Feds Release Proposed Cleanup Plan for CFAC Superfund Site

Years-long investigation of former home of Columbia Falls Aluminum Co. approaches final stages with EPA’s release of $57.5 million remediation plan; public meeting scheduled for June 28

By Tristan Scott
Columbia Falls Aluminum Company. Hunter D’Antuono | Flathead Beacon

The U.S. Environmental Protection Agency (EPA) on June 1 released a proposed cleanup plan for the Columbia Falls Aluminum Company (CFAC) Superfund site, touching off a 60-day period during which the public can review and comment on the $57.5 million proposed project that entails treating soil contamination and constructing a slurry wall to keep chemicals from running into nearby waterways.

The EPA’s selection of a preferred cleanup plan signals a critical step in a years-long process to craft a solution for the contaminated site. The proposal comes two years after CFAC, which shuttered its pant in 2009, received EPA approval of its 538-page feasibility study, laying the groundwork for the federal regulatory agency’s selection of a preferred project alternative and triggering a 60-day public comment period.

In a June 1 announcement by EPA, the federal regulatory agency identified a preferred option, which is projected to cost $57.5 million and involves building a slurry wall to contain the release of environmental hazards such as cyanide and fluoride from buried waste at the shuttered aluminum plant’s former landfill, as well as address groundwater issues.

The proposed plan also divides the site into six so-called decision units where remediation is needed — at two landfill sites, on a soil project, at the north and south percolation ponds, in the groundwater, and along the Flathead River — and describes a range of proposed remediation tactics. EPA is seeking public comment on those recommendations and will then issue a record of decision that will guide the construction design and cleanup to follow. It is at that point that remediation work is anticipated to begin in full.

Contractors place rolls on the riverbank as part of a project by the Columbia Falls Aluminum Company to restore the Flathead River to its natural channel. Courtesy photo

According to a timeline included in the proposed plan, the cleanup project’s design is anticipated to take six to 12 months, while construction of the project, including the slurry wall, monitoring wells, on-site repository, groundwater treatment technologies, and fencing — will span one to two construction seasons. Maintenance of the site would be ongoing and environmental reviews would be set every five years.

Located two miles northeast of Columbia Falls on the Flathead River, the CFAC site was once home to an aluminum reduction facility. The primary contaminants of concern are fluoride, cyanide and various metals. EPA’s proposed plan describes the actions the federal government deems necessary to protect human health and the environment from contaminants present in landfills, surface water and groundwater at the site.  

From its famous opening in 1955 through the boom years of the 1960s and 70s, the facility fueled this rural corner of Montana with over 1,500 jobs — almost half the population of Columbia Falls in those days — and millions of dollars in new economic investment. The plant closed in 2009, putting hundreds of employees out of work. The EPA declared it a Superfund site in 2016.

A public meeting will be held on June 28 from 6:30 p.m.-8:30 p.m. at the Columbia Falls Town Hall, City Council Chambers, 130 6th St. W., to describe the proposed plan and solicit comments before a Record of Decision Amendment is released later this year.

Other in-person outreach opportunities will be provided during the comment period by EPA staff and technical advisors with the Technical Assistance Services for Communities program. These opportunities include public meetings scheduled for June 21 and July 12 at the Columbia Falls Town Hall occurring at noon and 6:30 p.m. on both days. 

Both written and oral comments will be accepted and recorded at the public meeting on June 28.

Written comments can also be sent by email to Missy Haniewicz at [email protected] or by standard mail to Missy Haniewicz, U.S. EPA, 1595 Wynkoop Street, Denver, Colorado, 80202.  

The proposed plan, associated documents and information on how to submit comments can be found at the Columbia Falls Superfund site webpage.