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Case Summary: Removal of contaminated sediments to foster redevelopment of Michigan Lakefront and Marina

Under a consent decree approved March 1, 2017, Northern States Power Company (d/b/a Xcel Energy) agreed to dredge contaminated sediments in Chequamegon Bay in Lake Superior. The bay is adjacent to the Ashland/Northern States Power Lakefront site. The 2017 consent decree requires Xcel Energy to remove all contaminated sediments in the bay to meet the cleanup goals and performance standards established by the U.S. Environmental Protection Agency (EPA) and Wisconsin’s Department of Natural Resources (WDNR). The cleanup work constitutes Phase II of the site cleanup work and is expected to be completed in 2018 at an estimated cost of $42 million.

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Information about Xcel Energy

Headquartered in Minneapolis, Minnesota, Xcel Energy’s operations include the activity of four wholly-owned utility subsidiaries that serve electric and natural gas customers in eight states. These utility subsidiaries, referred to as operating companies, are Northern States Power Company-Minnesota, Northern States Power Company-Wisconsin, Public Service Company of Colorado and Southwestern Public Service Company. A predecessor entity of Xcel Energy owned and operated a manufactured gas plant on a portion of the Site from which hazardous substances were released to a city-owned park and Chequamegon Bay.

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Information about Ashland/Northern States Power Lakefront Site

The Ashland/Northern States Power Lakefront Superfund site includes a former manufactured gas plant owned by Xcel Energy, a city-owned park, and approximately 16 acres of contaminated sediments in Chequamegon Bay, which is part of Lake Superior. Soil, groundwater, and sediments at the site were contaminated by coal tars from the gas plant that contain polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs).

More information about the site is available from the Ashland/Northern States Power Lakefront site profile page.

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Summary of the Consent Decree

A consent decree approved in 2012 between EPA, the WDNR, and Xcel Energy addressed contaminated soil and groundwater within the on-land areas of the Site (Phase I Work). The Phase I Work is now complete except for the ongoing pump and treat of contaminated groundwater and a cover over the park to be constructed after completion of the final sediment cleanup.

The March 1, 2017, consent decree requires Xcel Energy to remove all contaminated sediments in the Bay to meet the cleanup goals and performance standards established by EPA and WDNR (Phase II Work). The Phase II Work is the final remedial action for the Site and is expected to be completed in 2018. EPA agreed to bifurcate the work into two separate settlements so that Phase I work could proceed while EPA and Xcel Energy worked on resolving technical differences on the sediment remedy.

The 2017 consent decree for Phase II Work represents an agreed upon cleanup approach utilizing adaptive management processes to facilitate in-field decision making to achieve the cleanup goals. In addition to removing contaminated sediment, the cleanup features a permanent breakwater within Chequamegon Bay that was constructed by Xcel Energy with input from the city of Ashland. The breakwater attenuates waves within the Site to facilitate dredge operations. The breakwater will remain after the cleanup is complete and will be utilized by the city to protect a new marina and enhance its waterfront redevelopment plans.

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Contact Information

For more information, contact

Barbara Gutierrez
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Washington, DC 20460

Craig Melodia
Associate Regional Counsel
U.S. Environmental Protection Agency
Region 5
77 W. Jackson Blvd.
Chicago, IL 60604-3590
(312) 353-8870

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