A COMPARATIVE-STUDY OF THE SPECIATION AND BEHAVIOR OF PLUTONIUM IN THE MARINE-ENVIRONMENT OF 2 REPROCESSING PLANTS

New data are presented which highlight to the behaviour of Pu upon dis charge into the open sea from nuclear reprocessing plants at Sellafiel d and Cap La Hague and Sellafield. Specifically, certain physico-chemi cal characteristics of Pu in sea water and sea-bed sediments are shown to be independent of both the source and near-field environmental con ditions. For example, in filtered sea water the discharge-normalized P u concentrations are similar at both sites (ca. 20-40 mu Bq l(-1) per GBq discharged). The oxidation state distribution of Pa is also simila r, with Pu(V,VI) predominating. A significant fraction of the Pu(III,I V) present in filtered water is associated with > 1 kDa colloids. In e ach zone, tide energy would appear to control the long-range dispersio n of Pu in both the filtered and particulate fractions.