11. Specific patterns of 137Cs, 60Co, and 54Mn accumulation by macrophytes and bottom sediments

The data of long-term radioecological investigations conducted in the cooling water basin (Lake Drūksiai) of the Ignalina Nuclear Power Plant (INPP) are overviewed. The levels of specific activity of artificial radionuclides (137Cs, 60Co, and 54Mn) in macrophytes and bottom sediments were identified in the samples collected from four monitoring stations in Lake Drūksiai, from the channel of industrial storm water discharge (ISW-1,2), and from the cooling water channel of the INPP. The activity levels of artificial radionuclides in the lake and in the channel ISW-1,2 in a three-year period before and two-year period after the shutdown of the INPP were compared. The effects of heated water and chemical substances disposed with radionuclides from the INPP into Lake Drūksiai on accumulation of radionuclides by macrophytes before the shutdown of the INPP were evaluated.