Site History

The Azcon/Duluth Seaway Port Authority (DSPA) Slip is a manmade slip in the Duluth-Superior Harbor. The area is rich with a history in manufacturing and commercial shipping of steel, appliances, and heavy machinery, as well as logging and ship building. Before modern-day environmental regulations, common practices led to a buildup of contamination in the sediment. This resulted in damage to the underwater habitat and negative impacts to the food chain. 

​​The Azcon/DSPA Slip in the St. Louis River Area of Concern. Investigations reveal that the sediment is contaminated with a suite of heavy metals and chemicals, including dioxins/furans and PAHs. The contaminants are primarily located along the northern dock wall and the head of the slip. A voluntary, public-private partnership has formed under the Great Lakes Legacy Act to address contamination. A project agreement for cleanup has been signed, and a cleanup will likely take place tentatively in 2020. Because the slip is still active, the remedy has been designed with boat traffic in mind. 

Schedule

​The project design is complete and a cleanup is slated to take place  tentatively in 2020.

Location

The Azcon/DSPA Slip is an approximately 6.4-acre slip located on Rice's Point in the northwestern portion of the harbor in Duluth, MN. The slip is within the St. Louis River Area of Concern. This slip is adjacent to Azcon Metals and Duluth Lake Port Storage. 

Figure 5 from the Focused Feasibility Study performed by Minnesota Pollution Control Agency shows how the project team determines the remedial footprint, or cleanup area, with consideration of sediment quality data.

Cleanup Process

​Sediment to be remediated: 55,000 cubic yards
Contaminants: Metals, Dioxins/furans, PAHs 
Method: Capping
When: 2020
Partners: U. S. Environmental Protection Agency and Minnesota Pollution Control Agency
Cost: $4.5 million
Note: The project includes removing 600 cubic yards of sediment before capping takes place.

A conceptual site model of the Azcon/DSPA Slip, Figure 6 from the focused feasibility study performed by Minnesota Pollution Control Agency

Short-term Disruptions

Sediment remediation is like a construction project on the water. It can involve large equipment, bright lights, and noise. Many projects even continue into the night and on weekends to speed up the process. Remediation can feel inconvenient, but a bit of patience results in a big payoff. 

Long-term Benefits

• Sediment remediation would prevent contamination from entering the food chain. Contaminants have negative impacts on the health of the ecosystem and contribute to fish consumption advisories on fish caught in the  St. Louis River estuary.
• Restoration improves habitat for fish and wildlife species, allowing local populations to increase and thrive.
• ​To learn more about the significant benefits enjoyed by communities in Great Lakes Areas of Concern after a cleanup, watch the Great Lakes Legacy Act video.

More Information

Documents

• St. Louis River Area of Concern remedial action plan update (PDF, 104p, 2.90MB) November 2019

Stakeholders

• St. Louis River Alliance
• ​City of Duluth
• Wisconsin and Minnesota Sea Grant St. Louis River - Stories and Science 
• Minnesota Pollution Control Agency
• Minnesota Department of Health Fish Consumption Guidance
• Wisconsin Department of Natural Resources Area of Concern
• U. S. Environmental Protection Agency