Sea to land transfer of anthropogenic radionuclides to the North Wales coast, Part II: Aerial modelling and radiological assessment

Modelling calculations have been performed to predict the radiological impact of the sea to land transfer pathway to members of the public in North Wales from 1952 to 2004. The radionuclides of interest were 99Tc, 137Cs, 239,240Pu and 241Am and the exposure routes considered were food consumption, external and inhalation. The consumption of locally grown terrestrial food in the early to mid 1980s was the most significant source of exposure to all of the groups considered, with 239,240Pu being the radionuclide contributing most to the dose. A maximum dose of 1.46 μSv y−1 was calculated for adult members of the critical consumption group in 1985, with doses for 2004 reducing to 0.59 μSv y−1. Despite the conservative approach of the dose calculations, the dose rate values are very low, less than 0.15% of the annual limit of 1000 μSv y−1 for the UK public from controlled radiation sources (excluding medical).