MARINE ENVIRONMENTAL-RADIOACTIVITY - THE MISSING SCIENCE

In paying attention to the specific needs of radiological protection a nd the protection of man and the environment from ionizing radiation, insufficient attention has been paid to the identification of prime pr ocesses which control the distributions of radionuclides, A major omis sion has been a failure to optimize the use of cost effective direct o bservational data for the in situ distribution of radionuclides in sed iments by autoradiographic techniques, Here I consider the distributio n of alpha particle radioactivity, together with some actinides in mar ine/estuarine sediments of the Cumbrian coast, England. Today, the alp ha particle radioactivity from Pu, Am and Cm, originating from authori zed low level discharges of effluents into the NE Irish Sea from the B ritish Nuclear Fuels pie plant at Sellafield, is associated with three main phases: BNFL hot particles, the minerals haematite and magnetite and hydrated iron oxide flecks which are associated with quartz grain s. The receiving environment contains large quantities of industrial i ron together with other elements, from haematite mining, blast furnace production of iron, coal mining and phosphogypsum wastes. These waste s have interacted with the radionuclides, but as the industrial activi ties have now ceased, future distributions of alpha emitters are likel y to be different and existing transport-dispersion models may not be suitable. Preliminary evidence indicates that the rate of loss of stab le and radioactive elements from coastal waters may have increased. Th is applies to most of the UK coastal waters. In order to understand th e behaviour of radionuclides in marine and estuarine systems, site spe cific characteristics must be recognized. The use of global values and vague operational concepts in order to account for radionuclide distr ibutions has limited scientific meaning. (C) 1998 Elsevier Science Ltd . All rights reserved.