PSU Magazine Fall 1994

anagers at the Limerick Nuclear Power plant in the coal mining country of Pennsylvania were puzzled in 1984 when one of their employees, Stanley Watras, kept setting off the plant's radiation detectors. The detectors were set up to show whether employees leaving the plant were contaminated with radiation, which would indicate a flaw in the plant's system. In any case, it was a health hazard that would need to be fixed. The problem with Watras was that he registered unusually high radiation levels, not coming out of the plant, but going in. An investigation that followed showed that the inside of Watras' home, built above a uranium-rich geologic formation, contained enough radon-more than 2,000 picocuries per liter-to give him the equivalent lung risk, according to one source, of smoking 135 packs of cigarettes a day. Emerging from this bizarre case has been a national drive by the Environ– mental Protection Administration to map residential areas for natural-occur– ring radon, and to help the people living in those areas to clean up their homes. In Oregon, the state Health Divison has led the effort for the past six years, calling on the expertise of Scott Bums, PSU associate professor of geology, during the last three. Bums and graduate students, Stuart Ashbaugh and Bill Douglas, have done 16 PSU Magazine the most thorough testing and mapping of anyone in the country, going ZIP code by ZIP code throughout western Oregon to find the areas that pose the most risk. Bums has spoken about radon on radio talk shows, on a 30-minute KPTV program, and in December he will present a paper on the study to a national gathering of radon scientists in Denver. For professionals in the radon field, all eyes are on PSU. The Oregon Health Division began the study by randomly sampling 1,140 homes in the Portland metro area to get an idea of where the hot spots are. Bums and his team took soil samples from the same areas, then combined their findings with that of the Health Division to form the ZIP code map. The study showed that Oregon in general has a low incidence of indoor radon, but several neighborhoods are hot enough that home owners should take protective action. On their own, home owners would never know the difference. Radon, a naturally occurring form of radiation that emanates from rocks in the soil, is odorless and colorless. It seeps into a home through its foundation. Studies have shown possible links between high radon levels and lung cancer, but there are no health warning signs. Bums discovered that the areas found to have high radon levels– Alameda Ridge in northeast Portland, a hilly area in west Salem, pans of Astoria, Clatskanie and Hillsboro-had Is your house safe from naturally occurring radon? It's odorless, colorless and has been linked to lung cancer. By John Kirkland PSU geologist Scott Bums two distinct ingredients: permeable soil, and the presence of high concen– trations of uranium. Uranium is the source of the radon; permeable soil allows it to drift to the surface. Until the study, Bums says perme– able soil was not known to be as important a factor. But the more invest– igating he did, the more he found that the areas with high radon levels were places with a history of landslides or other cataclysmic events that loosened the soil. Alameda Ridge, for example, was formed 12,000 to 15,000 years ago from granite sediments deposited during gigantic floods.