Estimation of distribution coefficient of uranium around a uranium mining site

Distribution coefficient (K _d) of uranium and its daughter products are very important for migration study around uranium mining sites. Since the distribution coefficient depends very much on the soil and groundwater chemistry, generation of site specific K _d is very important. In the literature there is a large variation of K _d values of uranium. For realistic prediction of contaminant migration, literature K _d value is not very effective. So site specific experimental K _d values are required. The present study emphasizes on the estimation of site specific distribution coefficient for uranium around a uranium mining site. The soil and groundwater parameters which affect the K _d value of uranium have also been estimated. Soil and groundwater samples from nine locations around Turamdih uranium mining site were collected and chemically characterized for various parameters. The distribution coefficient of uranium in top and one meter depth soil samples from above locations were estimated using laboratory batch method. The distribution coefficient of uranium varies from 69 ± 4 to 5524 ± 285 l/kg. No significant difference in uranium K _d values was observed for top and one meter depth soil samples. In the top and one meter depth soil samples uranium K _d values vary from 129 ± 8 to 5524 ± 285 and 69 ± 4 to 3862 ± 195 l/kg respectively. For the estimation of distribution coefficient of uranium different parameters like equilibration time, solid to solution ratio, method of tracer addition to solution, solid-solution separation method etc. have been optimized. The distribution coefficient of uranium determined in the present study will be used for the migration study of uranium around uranium mining sites.