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Temporal changes in gamma dose rates in the Esk Estuary, UK

Published online by Cambridge University Press:  09 January 2012

M.D. Wood
Affiliation:
School of Science & the Environment, Manchester Metropolitan University, Manchester, M1 5GD, UK
D. Copplestone
Affiliation:
School of Biological & Environmental Sciences, University of Stirling, Stirling, FK9 4LA, UK
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Abstract

Over the last 30 years there has been a reduction in the radioactive discharges from the UK’s Sellafield site. Radionuclide activity concentrations in the environment around Sellafield have declined as a result. However, routine monitoring results from the nearby Esk Estuary show a less clear trend, with fluctuations in gamma dose rate measurements being reported from year to year. A comprehensive survey (n = 576) of gamma dose rates in the Esk Estuary was undertaken in 2007 and the data compared to a similar survey carried out in 1989. There was a highly statistically significant decrease in the external gamma dose rates within the Esk Estuary between 1989 and 2007. The measured total gamma dose rate range in 2007 was 0.064 – 0.235 μGy h−1with a mean of 0.123 μGy h−1. This equates to a maximum exposure of 0.200 μSv h−1. There was no evidence of large-scale sediment redistribution under current conditions. However, there was limited evidence to suggest that part of the reason for the reduction in measured dose rates was the burial of contaminated sediment deposits by uncontaminated sediments transported by tidal processes.

Type
Research Article
Copyright
© Owned by the authors, published by EDP Sciences, 2011

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References

RIFE 1996 - 2008. Radioactivity in Food in the Environment (RIFE-1 – RIFE 13). Available from: http://www.cefas.co.uk/publications/scientific-series/radioactivity-in-food- and-the-environment(rife).aspx
Emptage, M., Kelly, M. Gamma dose rates in the Esk Estuary. (University of Lancaster, Lancaster, 1990).
Kelly, M., Emptage, M. Distribution of radioactivity in the Esk estuary and its relationship to sedimentary processes. (University of Lancaster, Lancaster, 1991).
HMIP, Routine measurement of gamma ray air kerma rate in the environment – Technical Guidance Note (Monitoring) M5. (Her Majesty’s Inspectorate of Pollution, London, 1995).
Tyler, A.N., Sanderson, D.C.W., Scott, E.M., Allyson, J.D., J Environ Radioact 33 (1996) 213-235.
Thompson, I.M.G., Botter-Jensen, L., Deme, S., Pernicka, F., Saez-Vergara, J.C., Technical recommendations on measurements of external environmental gamma radiation doses – Radiation Protection 106 (European Commission, Luxembourg, 1999).
Ambrosi, P., Metrologia 46 (2009) S99-S111.
Wood MD, Hall PJ, Wittrick S, Copplestone D, Leah RT, Survey of gamma dose rates in air around the Esk Estuary (Environment Agency, Bristol, 2011)
ICRP, Ann ICRP 26 (1996).
Doddington, T., Camplin, W.C., Caldwell, P., Investigation of external radiation exposure pathways in the Eastern Irish Sea, 1989. (Ministry of Agriculture, Fisheries and Food (MAFF), Lowerstoft, 1990).