Private well groundwater quality in West Virginia, USA-2010

The Centers for Disease Control and Prevention (CDC), in collaboration with the West Virginia Bureau of Public Health (BPH), initiated an investigation to characterize private well water quality in West Virginia. The objective was to better characterize private well water across various aquifer geologies by testing household drinking water samples and comparing them to EPA's National Primary Drinking Water Standards. The BPH selected ten counties representing three regions to capture geologically diverse areas that represent varying aquifer geology. We collected well-water samples from participating households and analyzed all water samples for 20 constituents currently monitored in public drinking-water systems. We calculated geometric means for each constituent and compared metal concentrations to EPA maximum and secondary contaminant levels by the geologic age of the rock surrounding the aquifer where the sample was obtained. All participating households (n=139) provided a water sample. We detected arsenic at levels higher than the EPA maximum contaminant level in 10 (7.2%) samples. We detected elevated radon-222 in 48 (34.5%) samples. Geologic age of the region was indicative of whether arsenic and radon-222 were present at levels that exceeded current EPA drinking water standards. We found arsenic and radon concentrations were higher in Permian aquifers compared to those of other geologic ages. Homeowners with private wells in areas with Permian aged aquifers could benefit from targeted public health messaging about potentially harmful constituent concentrations in the well water. This may help ensure proper testing and maintenance of private wells and reduce exposure to these constituents.