Natural Radionuclides in Soils of Natural-Technogenic Landscapes in the Impact Zone of Potassium Salt Mining

This study considers the contents of natural radionuclides (Ra-226, Th-232, and K-40) in the soils of natural-technogenic landscapes in the Verkhnekamskoe potassium-magnesium salt deposit (Perm Krai, Russia). The purpose of the study is to assess the lateral activity distribution of natural radionuclides (Ra-226, Th-232, and K-40) in the soils of natural-technogenic landscapes of the mining areas on the territory of the Berezniki-Solikamsk industrial hub. Seventy-five soil samples from depths of 0-0.4 m are examined. The specific activities of the natural radionuclides Ra-226, Th-232, and K-40 in the soil samples are measured using gamma spectrometry. The average values of the activity concentrations of Ra-226, Th-232, and K-40 are 11.78 Bq/kg, 8.11 Bq/kg, and 246.9 Bq/kg, respectively. A gamma survey is conducted using the MKS/SRP-08A search dosimeter-radiometer over a control point framework covering 50,000 hectares. The research shows that the migration of the studied natural radionuclides is limited to a radius of 10 km. The results of the gamma-radiation measurements in the study area fall within a range of 0.06-0.25 mu Sv/h, which does not exceed the permissible limits. According to the findings, there is an increase in the concentration of natural radionuclides in transit supra-floodplain terrace landscapes and accumulative floodplain landscapes in the area affected by potash mining.