CFAC cleanup talks get underway

The first public views of the proposed cleanup plan for the Columbia Falls Aluminum Co. Superfund site came to light at meetings last week.

CFAC officials have endorsed the EPA’s proposed action plan for a cleanup of the site. Meanwhile, Karmen King, an independent technical advisor suggests the plan could be further bolstered to protect ground and surface water both on and off the site.

King is a third-party analyst with Technical Assistance Services for Communities, a program designed to help communities dealing with Superfund sites.

The proposed action has several facets, but the main thrust is to contain the worst dumps — the west landfill and the wet scrubber pond — by fully surrounding them with a slurry wall to stop contaminated groundwater from leaching from them.

The wells at the former wet scrubber sludge pond and the west landfill have the worst contamination. Test wells near them have very high concentrations of fluoride and cyanide, from spent potliner that was dumped there for decades.

Potliner is a carbon material that, like its name implies, lined the pots that the aluminum was smelted in.

Until at least 1970, possibly longer, the potliner was simply dumped at the almost 8 acre west landfill, which was unlined. Over time, the cyanide and fluoride leach from the potliner into the groundwater. The other main polluter is the wet scrubber sludge pond, which is about 10 acres, where wastewater from the plant was pumped into an unlined pond. It too, is a major source of contamination.

The slurry wall, ranging from 100 and 125 feet, would encompass both of the above-mentioned dumps. In addition, the west landfill and wet scrubber pond would be capped with a low permeable material to keep more water from seeping into them.

The slurry would likely be made of bentonite and existing soils. In short, it would be designed to keep the contaminated groundwater from leaching beyond the dumps.

But King, in her analysis of the proposed action, suggests the slurry wall should be expanded to include another landfill — the center landfill, which is just to the east of the old wet scrubber sludge pond.

The center landfill is also a source of groundwater contamination, but the plan calls for capping it, not encompassing it behind the wall.

(The pond no longer has surface water. It looks like a grassy field).

“It seems prudent to consider a more comprehensive encompassing slurry wall feature that could address all three of the significant groundwater contamination features,” King writes in her report on the proposed action.

But CFAC project manager John Stroiazzo noted the company looked closely at the center landfill in the feasibility study.

He cited the study, which found minimal cyanide leaching from the landfill.

“The contribution of the center landfill to cyanide concentrations in groundwater is minimal, if any. Furthermore, historical documents indicate that the center landfill was constructed approximately 15 feet above the surrounding grade and the groundwater in that area ranges from 57 to 139 feet below the surrounding grade. Therefore, it is highly unlikely that material impacted by the center landfill extends to groundwater, so a slurry wall cutting off groundwater flow to the area under the center landfill wouldn’t have any impact on groundwater quality,” he said in a subsequent email to the Hungry Horse News.

It is important to note that King’s suggestions are not formally presented to the EPA — it’s up to the members of the public to present them to the EPA.

King makes several more suggestions in her 10-page report, most of which deal with properly controlling surface runoff so that it doesn’t compromise the caps of landfills at the site (the site has a total of nine), closely monitoring the site, and addressing future and current impacts to wildlife.

She also has concerns that the slurry wall could change the groundwater flow and suggests that it be closely monitored, not just at the landfills which are known to be the worst offenders.

“The slurry wall will prohibit groundwater migration across the wall into the waste area, and act as an obstacle for groundwater movement; forcing the water to travel around and/or below the wall (if the wall is not tied adequately to the underlying bedrock). This flow pathway may alter the effectiveness of using down gradient wells for monitoring depending on the well development specifications. In addition, the altered flow pathway may create a new groundwater route that could encounter unknown, buried wastes etc. It seems appropriate to ensure that the ‘groundwater effectiveness monitoring’ program should be robust enough to capture all possible future pathways, and to include a thorough list of all possible contaminants that may be encountered,” King suggests.

King, however, does not suggest the waste be removed entirely.

Two former employees, Nino Berube, who was a longtime engineer at the plant, and Mike Shepard, a city councilman who also worked at the plant, argued during a meeting with Technical Assistance for Communities staff that the waste should not only be removed entirely, but more testing needs to be done.

Both men brought up a myriad of instances where contaminants were dumped at the site. The cited a fire that burned for days, releasing contaminants into soils, old rectifiers that were buried that were full of mercury switches and dry wells that they said are still buried under the parking lot.

They also argued that if the owners of the plant were capable of hauling potentially harmful substances into the plant for decades, they were certainly capable of paying to haul them out.

But that hasn’t been the strategy of cleaning up other aluminum plants in the Pacific Northwest. At the Kaiser Mead plant near Spokane, Washington, the EPA capped landfills and consolidated waste. It continues to treat the groundwater for cyanide and fluoride; at the Martin-Marietta plant in Dalles, Oregon, it’s a similar situation, with consolidated landfills and contaminated groundwater that’s being treated.

The Dalles site has been taken out of the Superfund listing, but monitoring continues.

Aluminum plants all have one thing in common — cyanide, a deadly poison and fluoride. Both are byproducts of the production process.

At a CFAC liaison panel meeting last week, city manager Susan Nicosia asked about when the discussion should begin about redevelopment.

The city has eyed at least some of the 3,000 acre CFAC property for eventual housing development outside of the Superfund area.

Project manager John Stroiazzo during a tour after the meeting said a local company is housing its aircraft in one of the remaining warehouses and there have been a lot of inquiries about the site.

He said the company would have better answers after a record of decision and consent decree are finalized with the EPA.

The record of decision lays out the final plans for the cleanup; while the consent decree determines the legal and financial parameters of the cleanup. Consent decrees can take years to negotiate, but Stroiazzo noted the company only took a few months to negotiate the initial consent decree that outlined the initial testing, investigation and remedial studies.

CFAC isn’t the only responsible party, however. A federal judge in 2021 ruled that former owner the Atlantic Richfield Co. was responsible for 35% of the costs.

From a public standpoint, the rubber meets the road this week, as the EPA will be in town Wednesday (today) to discuss the plan and take formal comments.

It is important for the public to know that all comments received will be answered in writing by the EPA.

The EPA meeting on the proposed action from 6:30-8:30 p.m. (tonight) at the Columbia Falls City Hall to talk about the proposed plan and solicit comments before a Record of Decision Amendment is released later this year.

King is expected to be in Columbia Falls July 12 for a followup meeting, with meetings at noon and 6:30 p.m. at city hall.

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

Written comments can also be sent by email to Missy Haniewicz at haniewicz.melissa.m@epa.gov or by standard mail to Missy Haniewicz, U.S. EPA, 1595 Wynkoop Street, Denver, Colorado, 80202.