Notable case, Libby, Montana, United States
Libby Asbestos Site
A vermiculite mine that may have supplied 80% of world output; the ore was contaminated with a highly friable amphibole asbestos that spread into homes, soil and air in Libby and Troy.
At a glance
- Status
- Remediation under way
- Activity
- 1920–1990
- Media
- soil, air, living organisms
- Kind of site
- mining, asbestos
- National list
- Listed 2002National Priorities List
- Area. The site covers the towns of Libby and Troy, the former mine and the surrounding forest; the source consulted gives no overall area.
Contaminants
Fibres
National list
On the list (final)United States
Superfund National Priorities List (NPL)
- Listed
- 2002
- Official id
- MT0009083840 ↗
About this list
The list of contaminated sites that are national priorities for federal clean-up under CERCLA (Superfund, 1980), kept by EPA (40 CFR Part 300, Appendix B). Listing makes a site eligible for long-term remedial action paid by the Superfund; sites are proposed and then listed through Federal Register notices, and deleted when no further response is needed.
Includes federal facilities (Defense, Energy). Dates are the years of the Federal Register notices (final listing, deletion); 'listed' is empty for proposed sites. Some sites still on the list have had partial deletions. Contaminants and media: contaminants of concern from decision documents (RODs, ROD amendments, ESDs; EPA, fiscal years 1981-2024, SEMS document HQ/406315); for sites with no decision document (mostly proposed or recently listed) the contaminants are those EPA records for the site (FOIA-015, document HQ/406366), with no medium. 'Deleted' means EPA found no further response needed, which can include land-use controls still in force.
Status
Remediation under way
By 2018 EPA had finished investigating and cleaning most of the site; the former mine and nearby forest (Operable Unit 3) remain, with a feasibility study under way. The third five-year review dates from 2025.
Story
Vermiculite was found at Libby in 1881 and from the 1920s the Zonolite Company mined it. W.R. Grace bought the operation in 1963; it closed in 1990. The vermiculite, used as building insulation and soil conditioner, was contaminated with asbestos of the tremolite-actinolite series, now called Libby Amphibole.
In 1999, after concerns raised by citizens, local government and the press, EPA began investigating, and removals started in 2000. The asbestos was found in indoor and outdoor air, insulation, house dust, soil, water, animals and fish. In 2009, for the first time in its history, EPA and the Department of Health and Human Services declared a Public Health Emergency, which gives federal health care to people with asbestos-related disease.
By November 2018 EPA had investigated more than 7,600 homes and businesses, cleaned over 2,600 of them and removed more than one million cubic yards of contaminated soil, which was placed in the former mine. According to EPA, asbestos in the air of downtown Libby is now nearly 100,000 times lower than when the mine and mill were running.
Timeline
- 1881Vermiculite discovered at Libby.
- 1963W.R. Grace buys the Zonolite mine.
- 1990The mine closes.
- 1999EPA begins investigating.
- 2002Placed on the National Priorities List.
- 2009Public Health Emergency declared; W.R. Grace acquitted in the criminal trial.
- 2018Cleanup of homes, schools, parks and commercial areas completed.
Health
EPA states that Libby Amphibole causes lung cancer, mesothelioma and other lung disease, and has been associated with systemic autoimmune or autoinflammatory disease. The specific toxicity review dates from 2014 and the human health risk assessment from 2015.
Remediation
- 2018excavation and removalFrom 2000 to 2018: more than one million cubic yards of soil and over 30,000 cubic yards of contaminated building material removed from more than 2,600 properties.
Nearby
Notable case, Kellogg, United States
Bunker Hill Mining and Metallurgical Complex
103 km
Phytoremediation
Notable case, British Columbia, Canada
Trail Smelter
177 km
- Sulphates
Notable case, Montana, United States
Butte (Berkeley Pit and Silver Bow Creek)
349 km
Notable case, Richland, United States
Hanford Site
360 km
- Plutonium
- Uranium
- Tritium
- Strontium-90
Phytoremediation
Sources
- Libby Asbestos Site, Libby, MT – Cleanup Activities, US EPA, 2026
- Libby, Montana, Wikipedia, 2026
Draft compiled from public sources, not yet reviewed.