RADIOGEOCHEMICAL INVESTIGATIONS OF 2002 IN SHALLOW BAYS OF THE NOVAYA ZEMLYA ARCHIPELAGO

Abstract

The paper presents the results of a survey of underwater disposal sites of potentially hazardous objects in the Kara Sea and Stepovogo Bay. The real levels of radioactivity were determined in the near and remote zones of the submerged solid radioactive waste studied in the outer and inner parts of the Stepovogo Bay. No increase in the level of radioactivity was detected in the region where a nuclear submarine (NS factory no. 601) was submerged, which suggests the tightness of the safety barriers of the submerged object. In the center of the inner part of the bay, at the repository of containers with solid radioactive waste, local areas of bottom sediment contamination were documented directly near the object. Presently, they exert no considerable ecological loading on the water region. At the expense of exchange processes in the bottom-water system, part of the activity is transported into the water, which results in an increase in the activity of particular radionuclides in the deep layers of the water body. The geochemical characteristics of the upper layer of bottom sediments indicate the possible occurrence of active corrosion processes in the inner part of the bay, which, together with the X-ray fluorescence data on the presence of corrosion elements in bottom sediments, calls for an investigation of corrosion processes in the buried object-marine environment system. The hydrologic conditions in the inner part of the bay, namely the occurrence of two water layers with different hydrophysical characteristics, prevent deep water exchange between various parts of the bay, which results in the localization of contaminated deep waters in the inner part of the bay. The results obtained for radionuclide activity (primarily cesium-137) in the surface waters suggest that there is no radionuclide input into the Stepovogo Bay with river runoff from the Novaya Zemlya Archipelago.