Jul. 18—Libby and Troy may soon hit what federal officials described as a milestone in asbestos cleanup efforts, despite reservations from some community members.
Enviornmental Protection Agency officials classified conditions in both towns as “protective of human health and the environment” during an inspection in October 2024. Dania Zinner, the remedial project manager for the Libby Asbestos Superfund site, suggested that the recent designation could prime Libby and Troy for removal from the agency’s National Priorities List, which currently includes more than 1,000 of the most contaminated sites in the United States.
“We’re really seeking community input on whether we’re ready to do that,” said Zinner at a July 15 meeting reviewing outcomes from the five-year inspection.
If delisted, the towns would remain under the umbrella of the Superfund site, and existing funding for the treatment of asbestos-related diseases and cleanup efforts would remain intact.
“It’s basically just a milestone,” Zinner said of the potential delisting. “There’s not impacts to anything that’s going on right now.”
But the decision could still represent an important ceremonial landmark for an area long plagued by a legacy of contamination.
Federal officials established the Libby Asbestos Superfund site in 2002 after discovering that vermiculite mined in the area was contaminated with a particularly dangerous form of asbestos. Mine workers and nearby residents that were exposed to what is now known as Libby amphibole asbestos developed lung diseases at rates “staggeringly higher than the national average,” prompting the Environmental Protection Agency to declare a public health emergency in 2009.
In the following decades, federal officials removed more than one million cubic yards of dirt and 30,000 cubic yards of building materials contaminated with asbestos from homes, schools and parks in the area.
In 2019, the environmental agency removed the former screening plant for the mine from the National Priorities List. The former export plant, the BNSF railyard and the Stimson Lumber Company mill have also been partially or fully delisted after cleanup activities concluded.
But, in letters addressed to the Enviornmental Protection Agency, some physicians and researchers argued that delisting residential areas in Troy and Libby was preemptive as many of the long-term health risks of Libby amphibole asbestos exposure remain uncertain.
“Much new information has come to light regarding [Libby amphibole asbestos] in the past 10-12 years,” read several of the letters. “These new understandings make it currently impossible to say whether the site is safe.”
The writers, which include three current and former physicians at the Center for Asbestos-Related Diseases clinic in Libby and a researcher from Montana State University, specifically draw attention to a potential link between autoimmune diseases and exposure to Libby amphibole asbestos.
“That’s definitely something that’s on our to-do list, to look at the autoimmune data that was provided to us,” said Zinner at the public meeting on Tuesday.
She reported that the federal agency has already contacted the Agency for Toxic Substances and Disease Registry for assistance reviewing data from the asbestos clinic in Libby. Those results could be available as early as October 2025, though further research would likely be necessary if a trend is observed.
“This is not an unusual problem. This is something the agency does all the time,” said toxicologist Jason Fritz.
He said that the federal agency uses numerical estimates called reference concentrations to determine how much of a substance an individual can be exposed to “without an appreciable risk of deleterious effects during a lifetime.”
When the reference concentration for Libby amphibole asbestos was established in 2014, Fritz said there was “some evidence” of an association between autoimmune diseases and asbestos exposure, but not enough for researchers to definitively prove cause-and-effect. To account for that and other unknowns, researchers included what Fritz called an “uncertainty factor,” resulting in an especially conservative reference concentration for Libby amphibole asbestos.
Zinner added that the federal agency was “not even going to talk about” lifting the public health emergency in Libby until cleanup operations concluded in the area surrounding the former vermiculate mine. Designated Operable Unit 3, the approximately 10,000-acre swath of land northeast of Libby is the only portion of the Superfund site that has not yet undergone cleanup efforts.
The Environmental Protection Agency anticipates releasing a proposed cleanup plan for the unit in 2027.
Reporter Hailey Smalley may be reached at 758-4433 or hsmalley@dailyinterlake.com.