to another may double this value). The dosimetric impact of the EPR unit and of the two existing units at the Flamanville site is therefore far below the dose from exposure to natural radioactivity in the area. Given a natural background in the UK of ~2 msv/year, a similar situation is likely to pertain to any UK site chosen for an EPR (and would be substantiated by similar site specific assessments). Marine impacts: The liquid radioactive waste discharged into the English Channel by the EPR unit will mix with the same waste produced by the Flamanville site's units 1 and 2 as well as the spent fuel reprocessing plant waste from La Hague. Surveys suggest that it is unlikely to be readily possible to distinguish or differentiate between the various potential historic or current or new sources of nuclides in the Flamanville environment once the EPR is operative. The specific activity of the radionuclides which are artificially produced by the nuclear plants on the Atlantic coast will remain low in comparison to the environmental samples' natural radioactive component. Terrestrial impacts for the site area: The very low nonradioactive gaseous discharges are not expected to have any detectable impact on air quality (for radiological parameters) and the operating of the EPR unit will not significantly modify the Flamanville site's current radio ecological conditions. Radioactive waste will be treated and stored in a building connected to the BAN, which will ensure that the packages will not leave the controlled area (thus minimising impacts of package drops). Only final packaged radioactive waste, meeting the NII principals of containment, passive safety etc will leave the site by road or rail and would comply with all relevant UK requirements for transport of radioactive materials by road or rail DISCHARGES AND MONITORING. The EPR incorporates a range of features to ensure that all discharges are in accordance with the authorisations and can be recorded. Activities and volumes are measured prior to discharge and during discharge. This is supported by a site specific environmental monitoring programme that is initiated in advance of plant operation (to provide a baseline) and continues through all phases of operation and decommissioning.