Federal regulators knew potentially contaminated bark and wood chips were being sold from a Superfund site in the asbestos-tainted town of Libby, Mont., for three years before they stopped the practice, according to a letter from the Environmental Protection Agency to U.S. Sen. Max Baucus.
The Democrat asked for an investigation into the contaminated scrap piles at a defunct timber mill in response to an Associated Press story earlier this month that detailed how the wood chips and bark had been widely used as landscaping material by residents and government officials.
Asbestos from a W.R. Grace mine in Libby has killed an estimated 400 people. It's still unknown how potent the timber mill scraps were, but their prevalence around town has stoked fears of recontamination amid a government clean up that has cost more than $370 million.
The EPA previously said it learned last fall that the wood chips and bark stockpiled at the former Stimson Lumber mill were being sold by a local economic development official. In the July 14 letter to Baucus, the agency said it first found out about the sales through an October 2007 report on asbestos at the mill site.
The EPA found asbestos in samples it took from the piles in 2007 but never quantified how much. The agency is now going back and trying to gauge the health risk. Results from additional testing are expected this summer.
"EPA needs to understand it has a responsibility to earn Libby's trust and that means going above and beyond to keep folks informed," Baucus said in a statement. "Priority number one is making sure folks are safe, and these new tests will help us figure out if the wood chips are dangerous and whether more steps need to be taken to protect the community."
During the 2007 testing, four of 20 samples taken from the wood chips piles showed the presence of asbestos. Air samples from the site were negative. The results did not trigger further investigation at the time, but EPA regional administrator Jim Martin said the agency is now taking a second look at the piles.
Those will include tests designed to detect potential threats to homeowners.
The agency plans to re-analyze archived samples from its 2007 site investigation and to conduct a new round of "activity based sampling" to see if working with the material stirs up dangerous asbestos fibers.
"Our assessment to date is that it does not present a significant health risk. But we're going to do our due diligence," Martin said.
EPA spokeswoman Sonya Pennock said the agency decided to halt the sales in March because it had new information on the toxicity of asbestos in Libby. She also said the agency had been hearing concerns in the preceding months from some Libby residents about the wood chips.
"At the time it did not rise to the level of action," Pennock said when asked why the sales weren't halted earlier. "Now we have the new toxicity values and so we are going to apply those" at the former mill site.
Many of the trees processed at the mill before it was shuttered last decade came from the forests around the around the W.R. Grace mine.
EPA testing results last year showed trees up to eight miles from the mine site were riddled with asbestos. Some areas close to the mine had trees with hundreds of millions of fibers per gram of bark.
Officials also have speculated that the asbestos in the wood chip piles could have come from contaminated dust from the vermiculite mine. Residents say large quantities of dust routinely settled over Libby when the mine was still in operation.
Libby tree nursery owner Allen Olsen said Monday he has between 12 and 15 dump truck loads of the wood chips and barks spread across the grounds of his business. While he doesn't sell the material as a product, Olsen said bits of it cling to the roots of trees and other plants that he sells to customers.
"I don't want to be giving bad stuff to the public," he said. "I would like to see the truth of what's in it."
Martin wrote in the letter to Baucus that technological advances in how asbestos samples are analyzed should allow the agency to finally quantify the risk posed by the bark and wood chips.
In addition to the material used locally for landscaping and erosion control, an estimated 15,000 tons of the bark and wood chips were shipped out of Libby for use as fuel. It is uncertain where those shipments ended up.
"If there is a significant risk from the wood chips, the EPA will develop a plan to address this issue," Martin wrote.