Radiometric investigations of Kara Sea sediments and preliminary radiological assessment related to dumping of radioactive wastes in the Arctic Seas

Abstract

There has been world-wide concern over the possible health and environmental impacts of the dumping of radioactive wastes in shallow waters of the Kara and Barents Seas. During 1992, IAEA-MEL participated in a joint Russian-Norwegian expedition to the region and collected a suite of sediment cores for characterization of downcore radioactivity distribution patterns and inventories with the aim of assessing past and present inputs of radionuclides. The 137Cs, 238Pu, 239,240Pu, and 241Am contents of the 0–1 cm sections range from 17 to 32, 0·01 to 0·06, 0·4 to 1·3 and 0·2 to 0·5 Bq kg−1 (dry wt), respectively. The 238Pu/239,240Pu and 241Am/239,240Pu activity ratios are consistent with those reported for global fallout. Detailed information on downcore radionuclide distribution patterns and inventories, as well as an account of sedimentation parameters, are presented.A preliminary assessment of the long-term radiological impact of radioactive waste disosal in the Arctic Seas, on global and regional scales, has been made. The modelling results suggest that the global radiological impact of the disposals will be comparable to or less than those resulting from other anthropogenic and natural sources of radioactivity. However, radiological effects on the regional scale may be of importance.IAEA is carrying out a 4 year International Arctic Seas Assessment Project (IASAP) that will comprehensively cover all aspects of radioactive dumping in the Arctic Seas and it will be reported to the London Convention in 1996. The IAEA-MEL study described here represents a preliminary contribution to IASAP.