WATERBORNE RADON IN WELL WATER FROM COMMUNITY WELLS IN NORTHERN VIRGINIA

Uranium and the decay products of uranium are present in most well water of the Appalachian Mountain states. Often, one of the decay products, radon, is present in amounts tht greatly exceed the US-EPA recommended MCL of 300 pCi/L. Radon and its associated radioactive elemments constitute the majority of our natural radiation dose from both air and water. Studies sugest that at the common levels of 3000 pCi/l in well water, there is a significant increase in the incidence of blood and other types of cancer. To comply with US-EPA requests, Prince William County in northern Virginia obtained measurements of waterborne radon several times over two years at many of the water wells used for communities of residents. Measurements were taken at the large community storge tanks and the kitchens of homes served by these wells. Since it was possible to determine the type of rock in which each well was sited, compilations for the major rock types were made. In brief, wells in Paleozoic granite averaged more than 3000 pCi/l, wells in Paleozoic schist and in Mesozoic red sandstone averaged about 1500 pCi/l, and wells in Cambrian metasandstone averaged about 1000 pCi/l. Comparisons between community storage tanks the surrounding homes revealed that only about 30% of the radioactivity was lost in transit. Although these conclusions were provided to county residents, little was done by homeowners to remediate their situation. Surveys revealed that their lack of concern was most often because: (1) radon has no taste, so consumer evidence for excess radon is not evidence, (2) consumers do not notice excess cases of cancer in their community, and (3) radon removal systems cost more than most want to pay ($2000-$4000).