Respirator-wearing technicians from the U.S. Environmental Protection Agency were back testing for asbestos this week near W.R. Grace’s former Zonolite factory in Spokane.
During soil testing in June, the agency found low levels of the cancer-causing fibers in residential yards near the former Vermiculite Northwest plant at 1318 N. Maple St.
Now, EPA officials want to know if routine yard activities – such as shoveling dirt or raking – could cause the asbestos fibers to become airborne.
“We’re simulating what people could do on their property,” said Greg Weigel, on-scene coordinator for EPA’s environmental cleanup program. “What we’ve learned from other sites, including Libby, Montana, is that even low levels of asbestos in soil could pose a risk if the asbestos is susceptible to becoming airborne.”
For 22 years, Vermiculite Northwest produced Zonolite, an asbestos-tainted attic insulation. Rail cars brought vermiculite ore from Libby to the plant, where furnaces heated the ore until it puffed up into lightweight insulation.
W.R. Grace closed Vermiculite Northwest in 1973, after a whistle-blower tipped state inspectors to high asbestos levels inside. Spokane County’s road department bought the property, which was capped with asphalt as part of the site cleanup.
Earlier this year, EPA declared a public health emergency in Libby, where contamination from a now-closed vermiculite mine has been cited in the deaths of more than 200 people. Thousands more are believed to suffer from asbestos-related illnesses, including asbestosis and mesothelioma, a cancer of the lung lining.
EPA has identified 271 sites nationwide where W.R. Grace turned vermiculite ore from Libby into insulation. The agency’s screening efforts have focused on 105 sites – including the Spokane site – which received 95 percent of the ore.
EPA tested two yards and some county-owned property in Spokane over a three-day period. The work concluded Wednesday. Initial results should be available within six weeks, but additional assessment will be needed to calculate potential health risks, Weigel said.