Radioactive contamination of populated areas of the Krasnoyarsk krai in the region of location of the Mining-Chemical Combine

Radionuclide content in soil samples collected from populated areas of the Krasnoyarsk krai in the region of location of the Mining-Chemical Combine ( MCC), RF Ministry of Nuclear Power Engineering (Minatom), Zheleznogorsk, is determined. The samples were analyzed in the State Sanitary Epidemiologica l Inspection Center of the Krasnoyarsk krai (Krasnoyarsk, Russia) and analy tical and Radiochemical Laboratory (Spiez, Switzerland). In the soil sample s collected from the areas that are not subject to the impact of MCC (due t o contaminated water discharge and airborne effluents) the maximal content of the most radiologically significant technogenic radionuclide Cs-137 was found to be 45 Bq/kg, which does not exceed the global level: In flood land it amounts to 631 Bq/kg, and the absolutely maximal content (6507 Bq/kg) w as found in the samples collected at a depth of 50-80 cm from the Gorodskoi Isl. near the Yeniseisk town. The Pu-239,Pu-240 content in top horizons of soil outside the MCC impact zone ranges from 0.2 to 0.6 Bq/kg. In the floo d areas of populated localities at the Yenisei River the Pu-239,Pu-240 cont ent increases to 3.2 Bq/kg in top horizons and more significantly in deeper horizons. The maximal Pu-239,Pu-240 content (8-10 and 10.6-28.9 Bq/kg dete rmined by the Russian and Swiss Researchers, respectively) is found in the samples collected from Yeniseisk at a depth of 50-80 cm. These results sugg est that Pu is supplied from MCC to the flood areas of populated localities with the river water. An increased Pu-239,Pu-240 content was also found in soil samples collected from the free-fall areas of the Atamanovo and Bol's hoi Balchug settlements located near the MCC sanitary zone.