Radon Emanation from Soil and Groundwater and Surface Gamma Dose Rate in Budhakedar, Garhwal Himalayas, India.

Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India and related to the gamma dose rate in the same area. A laboratory experiment was also performed to measure the radon exhalation rate from soil samples collected from the same area. Radon exhalation rate from collected soil samples was found to vary from 0.1×10^-5 Bq·kg^-1·h^-1 to 5.7×10^-5 Bq·kg^-1·h^-1 with an average of 1.5×10^-5Bq·kg^-1·h^-1. Radon concentration in soil and groundwater of the Budhakedar area varies from 1098 to 31,776 Bq·m^-3 with an average value of 7456 Bq·m^-3, and from 8 to 3047 Bq·L^-1 with an average value 510 Bq·L^-1, respectively. Surface gamma dose rate in the study area varied from 32.4 to 83.6 μR·h^-1 with an overall mean of 58.7 μR·h^-1. The observed value of the gamma dose rate was not found to be related to the value of radon concentration in groundwater but a weak positive correlation was observed between the gamma dose rate and soil-gas radon concentration. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation with radon concentration in water. [ABSTRACT FROM AUTHOR]