Anthropogenic radionuclides in Peter the Great bay

A comprehensive investigation of radionuclide distributions in seawater and bottom sediments of Peter the Great bay was conducted in September-October 1994. Sampling sites were chosen close to potential radioactivity sources as well as in fishing and recreational areas. The results have shown that t he main sources of radionuclides in Peter the Great bay are still global at mospheric fallout and the discharge of freshwater and suspended sediments f rom river runoff. Activities of Cs-137 and Sr-90 in seawater were in the ra nges 1.7-5.7 and 1.7-6.6 Bq m(-3) respectively, with activities of Cs-137 i n bottom sediments <1.1-22.9 Bq kg(-1) (dry weight). As a result of the acc ident with a nuclear submarine reactor in 1985, Co-60 was found in bottom s ediments of Strelok bay (close to Chazhma bay entrance, up to 150 Bq kg(-1) ) and in a limited area in Ussuriysky bay (up to 21.6 Bq kg(-1)). Further s tudies in 1996 and 1997 also did not reveal any radionuclide sources connec ted with the navy facilities except for the consequences of the Chazhma bay accident. (C) 2000 Elsevier Science Ltd. All rights reserved.