Cefas contract report C2848 Radiological Habits Survey: Aldermaston and Burghfield, 2011 2012 Environment Report RL 03/12 This page has been intentionally left blank Environment Report RL 03/12 Final report Radiological Habits Survey: Aldermaston and Burghfield, 2011 V.E. Ly, C.J. Garrod, F.J. Clyne and P. Rumney Peer reviewed by G.J. Hunt Approved for publication by W.C. Camplin 2012 The work described in this report was carried out under contract to the Environment Agency, the Food Standards Agency and the Health and Safety Executive. Cefas contract C2848 FSA Project PAU 198 / Lot 7 / ERI006 This report should be cited as: Ly, V.E., Garrod, C.J., Clyne, F.J. and Rumney, P., 2012. Radiological Habits Survey: Aldermaston and Burghfield, 2011. RL 03/12. Cefas, Lowestoft A copy can be obtained by downloading from the Cefas website: www.cefas.defra.gov.uk © Crown copyright, 2012 2 Radiological Habits Survey: Aldermaston and Burghfield, 2011 CONTENTS SUMMARY .............................................................................................................................................. 7 1 INTRODUCTION ........................................................................................................................... 12 1.1 Regulatory framework ........................................................................................................... 12 1.2 Radiological protection framework ........................................................................................ 13 2 THE SURVEY ............................................................................................................................... 15 2.1 Site activity ............................................................................................................................ 15 2.2 Survey objectives .................................................................................................................. 15 2.3 Survey areas ......................................................................................................................... 16 Figure 1. The Aldermaston aquatic survey area ........................................................................... 18 Figure 2. The Aldermaston and Burghfield terrestrial survey areas ............................................. 19 Figure 3. The Aldermaston direct radiation survey area............................................................... 20 Figure 4. The Burghfield direct radiation survey area ................................................................... 21 2.4 Conduct of the survey ........................................................................................................... 22 3 METHODS FOR DATA ANALYSIS ............................................................................................. 25 3.1 Data recording and presentation ........................................................................................... 25 3.2 Data conversion .................................................................................................................... 25 3.3 Rounding and grouping of data ............................................................................................. 26 3.4 Approaches for the identification of high rates ...................................................................... 27 3.5 Data quality ........................................................................................................................... 28 4 AQUATIC RADIATION PATHWAYS ........................................................................................... 30 4.1 Aquatic survey area .............................................................................................................. 30 Figure 5. Aldermaston Park Lake ................................................................................................. 31 Figure 6. Aldermaston Stream ...................................................................................................... 32 Figure 7. River Kennet .................................................................................................................. 33 Figure 8. Kennet and Avon Canal................................................................................................. 34 Figure 9. Silchester Brook ............................................................................................................ 35 4.2 Commercial fisheries ............................................................................................................. 35 4.3 Angling .................................................................................................................................. 35 4.4 Sewage Treatment Works ..................................................................................................... 36 4.5 Other pathways ..................................................................................................................... 36 4.6 Food consumption data ......................................................................................................... 36 4.7 Bankside occupancy ............................................................................................................. 36 Table A. Summary of adults’ bankside occupancy rates .............................................................. 37 Table B. Summary of children’s bankside occupancy rates ......................................................... 37 4.8 Gamma dose rate measurements......................................................................................... 38 4.9 Handling of fishing gear ........................................................................................................ 38 Table C. Summary of adults’ handling rates of fishing gear ......................................................... 39 4.10 Exposure to sewage sludge .................................................................................................. 39 4.11 Water based activities ........................................................................................................... 39 5 TERRESTRIAL RADIATION PATHWAYS .................................................................................. 41 5.1 Terrestrial survey areas ........................................................................................................ 41 5.2 Destination of food originating from the terrestrial survey areas .......................................... 43 5.3 The transfer of contamination off-site by wildlife ................................................................... 44 5.4 Food consumption data ......................................................................................................... 44 Table D. Summary of adults’ consumption rates of foods from the terrestrial survey areas ......... 45 Table E. Summary of children’s and infants’ consumption rates of foods from the terrestrial survey areas .................................................................................................................................. 46 6 DIRECT RADIATION PATHWAYS .............................................................................................. 47 6.1 Direct radiation survey areas ................................................................................................ 47 6.2 Residential activities .............................................................................................................. 48 3 CONTENTS 6.3 Leisure activities .................................................................................................................... 49 6.4 Commercial activities ............................................................................................................ 49 6.5 Educational activities ............................................................................................................. 50 6.6 Occupancy rates ................................................................................................................... 50 Table F. Summary of occupancy rates (h y -1) in the Aldermaston and Burghfield direct radiation survey areas .................................................................................................................................. 50 6.7 Gamma dose rate measurements......................................................................................... 52 7 USES OF HABITS DATA FOR DOSE ASSESSMENTS ............................................................. 53 7.1 Combined pathways .............................................................................................................. 53 7.2 Foetal dose assessment ....................................................................................................... 53 7.3 Total dose assessment ......................................................................................................... 54 8 COMPARISONS WITH THE PREVIOUS SURVEY ..................................................................... 55 8.1 Aquatic survey area .............................................................................................................. 55 Table G. Comparison between 2002 and 2011 consumption rates of aquatic food groups for adults ............................................................................................................................................. 55 Table H. Comparison between 2002 and 2011 bankside occupancy rates and handling rates of fishing gear for adults