Asbestos levels in Libby’s air are low enough that they don’t pose a significant cancer risk, according to a two-year study presented at Monday’s town hall meeting by the Environmental Protection Agency.

“The levels are much, much, much lower than when the mine was operating years ago,” Libby Team Leader Victor Ketellapper said during the meeting.

The Libby Asbestos Site’s annual project update served to inform the public on the agency’s long-term site strategies, as well as to take questions and talk about what has been accomplished so far. Three representatives, including Ketellapper, from the EPA’s Region 8 headquarters in Denver, Colo., were on hand, as well as Catherine LeCours of the Montana Department of Environmental Quality and Mike Cirian, the EPA’s onsite project manager.  

The final draft of the results of Libby’s outdoor ambient air study was released Monday just in time for the meeting. The study took air samples from 18 locations in and around Libby, as well as additional reference samples in Helena and Eureka, from October 2006 to June 2008, to determine the levels of Libby amphibole.

Ketellapper told attendees that the risk of developing cancer from inhaling outdoor air in Libby is one in 1 million.

During the question-and-answer period, an attendee said he believes EPA’s science has limitations. The community member said – and it’s outlined in the study – that the level of asbestos that is considered toxic enough to cause cancer is based on the mineral chrysotile, not the mineral in Libby amphibole. Studies suggest amphibole is more dangerous.

After being pressed, Ketellapper agreed that the science is not perfect, but that it will take years to perform the studies to determine the level of toxicity of Libby amphibole.

“Do you think this community can wait for that?” Ketellapper fired back. “At this point, we have to go forward with the data we have.”

The EPA reported no statistically significant differences between Helena’s concentrations of Libby amphibole and Libby’s concentrations. However, parts of Libby had slightly higher concentrations than Eureka.

The study also found that Libby amphibole levels were slightly lower in the winter than the summer, confirming hypotheses that releases are lowest when the ground is frozen or snow-covered, and highest when the ground is dry.

The EPA conducted sampling at 14 stations in Libby’s residential and business district, or Operable Unit 4, the first year. Believing that the number of stations in OU4 could be decreased, the EPA retained seven of the stations the second year and extended sampling to Operable Unit 2 – the former screen plant – and Operable Unit 6 – the Burlington Northern Santa Fe Railroad property.