The Wisconsin Public Service Corp. will now be responsible for cleaning up chemical contamination in Marinette after a settlement with the state and federal governments.
WPS will be responsible for cleaning up historic contamination of polycyclic aromatic hydrocarbons, or PAHs, at a former manufactured gas plant, according to a Monday afternoon release from the Department of Justice.
The settlement was reached on Friday and requires the utility to conduct remedial activities at the site, dredge and dispose of contaminated sediments, and perform long-term monitoring to assess how successful the cleanup is, according to a release from the DOJ. The complaint was filed against the company in May.
In addition to ongoing cleanup efforts, WPS will also be required to pay for all future costs incurred by the state Department of Natural Resources for oversight during the remediation, the release said. The work will cost $7.6 million, and WPS is being required to have financial assurance in that amount.
The former manufactured gas plant encompasses 15 acres, according to the court filing, and was operated by a predecessor before WPS took over the site. Cleanup will also be required for groundwater, soil and sediment nearby that are contaminated with PAHs.
According to the CDC, PAHs are a confirmed human carcinogen, affecting the liver. PAHs are a group of more than 100 different chemicals that are formed during the incomplete burning of oil, gas, garbage or other organic substances like tobacco or charred meat, the CDC site says.
The contamination produced at the WPS site was partially what drove the lower Menominee River to be listed as an Area of Concern by the Environmental Protection Agency in the 1980s. The WPS factory operated from 1910 to 1960 and created coal tar as a byproduct, which contains contaminants such as sulfur, heavy metals and metalloids such as mercury and arsenic.
Also contributing to the historical contamination of the river were the Tyco Fire Products facility, which tested PFAS-containing firefighting foam until 2017, and a company now known as Lloyd Flanders International, which produced woven wicker furniture and metal seating.
The lower Menominee River was delisted as an area of concern in August, after the EPA found that enough remediation had been done to begin the process of restoring native plants and animals. Though the area was delisted, it will still be tested every five years.
Laura Schulte can be reached at firstname.lastname@example.org and twitter.com/SchulteLaura.