CASS LAKE -- The United States Environmental Protection Agency has issued a record of decision for remedial action to take place at Cass Lake's superfund site in the next several years.

Superfund sites are areas designated by the EPA containing hazardous substances and pollutants that could harm local ecosystems. In Cass Lake, the site was formerly the home of a St. Regis Paper Co. facility.

The factory, on a 125-acre site, operated from the 1950s through the 1980s. During that time, the facility used creosote and other chemicals to treat wood.

Following its closure, the Minnesota Pollution Control Agency and the Leech Lake Band of Ojibwe identified contamination at various areas on the site. Since then, those agencies, as well as the EPA, have been involved in the site.

The area is located just south of the train tracks running through Cass lake. It's east of Aspen Avenue (State Highway 371), and west of Pike Bay. In the years since, the EPA has named International Paper Co. as the responsible party for the site, which was once Champion international Inc., the company that bought St. Regis.

Other responsible parties include BNSF Railroad, Cass Forest Products and the city of Cass Lake.

After contaminants were discovered, projects were launched to correct the situation. From 2004-2006, the EPA removed 3,900 tons of soil from the site. Even more contaminated soil and sludge was removed later and placed in a vault designed to hold hazardous waste on site. A groundwater pump was also constructed to treat the water.

According to a statement from the agency to the Pioneer, the contaminants of concern in the soil include dioxin and polycyclic aromatic hydrocarbons, or PAHs.

"Dioxin was used in the wood treatment process as a preservative and an insecticide at the site," the agency said. "Dioxin affects the skin and has been shown to be very toxic in animal studies and probably causes cancer."

The agency states that people could be exposed to these pollutants through direct skin contact, inhalation or ingestion. Dioxin and PAHs are of concern because some properties in the soil at levels above what the EPA considers safe. Long term exposure to these compounds may increase the risk of cancer and/or non-cancer health effects.

Remedial project details

More recently, the EPA introduced a proposal to excavate contaminated soil from residential properties on the site and back fill the area with clean dirt and new vegetation. Over summer 2019, the EPA held a comment period and in April, the agency issued a record of decision.

The project will remove contaminated soil from residential areas of the site and replace it with clean soil and vegetation. The removed soil will then be buried on nearby sites owned by either BNSF Railroad or International Paper, and covered with a liner and clean soil. The buried soil will be monitored moving forward.

As part of the process to advance the project, the EPA will negotiate with the potential responsible parties toward a cleanup agreement. Once that's complete, the EPA told the Pioneer the parties are expected to have the work plans and blueprints for the project to be ready by summer 2022. Once the design work is done, the project will be completed by either 2024 or 2025.

Before construction begins, the EPA stated it will hold public meetings with residents to discuss the upcoming work and scheduling. Additionally, the EPA will send written requests to residents for permission to access their properties for soil samples and to determine the extent of excavation needed.

When work does begin, the agency told the Pioneer that there will be a presence of work crews, heavy equipment and safety items. The latter may include traffic cones, temporary fencing and dust control equipment.