The Sheboygan Harbor and River Superfund site stretches along the lower 14 miles of the Sheboygan River, running from a dam in Sheboygan Falls downstream to Lake Michigan. It passes through Sheboygan Falls, Kohler, and Sheboygan. The site was added to the National Priorities List (NPL) in 1986, which is the federal government's roster of the most serious contaminated sites in the country.
The main contamination concern is polychlorinated biphenyls (PCBs), a group of industrial chemicals linked to serious health effects. The former Tecumseh Products Co. plant in Sheboygan Falls is the primary source. PCBs have been detected in fish, wildlife, surface water, sediment, and floodplain soil since 1977. Beyond PCBs, EPA has identified eight metals at the site: arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc. These contaminants are found in sediment and surface water.
The main cleanup involved dredging more than 86,000 cubic yards of contaminated sediment from the river and inner harbor. Workers dewatered that material and sent it to a licensed landfill. Cleanup crews also removed PCB-contaminated soil and installed a groundwater intercept trench at the former Tecumseh facility. Construction finished in January 2013. The responsible party continues to monitor the river's recovery, and operation and maintenance work has been ongoing since then.
Despite that progress, the Fourth Five-Year Review, completed on July 28, 2025, found that the site remedy is not currently protective of human health and the environment. Previously unknown PCB and other contamination was found at the Tecumseh Source Area in 2016 and 2018, opening new exposure pathways. PCB levels in fish tissue and sediment continue to exceed cleanup targets set in the 2000 Record of Decision. Human exposure is not yet under control, though contaminated groundwater migration has been stabilized. Ongoing work includes further investigation at the Tecumseh Source Area, assessment of risks, and enhanced fish consumption advisories. A removal action is estimated to take place between December 2026 and February 2028. The site remains on the NPL and has not yet achieved sitewide readiness for anticipated reuse.
Community members can get involved by reaching out directly to EPA staff. Amelia Holcomb is the Community Involvement Coordinator and can answer questions about public engagement. Joseph Kelly is the Remedial Project Manager and handles questions about the technical cleanup work. Public records related to the site are available at the Mead Public Library at 710 North 8th Street in Sheboygan.
