BILLINGS, Mont. (AP) — Federal officials have entered discussions with W.R. Grace & Co. over how to clean up asbestos washing into the Kootenai River from a deadly vermiculite mine the company owns in northwest Montana.
More than 20 years after the Maryland-based Grace closed the above-ground mine near the town of Libby, tests results provided by federal regulators show high amounts of asbestos pouring from the creeks inside the mine site during the annual spring snowmelt.
The creeks drain into the Kootenai (KOOT'-nee) just upstream of Libby, where an estimated 400 people have been killed and 1,750 sickened by asbestos dust released when vermiculite ore was mined to make residential insulation.
The consequences of inhaling Libby's potent asbestos fibers are well documented and include lung cancers and other fatal diseases. Much less is known about the dangers of ingesting the fibers and their potential harm to wildlife.
U.S. Environmental Protection Agency regulators said they are trying to gauge the risk from the water-borne asbestos. They have yet to determine how far downriver the contamination might extend.
"We are still looking to acquire data to tell us what the risks would be at the concentrations that we're seeing," said EPA project manager Christina Progess.
Some Libby residents said they worried the contaminated water could prolong a cleanup that has cost more than $370 million over the past decade.
At the mine site, one water sample taken from Rainy Creek in May showed 276 million asbestos fibers per liter of water.
Several miles downstream, water pumped from the Kootenai in Libby is used in the cleanup to suppress dust and for equipment decontamination. EPA officials said 10 samples taken in recent months did not detect any asbestos in the pumped water.
W.R. Grace vice president William Corcoran said in a statement that the company has been working for several years to come up with a plan to remediate the mine site, including Rainy Creek. He said the company was cooperating with the EPA and that discussions were continuing.
The waterway that appears most contaminated is Rainy Creek, with asbestos readings well over the drinking water health standard of 7 million fibers per liter. Only larger asbestos fibers are counted for the drinking water standard. The highest count for those larger fibers in Rainy Creek was 55 million fibers per liter on May 17.
The Kootenai River isn't the drinking water source for Libby, nor are any of the creeks that come from mine — the city gets its water from another tributary of the river.
However, the test results from Rainy Creek are "huge" and could pose risks to populations that live anywhere along the Kootenai between Rainy Creek and the Pacific Ocean, said Phillip Erquiaga with the Libby Area Technical Advisory Group, an EPA-funded cleanup oversight panel.
The sample results draw attention to an aspect of Libby's cleanup that often has been overlooked, with more attention given to asbestos dust that tainted the town's homes, businesses, parks and schools. "You go down to the Kootenai River and go to any shoreline that has a sandy bank and pick up some dirt and you'll find it's got vermiculite in it," Erquiaga said.
Montana Department of Environmental Quality director Richard Opper called the test results "troubling." He said he wants EPA and Grace to move quickly to stop further contamination of the water at the mine site.
State officials said berms along the creeks, more vegetation and other measures could be used to stop asbestos-tainted sediment from entering the water. No penalties or other enforcement actions were being considered.
"We need to get some stuff in place now to stop the bleeding. I fully expect EPA and Grace to be cooperative. And if they're not, we'll take another look at enforcement," Opper said.
Progess said likely sources of asbestos in the water are exposed mine waste and tailings piles that extend to a creek on the property. Test results from the 1990s that were recently provided by W.R. Grace showed similar levels of asbestos — "in the 200 million fibers per liter range," said Progess.
Asbestos levels drop off sharply outside of spring runoff. The only test results provided by the EPA for the Kootenai River were taken during low water in 2008. Those showed low levels of contamination.
Low levels also were found in a sandbar on the Kootenai just below Rainy Creek, Progess said.
EPA contractors over the past decade have hauled hundreds of truckloads of contaminated soil from residences in Libby to the mine site for disposal. Because most of Rainy Creek and everything else within the mine site is closed to public access, it is unclear how fast that contaminated soil is eroding.
A Montana DEQ official assigned to the cleanup said the soil is considered less hazardous than exposed ground at the mine that has a higher concentration of asbestos.
"The intent is to cover up the really bad stuff with soil that has a low asbestos content," said DEQ environmental scientist John Podolinksy.
Two toxicity studies to find out if fish in the creeks were being harmed were unsuccessful. Progess said asbestos fibers in the test clung to equipment such as the tanks that held the fish, making it impossible to simulate what was happening in the creeks around the mine.