The Ashland/Northern States Power Lakefront site sits along Chequamegon Bay in Ashland, Wisconsin. It was placed on the National Priorities List (NPL) in September 2002, after being proposed in December 2000. The NPL is EPA's list of sites that need long-term cleanup. Industrial activity at the site, including a former manufactured gas plant, left behind tar, oil, metals, and organic compounds in soil, groundwater, sediment, surface water, air, and fish tissue. Two artesian wells were closed because of groundwater contamination. Access to parts of the bay and shoreline stays restricted because disturbing sediment can release oil and tar slicks that cause skin irritation and increased sun sensitivity.
EPA has identified more than 100 contaminants of concern at the site. These include metals such as arsenic, lead, mercury, cadmium, and chromium. Organic chemicals include benzene, toluene, ethylbenzene, and xylene. Polycyclic aromatic hydrocarbons (PAHs), naphthalene compounds, and fluoranthene are also present. Benzene shows up in soil, groundwater, sediment, and air. Several contaminants have accumulated in fish tissue, pointing to potential exposure pathways.
Cleanup was organized into two phases under Operable Unit 01, governed by a Record of Decision issued in September 2010. Phase 1, finished in 2016, removed contaminated soil from under the former gas plant and Kreher Park, covered the area with clean material, and installed barriers to contain groundwater. A breakwater barrier was built in 2015 to control wave action. Phase 2, completed in 2018, used wet dredging to remove contaminated sediment from 16 acres of Chequamegon Bay. A metal wall along the shoreline now contains and treats groundwater before it is discharged. Overall construction wrapped up in December 2019. Operation and maintenance for Operable Unit 01 began in May 2020 and continues today.
EPA has determined that human exposure is under control, groundwater migration is under control, physical construction is complete, and the site is ready for anticipated use. Fish in Chequamegon Bay do not contain levels of site-related chemicals that are a health concern, though general fish consumption advisories for Lake Superior still apply. Ashland's public water supply comes from Chequamegon Bay, outside the known contamination zone. Some nearby private wells are not currently contaminated but could become contaminated in the future. The most recent five-year review was completed in August 2024 and confirmed the remedy continues to protect human health and the environment. The site has not yet been deleted from the NPL.
Community members can view site documents at four locations: Vaughn Public Library in Ashland, the DNR Spooner Service Center in Spooner, Bad River Public Library in Odanah, and the Red Cliff EPA Office at the Fish Hatchery in Bayfield. Appointments at the Red Cliff location can be made by calling 715-779-3650, and at the Spooner location by calling 715-635-4049. EPA and Wisconsin Department of Natural Resources (DNR) staff are also available to answer questions directly.
