Tens of thousands of tons of contaminated soil at a shuttered aluminum plant just north of Columbia Falls will be consolidated and capped under a plan released last week by the U.S. Environmental Protection Agency.
The EPA’s plan for the Columbia Falls Aluminum Company site along the Flathead River comes 15 years after the plant closed and eight years after it was added to the National Priorities List, also known as the Superfund list. The 432-page Record of Decision largely reflects a draft version that was criticized by a local group that wanted the EPA to force the site’s owner, mining giant Glencore, to completely remove the contaminated soil.
In a press release on January 10, EPA officials said the final Record of Decision marked a transition from “the investigative phase to the cleanup implementation stage at the site.” The decision was announced in coordination with the Montana Department of Environmental Quality, which supports the selected remedy of consolidating and capping the contaminants.
“This cleanup plan reflects years of collaboration and is a crucial step in finalizing a comprehensive set of cleanup actions that will protect the health of the community and the environment,” stated EPA Regional Administrator KC Becker. “In partnership with Montana DEQ and the Columbia Falls community leaders, we have worked to ensure public participation and transparency throughout the process. We are moving forward now to get the cleanup underway, protect the Flathead River and move towards a safer, healthier future for everyone who calls the Columbia Falls area home.”
As demand for aluminum increased after World War II, the Pacific Northwest, with ample access to hydroelectricity, became an epicenter for the industry with 10 large plants scattered across Washington, Oregon and Montana. At one point, more than 11,000 people worked in aluminum production in the region. In 1955, the Anaconda Copper Mining Company opened CFAC at the base of Teakettle Mountain, just a few miles away from its primary power source, the newly constructed Hungry Horse Dam. The plant eventually became the largest employer in Flathead County.
While the plant secured Columbia Falls’ spot as the industrial hub of the Flathead Valley, CFAC’s environmental impacts were soon obvious. In 1969, U.S. Forest Service researchers began to report on the negative impacts of fluoride emissions from the facility on plants and wildlife. Other contaminants, including sodium and cyanide, were also discovered.
Ownership of the plant changed multiple times through the second half of the 20th century, finally being acquired by Glencore in May 1999. Amid a spike in electricity costs, Glencore idled the plant in January 2001. A year later, the plant was restarted but not to full capacity. It remained open until October 2009 when production was halted for good. In September 2016, after years of back-and-forth between Glencore and local, state and federal officials, CFAC was designated a Superfund site.
The Superfund site extends for approximately 1,340 acres (not all of the land owned by Glencore), but most of the estimated 1.2 million cubic yards of contaminated soil are focused on 200 acres near the plant’s former landfills where waste from the aluminum smelting process was disposed. In 2023, the EPA released a preliminary plan that called for leaving most of the waste in place and surrounding it with a slurry wall. The concrete wall below the surface would help prevent groundwater from traveling through the landfills. A report from the EPA states that contaminants from the site have not impacted the nearby Flathead River.
But a local group called the Coalition for a Clean CFAC was critical of that plan and urged the EPA to have the toxic soil excavated and moved to a landfill in Oregon. EPA officials stated that the proposal was considered but ultimately rejected due to cost and the risks related to transporting that material either by track or by train.
Peter Metcalf, a Columbia Falls resident and board member for Coalition for a Clean CFAC, said Monday that he was disappointed that the final Record of Decision was mostly unchanged from the EPA’s initial draft and that the toxic material would remain on site. He said that Glencore, one of the world’s largest mining companies, had the resources to clean up the site appropriately.
“We’re obviously disappointed that the EPA has put Glencore’s interests over those of the Columbia Falls community,” he said.
While the final Record of Decision was a major moment in the saga of the CFAC Superfund, Metcalf said his group planned to remain involved in the process moving forward.
The consolidation and capping of the soils at the site are expected to take two to four years and cost Glencore an estimated $57.6 million. Groundwater on the site will also be monitored in the future to ensure the remedy is working. The EPA is now working on a consent decree with Glencore to enact the plan.
Last year, Glencore announced that it planned to sell the land around the former aluminum plant site to local developer Mick Ruis. The sale was contingent on the EPA releasing a Record of Decision, with some of the land being transferred following its release and the rest after the cleanup. Ruis plans to develop the land for commercial, industrial and residential uses.
