It’s been just over three years since the Environmental Protection Agency formally declared the Columbia Falls Aluminum Co. plant a Superfund site — a label that cued a massive undertaking to create human health and ecological risk assessments of the site and to demolish the facility.

Those two milestones are now complete, according to project managers.

Mike Cirian with the EPA who is overseeing the project, said an Oregon-based company wrapped up tear-down efforts last week, hauling out what little remained from the above-ground portion of the facility at the base of Teakettle Mountain.

Demolition efforts began in 2015. What remains now of the multi-million dollar plant that once served as the valley’s largest employer, is administration buildings, a few warehouses, an electrical field and little else. Crews removed main structures such as the west aluminum unloader, compressor building, laboratory, the main plant building and more.

“It’s basically been completely leveled,” Cirian said. “The parts that could be salvaged were cleaned and taken away.”

Along with demolition efforts coming to an end, EPA-required human health and ecological risk assessments of the site were completed last month and sent into the agency as well as the Montana Department of Environmental Quality for review. The assessments are the first portion of a two-part research process known as a Remedial Investigation and Feasibility Study. Referred to by officials as RI/FS, the study as a whole is step three of a nine-step “Superfund process” the EPA requires to be completed in full before any Superfund site can be deemed reusable.

At its core, the two-part study is used to characterize Superfund site conditions, determine the nature and extent of potential contamination, and to assess potential risk to human health and the environment.

Representatives from CFAC and Roux and EHS Support — the two companies that worked to collect data and prepare the human health and ecological risk assessments — presented key findings to community stakeholders on Wednesday.

According to Gary Long with EHS Support, the assessments will be used to help engineers determine what areas essentially need further attention in the cleanup process — actions that will be addressed in the next feasibility study portion of the RI/FS in the coming months

For the human health risk assessment, percolation ponds on the north end of the site, operational areas between the main plant and the central landfill, and the industrial landfill are the primary areas in need of further evaluation for risk reduction. Long said “constituents of possible concern” at these areas primarily include cyanide, fluoride, and levels of PAH’s (polycyclic aromatic hydrocarbons) which is a group of more than 100 chemicals that are commonly released from the burning of coal, oil, gasoline and other elements. Cyanide and fluoride are also present in groundwater at concentrations that exceed water quality standards set forth by the Montana Department of Environmental Quality.

Those three main areas in need of further evaluation for risk to human health are the same areas identified in the ecological risk assessment, which looks at what areas may be of risk to wildlife. In addition to those areas, Long says the backwater seep area of the Flathead River and ponds may require further evaluation in the feasibility study for risk posed to aquatic life.

Long emphasized that the risk calculations for the assessments “are estimated for theoretical current use of the site and future scenarios.”

“We basically wanted to look at scenarios where humans or wildlife would come in contact with the site and what are the risks would be associated with those exposures,” Long said.

For human health, teams analyzed situations in which possible commercialization workers, industrial workers, property trespassers, recreationists and others would enter the site. For the ecological assessment, they analyzed terrestrial animals such as deer, and aquatic animals such as fish and amphibians. Then they looked at “routes” of exposure — humans drinking the water or coming into contact with soils, animals ingesting plants or sediments, and more.

The potential for humans and wildlife to experience adverse effects on the site varied greatly depending on exactly how they may come into contact with the site, how long they might be exposed, and more.

Two additional findings important to note: the ecological assessment says no other impacts to the rest of the Flathead River, either upstream or downstream are present and the human health assessment states that groundwater flows south towards the Flathead River and is not impacting nearby Aluminum City.

The process for preparing the assessments was extensive.

According to Mike Ritoro with Roux, a team collected close to 2,000 samples from soil, groundwater, and other potential points of contamination on the 1,300-acre project site and tested for countless chemicals including cadmium, cyanide, arsenic and more. They also installed 52 monitoring wells and redeveloped 20 existing wells, creating a “robust data set.”

“There really wasn’t a portion of the site that wasn’t evaluated extensively,” Ritoro said.

The entire assessment process, which was completed in two phases, has come with an estimated $60 million price tag. The bill is being footed by Glencore AG, the global commodities trading company based in Switzerland that purchased the plant in 1999.

Officials with Montana DEQ and the EPA provided stringent oversight for every inch of the project, according to Cirian.

“There were so many hands and eyes on these assessments,” Cirian said. “There were hundreds of comments on all of these initial documents and people from multiple agencies were involved.”

Moving forward, with the majority of the Remedial Investigation portion of the RI/FS complete, officials will turn their attention to the Feasibility Study. Ritoro said a work plan draft for the study, which brings in engineers to look over possible techniques for remediating the risk areas identified, will be submitted by 2020. Teams hope to have the final Feasibility Study report completed by the first quarter of 2021 after state and federal agencies have completed extensive reviews. According to Cirian, the teams are all on track to meet those deadlines.

“We definitely aren’t done yet. We have a long ways to go,” Cirian said. “But we are on schedule and we are moving ahead.”

There are six steps after the completion of the Feasibility Study before the site can be considered reuseable. Cirian said it isn’t uncommon for the Superfund Process to take a decade or longer.

The aluminum plant has long been a point of environmental contention.

In 1952, when the Anaconda Copper Mining Company first announced plans for erecting the plant, farmers, environmentalists and others were skeptical. Nevertheless, the original plant - which would later be expanded - was created a few years later to the tune of about $65 million.

By 1968, the plant was producing about 1 million pounds of aluminum per day.

But a few short years later, extensive fluoride emissions that were believed to be harming wildlife nearly six miles from the site prompted locals Loren and Mary Kreck to form a class action lawsuit against the company. The lawsuit, which sought $24 million in damages, was dismissed. However, it prompted Anaconda Co. to invest millions in the coming years on environmental controls to reduce emissions and save on power.

In 1980, the Department of Environmental Quality deems the property a “large-quantity hazardous waste generator and transporter.”

In the coming decades, the once economic powerhouse would be passed from multiple hands of ownership. In the 1980s the aluminum market faltered and owners of the plant struggled to cover operational and electrical costs.

In 2001, two years after the plant came under current Glencore AG ownership, the entire facility shut down for the first time since its inception, displacing hundreds of workers. It would start up a few years later, only to shut down again in 2009. In 2015, Glencore AG announced the permanent closing following years of steep political criticism from Sen. Jon Tester and others.

On Sept. 9, 2016, CFAC was officially labeled a Superfund site.