Quantification of radon concentration in groundwater around abandoned Gogi uranium mineralized zone, Yadagir district, Karnataka, India

Radon activity concentrations have been measured by analysing a total of 93 bore well water samples, geographically spread over three taluks of Yadagir district. The analysis involved usage of Durridge’s RAD7 radon analyser equipment with RAD-H2O accessories by closed loop aeration concept. Having geometric mean concentrations of 37.0, 20.75 and 9.98 Bq/L, radon concentration in 5.71, 14.29 and 6.67% groundwater samples from Yadagir (8.88 Bq/L < Rn < 160 Bq/L), Shahapur (1.98 Bq/L < Rn < 591 Bq/L) and Surpur (0.586 Bq/L < Rn < 206 Bq/L) taluks respectively exceeded the alternative maximum contaminant level (AMCL) of the USEPA (148 Bq/L). Nearly 15% of the groundwater samples had radon concentrations higher than WHO reference level of 100 Bq/L. The calculated total annual effective dose in 38.71, 44.09, and 55.92% of the samples respectively for infants, children and adults was not in consistent with WHO recommended dose level of 100 µSv/y.