Fallout 137Cs, 90Sr and 239+240Pu in soils polluted by heavy metals:: Vertical distribution, residence half-times, and external gamma-dose rates

The industrial pollution of an ecosystem, e.g., by heavy metals, might also affect the behavior of fallout radionuclides in the soils of these areas. To study such effects, we determined at various distances from the huge copper-nickel smelters at Monchegorsk on the Kola Peninsula Russia) and at a reference site: (1) the vertical distribution of fallout Cs-137, Sr-90 and Pu239+240 in the soil, (2) the corresponding residence half-times in different soil horizons, and (3) the resulting external gamma-dose rates at these sites in 1 m height due to Cs-137 in the soil. The data show that the residence half-times and the partitioning of the fallout radionuclides among the various soil horizons depend significantly on the extent of the heavy metal pollution at the sites. The resulting external gamma-dose rate in 1 m height due to Cs-137 in the soil is, however, rather similar at the various sites.