Michigan EGLE has announced a 28-day public comment period for the proposed removal of the Restrictions on Dredging Activities Beneficial Use Impairment (BUI) from the Manistique River Area of Concern ( AOC ).
The Manistique River was declared an AOC in the mid-1980s, consistent with the Great Lakes Water Quality Agreement between the United States and Canada. At the time, AOCs were some of the most heavily polluted sites impacting Great Lakes water quality.
Chemical contamination in the lower Manistique River primarily consisted of polychlorinated biphenyls (PCBs) discharged from wastewater lagoons, resulting from the de-inking of carbonless copy paper at a manufacturing facility adjacent to the river.
Since the early 1990s, several sediment removal projects have been implemented in the lower river and harbor, which removed tens of thousands of cubic yards of contaminated sediment, sawdust and related organic materials.
The final cleanup project was completed in 2019, with funding from the federal Great Lakes Restoration Initiative.
The project included removal of PCBs and the installation of six inches to one foot of clean sand mixed with granular activated carbon, to chemically bind any residual contaminants and provide a physical barrier to reduce the potential for any future biological uptake.
Findings from the most recent analyses indicate that sediments in the federally maintained navigation channel consist of over 94% clean sand, and that there are no special handling or disposal measures required for those materials due to chemical contamination.
Public review and comment is invited and will be accepted through September 8, 2021.