Studies on natural and fallout radioactivity mapping of the proposed Mithivirdi Atomic Power Project Site in Bhavnagar District, Gujarat, India

Abstract

The activity and gamma-absorbed dose rate due to the naturally occurring (226Ra, 232Th, and 40K) and anthropogenic (137Cs) radionuclides in the terrestrial environment were determined in soil samples collected around Mithivirdi Atomic Power Project Site, Bhavnagar District, Gujarat, by using gamma-ray spectrometry. The mean concentration levels measured in soil from the naturally occurring radioisotopes 226Ra, 232Th, and 40K are lower than the corresponding global average values reported worldwide. 137Cs activity in the soil sample is comparable with the preoperational baseline level activity of other nuclear power plant sites in India. The total outdoor effective dose rates due to soil ranged 16.7–79.5 μSv/y with the median value of 34.3 μSv/y. The absorbed dose rate due to cosmic components around Mithivirdi site was found to be in the range of 44.4–90.6 nGy/h.

Keywords

• cosmic
• gamma dose rate
• mithivirdi
• natural radioactivity