ENVIRONMENTAL RADIATION PROTECTION IN THE UNITED KINGDOM. The Environment Agency s approach. Clive Williams

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1 ENVIRONMENTAL RADIATION PROTECTION IN THE UNITED KINGDOM The Environment Agency s approach Clive Williams

2 Outline Introduction Context Tiered assessment approach The way forward 2

3 Introduction Environment Agency - principal environmental regulator in England and Wales Similar agencies for Scotland, Northern Ireland Authorisation of radioactive waste disposals/discharges from: 20 nuclear sites About 900 other users of radioactive substances 3

4 Context (1) - Legislation Need for environmental radiation protection is driven by existing conservation legislation Includes effects of radioactive substances Not (primarily) radiation protection legislation Not perceived or actual radiological hazard International legislation and obligations EU Habitats and Birds Directives OSPAR - Radioactive Substances Strategy Domestic UK legislation Environment Act 1995; Radioactive Substances Act 1993; Conservation (Natural Habitats) Regs

5 Context (2) Existing obligations have prompted UK developments Questions need to be addressed using sound science Need a system to assure the protection of plants and animals from the harmful effects of radiation Environment Agency has taken a lead in this field: R&D on assessment methodology, commissioned jointly by Environment Agency and English Nature Euratom FP5 Project FASSET Euratom FP6 Project ERICA R&D on effects of radiation on animals and plants Continuing links with ICRP, IAEA and OECD-NEA 5

6 Tiered assessment approach 6

7 Purpose EU Habitats and Birds Directives / UK Conservation (Habitats) Regulations Our obligations are to review: Full range of existing environmental permits, in combination All requests for variations to existing permits, or new applications Ensure that no permitted activity results in an adverse effect, either directly or indirectly, on the integrity of identified European Sites (Natura 2000 Sites) 7

8 Assessment Overview Stage 1 Natura 2000 sites which might be affected by authorised releases of radioactive substances identified using simple rules e.g. authorised aerial discharges within 1km Humber Estuary Stage 2: interim methodology produced in

9 Scientific basis of our assessment approach Environment Agency R&D Publication 128 Uses concept of reference organism - similar to EU FASSET and ERICA projects Enter water, air, soil or biota concentrations to calculate dose rates (µgy/h) Provides advice on practical use of methodology, and states assumptions and constraints Includes a range of radionuclides: 3 H, 14 C, 32 P, 35 S, 60 Co, 99 Tc, 90 Sr, 106 Ru, 125 I, 129 I, 131 I, 137 Cs, 210 Po, 226 Ra, 234 Th, 238 U, Pu, 241 Am, 85 Kr, 41 Ar Terrestrial, freshwater and coastal sites 9

10 Assessment Methodology RADIONUCLIDE SOURCE PATHWAY OF EXPOSURE ECOLOGICAL PARAMETERS REFERENCE ORGANISM Compare predicted dose to known biological or ecological effects & guideline values TOTAL ABSORBED DOSE IMPACT 10

11 Assessment Steps R&D 128 approach used by the Agency to produce a spreadsheet to review the maximum permissible radioactive discharge levels from authorised sites Doses calculated were compared with a conservative screening level (set at 5 µgyh -1 ) (Stage 2) Approximately 100 authorisations have been identified that exceed the screening level at 51 Natura 2000 sites Undertake detailed Stage 3 assessment - compare with 40 µgyh -1 assessment value 11

12 Determine authorisations affecting Natura 2000 site (from Stage 2) Obtain Natura 2000 site information Identify any predator/prey for indirect effects Having identified a feature species, determine concentration factors and occupancy factors Determine which reference organism geometry can be used to approximate the feature species geometry Run Assessment 12

13 9.E+01 8.E+01 7.E+01 6.E+01 5.E+01 4.E+01 3.E+01 2.E+01 1.E+01 0.E+00 Radionuclides: OBT, H-3, P-32, P-33, S-35, Co-60, Sr- 90, Tc-99m, Ru-106, I-125, I-129, I-131, Po-210 Other beta/gamma (t1/2 > 8 days) Other alpha Caesium-137 Carbon-14 Macrophyte Bacteria Zooplankton Small b. crust. Benthic mollusc Benthic fish Pelagic fish Large b. crust. Phytoplankton Fish egg Whale Seal Oystercatcher Seabird Dose rate µgyh -1 Snipe Lapwing Predicted Doses (Humber Estuary) 13

14 The way forward International developments - This Co-ordination Group In particular, the ICRP s recommendations Radiation effects experiments Targeted on ICRP Reference Animals and Plants Environmentally relevant dose rates Environment Agency is keen to collaborate Testing and validation Field-based measurements IAEA EMRAS Programme, Biota Dose Working Group EU ERICA Project case studies 14

15 Conclusion Recognised need for environmental radiation protection Staged and systematic assessment process in the UK Way forward - work towards an agreed international system 15