http://www.pca.state.mn.us/

tinyURL : foyp8e2 | ID : 741Home   >   Water   >   Monitoring and Reporting   >   Contaminated Sediments

main content

Contaminated Sediment Studies: St. Louis River Area of Concern

The St. Louis River is the second largest tributary to Lake Superior. The lower estuary culminates in the Duluth-Superior Harbor, which is one of the more heavily used ports on the Great Lakes. In 1987, concerns over environmental quality conditions prompted the designation of the lower St. Louis River as one of 43 Great Lakes Areas of Concern (AOCs). This includes the segment from Cloquet, Minnesota to Lake Superior.

Due to sediment contamination, the St. Louis River AOC has several impaired uses, including degradation of bottom-feeding invertebrate communities, increased incidence of fish tumors and other abnormalities, fish consumption advisories, and restrictions on dredging. Some sediment-derived contaminants also appear to be carried by the water column to Lake Superior, the most pristine Great Lake.

photo of washing a sediment sampleThe St. Louis River Remedial Action Plan (RAP) progress report provides a three-phase sediment strategy to reduce impairments associated with sediment contamination. This strategy consists of (1) assessment studies to locate sediment hot spots (i.e., areas of elevated contamination), (2) development of hot spot management plans, and (3) implementation of remediation (cleanup) actions.

Since 1992, the MPCA and its collaborators have conducted several sediment investigations to implement the RAP sediment strategy. These projects have been conducted with the cooperation and financial assistance of either the U.S. Environmental Protection Agency (EPA) or its Great Lakes National Program Office. In addition, the Wisconsin Department of Natural Resources, Fond du Lac Band, U.S. Army Corps of Engineers, and others have conducted their own sediment studies in portions of the St. Louis River AOC. Most of these sediment quality data have been included in Phases I through IV of a GIS-based sediment quality database for the St. Louis River AOC.

The MPCA's Duluth office completed a preliminary sediment quality management plan for the St. Louis River AOC. For further information about refinements to this plan, contact Marc Hershfield at 218-302-6633.

The nonprofit St. Louis River Alliance is a key partner in the RAP process. Their Sediment Contamination Work Group is charged with providing scientific and technical advice on contaminated sediment issues. For more information, access these Web sites:

Final delisting targets were established in December 2008 for 9 beneficial use impairments. The draft delisting targets were developed through a stakeholder input process facilitated by the St. Louis River CAC, with final delisting targets established by the MPCA and Wisconsin Department of Natural Resources. For further information, contact Marc Hershfield at 218-302-6633.

A Superior Port Land Use plan was completed in June 2003 by the Duluth-Superior Metropolitan Interstate Committee. This plan includes several sections related to contaminated sediments and the management of dredged materials. An analogous Duluth Port Land Use plan was finalized in October 2005. A management plan for the Erie Pier Confined Disposal Facility was completed in 2007.

The Harbor Technical Advisory Committee (HTAC) is one of two advisory committees to the Metropolitan Interstate Council. The HTAC meets quarterly and brings together a large group of stakeholders to discuss and formulate recommendations addressing issues relevant to the Duluth-Superior Harbor, such as dredged material management. For more information about HTAC, access their Web site at:

A number of streams drain into the St. Louis River AOC. The City of Duluth, the University of Minnesota - Duluth, and their collaborators have assembled a Web site on Duluth's urban streams. The primary goals of this Web site are to enhance public understanding of aquatic ecosystems, to describe the influence of land uses in the watershed on these streams, and to illustrate the importance of these streams to both economic and environmental sustainability.

Information on surface water quality conditions in the St. Louis River AOC can be obtained from the MPCA's Environmental Data Access.

A list of the MPCA's contaminated sediment investigations is below. Assessment and hot spot management-type projects are listed in chronological order from when the grants were received. Unless otherwise noted, contact Judy Crane at 651-757-2293 or judy.crane@state.mn.us for more information about these studies.

Phase 1 - Assessment Studies:

Phase II - Hot Spot Management Plans:

Phase III - Remediation Projects:

  • PDF Document Minnesota Slip Feasibility Study. For more information, contact Susan Johnson at 218-725-7762.
  • Interlake/Duluth Tar Superfund Site. For more information, contact Susan Johnson at 218-725-7762.
    • Health Consultation. Sediment Operable Unit. St. Louis River/Interlake/Duluth Tar National Priority List (Superfund Site), St. Louis, St. Louis County, Minnesota (Minnesota Department of Health Under a Cooperative Agreement with the Agency for Toxic Substances and Disease Registry).
  • U.S. Steel Superfund Site. For more information, contact Susan Johnson at 218-725-7762.
    • Health Consultation. Technical Review of Discrepancies in 2002 Laser Induced Fluorescence Data, and 2003 and 2004 Analytical Data. St. Louis River Sediments: U.S. Steel Site, Duluth, St. Louis County, Minnesota (Minnesota Department of Health Under a Cooperative Agreement with the Agency for Toxic Substances and Disease Registry).
Last modified on February 21, 2012 15:47
back to top