Manistique River/Harbor Area of Concern
- Manistique, MI (Schoolcraft County)
- EPA ID# MID981192628
- CERCLIS listing
- Alias(es): N/A
Community Involvement Coordinator
Cheryl Allen (email@example.com)
312-353-6196 or 800-621-8431, ext. 36196
Remedial Project Manager
(where to view written records)
Manistique Public Library
100 North Cedar, Room 31
Schoolcraft County Court House, County Clerk,s Office
300 Walnut Street
Sampling of mud, surface water and fish conducted by U.S. Environmental Protection
Agency has shown that dredging of the Manistique Harbor and
River has been very effective in reducing PCB contamination. PCB is short for polychlorinated biphenyls, which are hazardous chemical compounds once used extensively in manufacturing. PCBs are no longer made in the United States but last a long time if released into the environment.
At the completion of dredging in 2000, the average PCB level in the shallow mud (sediment) was 7.7 parts per million. Parts per million or ppm is a scientific measurement meaning parts of PCBs per million parts sediment. After another round of sampling was done in 2004, the average PCB level had dropped below 1 ppm, greatly exceeding EPAs cleanup goal of 10 ppm. Scientists say these unexpectedly good results may be due to natural processes in the river and harbor burying the PCBs left over from the dredging.
In addition to the good news about the sediment, results of surface water sampling done in August 2004 showed PCBs were not detected, and none of the 29 fish sampled contained PCBs above the Food and Drug Administration limit of 2 ppm (the limit set to protect human health). Before dredging occurred in the Manistique River and Harbor, the average PCB level in walleye fillets from the river south of the highway bridge was 0.34 ppm. EPA predicted the dredging project would reduce the PCB level in walleye to 0.12 ppm, but the actual results showed PCB concentrations had dropped all the way to 0.056 ppm. Annual sampling will continue through 2008, when EPA Region 5 should have a better idea as to when the PCBs will no longer be a concern for the Manistique River and Harbor.
You will need the free Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.
- PCB levels decline at U.P.'s Manistique Harbor, News Release, April 06, 2006.
- Sampling Results Show Cleanup is Working (PDF) (2pp, 133K) March 2006 fact sheet
- U.S. EPA Continues Dredging Activities at the Manistique River and Harbor Site (PDF) (2pp, 395K) August 1998 fact sheet
- U.S. EPA Proposes Changes to Cleanup Work (PDF) (4pp, 51K) March 1996 fact sheet