Decades-long Manistique River cleanup nears end
MANISTIQUE — Work on the final stage of a project intended to remove contaminated sediments from the Manistique River and eventually get the river delisted as a Great Lakes Area of Concern has been ongoing this summer. The project will continue into the fall.
The project’s manager, Samuel Noffke of Michigan’s Department of Environment, Great Lakes, and Energy (EGLE), said the Manistique River has been considered an area of concern for decades due to its elevated polychlorinated biphenyl (PCB) levels. The presence of PCB in the river was said to be related to the use of chemicals to “de-ink” recycled paper at the city’s paper mill in the past.
The river was named an area of concern due to the beneficial use impairments that were placed on it. Most of these impairments have since been removed, but restrictions on fish consumption and navigational dredging remain.
While the current dredging project began in 2016, efforts to remove contaminated materials from the river have been ongoing for quite some time.
“They’ve been dredging this thing for … a couple decades, easily,” Noffke said.
The final stage of the current project — expected to be the last major project required before the river’s area of concern status can potentially be removed — is focused on Manistique’s lower harbor. The project contractor is White Lake Dock & Dredge, which was involved with local dredging efforts in 2016.
According to Noffke, the first stage of dredging in the lower harbor is complete.
“Now they have to go back and they have to sample … (some of) the areas they have dredged,” he said.
The sampling will be done by Arcadis, the project’s engineering contractor. If these samples find remaining PCB contamination, White Lake will re-dredge any affected areas.
Noffke said EGLE anticipates any necessary re-dredging will take place in the next few weeks. However, the timeline for the project is “up in the air” right now.
“We are ahead of schedule — our original timeline doesn’t really work for us at the moment,” he said.
Noffke noted this means the project has an increased chance of being completed before its original deadline, which he said was in early December.
Later, another round of sampling is set to take place. Information from these samples will be used by White Lake to determine the locations in the project area that need to be covered with an activated carbon-sand cover.
“Anything that’s left will be locked up with that carbon,” Noffke said.
He did not expect material needed for the covers to arrive in Manistique until Monday, Sept. 16 at the earliest.
Once covers have been placed in the lower harbor, White Lake will move on to placing covers in backwater areas north and south of U.S. 2. Dredging work took place in these areas in 2016.
After this work is done, White Lake will reconstruct shoreline areas affected by the project and do other work to restore the areas to their previous state.
“They will have time this fall to go back in and restore the site to what it was prior,” Noffke said.
Next spring, White Lake will ensure soil erosion controls are in place and reseeding efforts have begun on the shore and throughout the staging area for the project.