Ambient dose equivalent rates of gamma radiation from natural radionuclides and 137Cs at grasslands and forests in the area of the Belarusian NPP in the pre-commissioning period (2019)

Abstract

Abstract In situ gamma-spectrometric measurements were performed at grasslands (45 plots) and forests (6 plots) in the vicinity of the Belarusian nuclear power plant in September–October 2019. The aim of the study was to evaluate the baseline level of ambient dose equivalent rates of gamma radiation from natural radionuclides and 137Cs in the period preceding the commissioning of the NPP. The study revealed more than a 2-fold variability in values of the total ambient dose equivalent rate: from 29 to 72 nSv/h. This spread can be explained by variability in the content of natural radionuclides in the environment and, accordingly, ambient dose equivalent rate. At forest sites, compared to grassland sites, the values of ambient dose equivalent rates of gamma radiation from natural radionuclides were statistically significantly lower. The contribution of gamma radiation from 137Cs to the total ambient dose equivalent rate was insignificant and averaged 3% for grasslands and 6% for forests.