Assessment of naturally occurring radionuclides around England and Wales: Application of the G-BASE dataset to estimate doses to non-human species

¹ British Geological Survey (BGS), Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK
² Centre for Ecology & Hydrology, CEH-Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
³ Radioecology Unit, SWIMMER, University of Liverpool, The Nicholson Building, Liverpool L69 3GP, UK
⁴ Environment Agency, PO Box 12, Richard Fairclough House, Knutsford Road, Warrington WA4 1HG, UK

Abstract

An assessment of the natural radiation dose to wildlife in England and Wales was made to determine the contribution it may make to the total radiation dose estimated during environmental impact assessments. Significant use was made of systematic datasets for environmental media (stream sediments, stream waters and soils), in particular those produced by the Geochemical Baseline Survey of the Environment (G-BASE) project. This provided extensive, although variable, coverage for different elements and sample types after normalisation of data to account for changes in sampling and analysis over time. Almost complete coverage for K in stream sediments was achieved by merging G-BASE and Wolfson Atlas data. This required normalisation of the Wolfson data to the G-BASE results. Coverage was improved greatly for U and Th in sediments, and K, U and Th in soils, by using the strong relationship between soils and sediments and geology (both solid and superficial) to extrapolate the data. The total U, Th and K data were used to derive activity concentrations of ²³⁸U and ²³²Th series radionuclides and ⁴⁰K. External dose rates to wildlife were then estimated from derived media concentrations; internal dose rates were estimated from measured activities in biota or activities predicted using recommended concentration ratios.