Spatial Distribution of Natural and Artificial Radionuclides in Urban Soils and Bottom Sediments of Monchegorsk Lakes: Russia

The article presents the results of a study of soils and bottom sediments of lakes in the area of Monchegorsk city. The purpose of the work is to identify patterns of distribution of natural and man-made radionuclides in urban soils and bottom sediments of lakes in Monchegorsk city. The specific activity values of radionuclides in urban soil samples were as follows: for technogenic Cs-137, up to 31.3 Bq/kg; in soils in the zone of influence of the plant (in subflare areas), up to 63.4 Bq/kg. For natural radionuclides in urban soils, the values were as follows: Ra-226 - up to 14.2 Bq/kg; in soils in the zone of influence of the plant (in sub-flare areas) - up to 21.6 Bq/kg; Th-232 in urban soils - up to 1. The concentration of 8.3 Bq/kg was observed in soils in the zone of influence of the plant (in sub-flare areas), while the concentration of 17 Bq/kg was observed in soils in the same area. The concentration of 498 Bq/kg was observed in urban soils for K-40, while the concentration of 317 Bq/kg was observed in sub-flare areas. In bottom sediments of lakes, the concentration of technogenic Cs-137 was found to be up to 45.8 Bq/kg, while the concentration of natural radionuclides, including Ra-226 (up to 62.6 Bq/kg), Th-232 (11 Bq/kg), and K-40 (268 Bq/ kg), was also determined.