Anomalously high levels of uranium and other naturally occurring radionuclides in private wells in the piedmont region of South Carolina

Anomalously high levels of uranium and Pb-210 have been detected in untreated domestic groundwater wells near Simpsonville/Fountain Inn, South Carolina. Nine wells were sampled from the affected area and analyzed for total uranium, U-234,U-235,U-238, Ra-226,Ra-228, Rn-222, and Pb-210 as well other water quality parameters. These data augment other uranium concentration measurements and limited Ra-226,Ra-228 and Rn-222 concentration measurements collected on private and public wells by the South Carolina Department of Health and Environmental Control. The observed radionuclide data were compared to maximum levels published in several national surveys from the past 30 years. The total uranium concentration in the groundwater ranged from 44.3 to 5,570 mug L-1, with one well having the second highest published concentration in the U.S. The U-234/U-238 activity ratio ranged from 1.1 to 2.5. Ra-226 concentrations ranged from less than the minimum detectable concentration (< MDC) to 1,154 mBq L-1 while the Ra-228 concentration ranged from < MDC to 532.8 mBq L-1 and the Rn-222 levels ranged from 62 to 1,510 Bq L-1. The Pb-210 concentrations ranged from < MDC to 844 mBq L-1.