222Rn dose of mine water in different underground uranium mines

Abstract

This paper describes the method for estimation of the contribution of mine water to 222Rn dose and its health risk using smart radon monitor with bubbler kit in Indian underground uranium mines. A significant positive correlation between 222Rn release rate and the water flow rate was also established in this paper. The geometric means of 222Rn doses in Mine 1 and Mine 3 were found to be 2.3 μSv y−1 and 9.6 μSv y−1, respectively. The arithmetic means of 222Rn doses in Mine 2, Mine 4, and Mine 5 were found to be 4.9 ± 4.0 μSv y−1, 27.1 ± 20.2 μSv y−1 and 13.7 ± 2.6 μSv y−1, respectively. The mean values of 222Rn doses in the above mines were well below the limit value of 100 μSv y−1 reported by the European Council. The average values of excess lifetime cancer risk (ELCR) in the mines varied from (5.9 ± 1.1) × 10−3 to (70.0 ± 53.3) × 10−3. The mean 222Rn-induced lung cancer cases per year per million persons (RnLCC) were found to be far below the limit range of 170–230 × 10−6 recommended by the International Commission on Radiological Protection. Therefore, mine water was found to be less contributor to the 222Rn dose in underground uranium mines.