Evaluating Uranium Depth Versus Socio-Economic Statistics for Residential Radon Vulnerability in Warren County, Kentucky

Residences in Warren County, Kentucky, are characterized by high levels of residential radon, which is one of the radioactive daughter products of uranium. According to the United States Environmental Protection Agency (US EPA), radon exposure causes approximately 22,000 lung cancer deaths in the United States per year. The City of Bowling Green, in Warren County, is underlain by karst, an easily soluble limestone subsurface, which allows radon gas to travel easily through cracks and fissures. Carbonate rocks under Bowling Green are underlain by the Devonian Chattanooga Shale, a low-grade uranium ore and a potential source of radon gas. A digital map of the Chattanooga Shale was created using Arc GIS. A 1.6 km by 1.6 km (one-mile by onemile) grid for Warren County was generated, and depth data from oil wells within each grid cell were averaged to render the elevation of the top surface of the Chattanooga Shale in a digital format. A socio-economic GIS of Warren County was created using US Census Bureau and Property Value Administration data. The Chattanooga Shale and the socio-economic layers were correlated to test points that have high residential radon measurements to determine whether proximity to the shale layer or home type is the better predictor for radon risk. Once risks have been determined, management decisionmaking is simplified and resources can be targeted towards high need areas. Although this study determined that home type, i.e., size of the home and whether there is a basement present, does have a significant effect on residential radon levels, proximity to the top surface of the Chattanooga Shale does not have a significant effect in Warren County, Kentucky. Due to this lack of a geologic pattern it is recommended that radon mitigation systems be included in all new home construction and design