Radiological assessment of the Belarusian nuclear power plant site in the pre-operational period

Field studies on the pre-operational period of a Belarusian NPP have allowed us to determine the “background” level of gamma-emitting radionuclides in individual components of the environment. The results of measuring the dose rate at the NPP construction site are from 0.048 to 0.089 μSv/h. External radiation in the surveyed area is at 96% due to 40K, ²²⁶Ra and 232Th. The radionuclides in the surface soil layer are: 40K - from 530 to 700 Bq/kg; ²²⁶Ra - from 30 to 55 Bq/kg; and 232Th - from 17 to 35 Bq/kg; 137Cs from 2 to 13 Bq/kg. The dose rate in the floodplain of the Viliya River from 0.033 to 0.082 μSv/h. The activity concentrations of the radionuclides in the surface soil layer of the floodplain of the Viliya River are: 40K - from 390 to 690 Bq/kg; ²²⁶Ra - from 33 to 50 Bq/kg; 232Th - from 15 to 50 Bq/kg; 137Cs - from 3 to 12 Bq/kg. The activity concentration of carbon-14 and tritium in the dominant vegetation species were determined to be: from 74.4 to 111.5 pMC and less than lower range limit, respectively.