Background Radiation Dose to the Population Around the Kudankulam Nuclear Power Plant

In Kudankulam (a small village near Cape Comerin, the southernmost tip of the Indian subcontinent), two nuclear power reactors of 1000 MWe each are now under construction. To create baseline data regarding natural background radiation, systematic measurements of the radiation levels in soil, sand, air, and indoors have been performed. Five taluks situated in three different districts lying within a 30-km radius have been chosen as the study area for the present measurements. Primordial radionuclide concentration in sand and soil samples has been measured, and sparse distribution of monazite has been discovered in some places along the coastal areas of Kanyakumari district. The annual effective dose from the three primordial radionuclides in soil samples to the population living around the Kudankulam nuclear power plant is 0.149 mSv/year. The average annual effective dose from primordial radionuclides in sand samples is found to be 0.994 mSv/year. The annual effective dose from indoor gamma radiation has been calculated as 1.18 mSv/year. The effective dose rate from radon, thoron, and their progeny varied from 0.05 to 22.23 mSv/year, with a geometric mean value of 0.62 mSv/year. The overall dissolved radon concentration in drinking water samples was found to vary between background level (<26 mBq/1) and 9939 +/- 247 mBq/1.