Pollution containment efforts move to Slips 3, C in Duluth harbor
Following efforts to cap contaminated sediments in Minnesota Slip, the Minnesota Pollution Control Agency on Monday asked for public comments on sediment-capping efforts planned for Slip 3 and Slip C in the Duluth harbor.
Comments will be accepted through April 4 on the two projects expected to cost $4.5 million combined.
Slip 3 is just west of the Pier B hotel development and just east of the CRH U.S. cement unloading and storage site, and is where the retired Coast Guard Cutter Sundew has been docked in recent years.
Slip C is just west of there, running parallel to shore in front of the former Georgia-Pacific board plant which currently serves as a hub for Jeff Foster Trucking.
Contaminants in the slips — including high levels of lead, cadmium, copper, mercury, nickel, zinc, dioxin, polychlorinated biphenyls and polyaromatic hydrocarbons — will be capped with dredged material from "clean" areas of the harbor. There are more than 116,000 cubic yards of contaminated sediment that ranges from 2.5 to 6 feet thick below the water.
The PCA says the newly created cap "will be beneficial to sediment-dwelling and aquatic creatures, as well as the fish community, while effectively isolating the contaminants from possible release to the harbor, the St. Louis River and Lake Superior."
Work is expected to begin in both slips in September and last through December, at some points on a 24/7 basis.
The pollution, which is common along the waterfront, came from a century of heavy industrial use when, before the Clean Water Act, waste materials were often disposed of by dumping them in the harbor.
The slips are among 10 projects identified to clean up the entire Twin Ports harbor and lower St. Louis River estuary. State and federal permits and authorizations are still required for the cleanup which is being paid for from a 35/65 match between state bonding dollars and the U.S. Environmental Protection Agency's Great Lakes Legacy Act.
Environmental assessment worksheets for the two projects are available at pca.state.mn.us or by calling Patrice Jensen at (651) 757-2465. Written comments specifying the cleanup site may be sent by email at email@example.com or mailed to Jensen's attention at the MPCA, 520 Lafayette Road N., St. Paul, MN 55155.