Natural radioactivity in ground water near the Savannah River Site

Abstract

A study of natural radioactivity in groundwater on and adjacent to the Savannah River Site (SRS) in Aiken (SC) was conducted to determine the spatial and temporal variations in the concentration of specific radionuclides. All available measurements for gross alpha particle activity, gross beta activity, uranium, Ra-226, Ra-228, and radon were collated. Relatively few radionuclide-specific results were found. Twenty samples from drinking water supplies in the area were collected in October 1987 and analyzed for U-238, U-234, Ra-226, Ra-228, and Rn-222. The aquifer type for each public water supply system was determined, and statistical analyses were conducted to detect differences among aquifer types and geographic areas defined at the country level. For samples from the public water wells and distribution systems on and adjacent to the site, most of the gross alpha particle activity could be attributed to Ra-226. Aquifer type was an important factor in determining the level of radioactivity in groundwater. The distribution and geochemical factors affecting the distribution of each radionuclide for the different aquifer types are discussed in detail. Statistical analyses were also run to test for aerial differences, among counties and the site. For all types of measurements, there were no differences in the distribution of radioactivity among the ten counties in the vicinity of the site or the site itself. The mean value for the plant was the lowest of all geographic areas for gross alpha particle activity and radon, intermediate for gross beta activity, and in the upper ranks for Ra-226 and Ra-228. It is concluded that the drinking water quality onsite is comparable with that in the vicinity. 19 refs., 5 figs., 5 tabs.