Activity concentration of 137Cs and natural radionuclides in soil around the Belarusian nuclear power plant in the pre-commissioning period

Abstract In this study, soil cores (0–20 cm) were collected at 45 sites located within a 30-km radius zone around the Belarusian nuclear power plant (BelNPP) in 2019 before its commissioning. Activity of gamma-emitting radionuclides was measured in the samples using HPGe detectors. The study revealed low levels of 137Cs in the soil: the weighted average dry weight (d.w.) activity concentration (ACw) varied from 1.13 to 8.71 Bq/kg (d.w.). The ACw of natural radionuclides ranged: for 226Ra from 7.8 to 30.8 Bq/kg (d.w.), for 232Th from 10.9 to 33.0 Bq/kg (d.w.), and for 40K from 376 to 789 Bq/kg (d.w.). A good agreement between the ambient dose equivalent rate (ADER) values calculated with the soil samples and the ADER values previously measured in situ at the same sites is observed. The sites characterized here now have established pre-operational levels of 137Cs, 226Ra, 232Th, and 40K in soil thus can be surveyed again in future environmental studies.