Dredge tainted sludge in Thunder Bay harbour, report says

A new report recommends sediment, contaminated with mercury, should be dredged from Thunder Bay's harbour and taken to a confined disposal facility at Mission Island.

Final report on managing mercury-contaminated waste material now available for public input

A thick layer of pulpy, fibrous material like this sample above is suspended in the water at the Thunder Bay North Harbour site. (Jamie Saunders/EcoSuperior)

A new report recommends mercury-laced sediment should be dredged from Thunder Bay's harbour and taken to a confined disposal facility.

"The studies done on the sediment say that there is some ecological and human health risk in terms of leaving the mercury contamination in place," said Ellen Mortfield, executive director of EcoSuperior, the organization co-ordinating the investigation into how to deal with the submerged wood waste from a former paper mill on the city's waterfront.

Ellen Mortfield is the executive director of EcoSuperior, the organization co-ordinating the investigation in contaminated sediment in the Thunder Bay harbour. (Rotary Club of Thunder Bay, Port Arthur)

The recommendation from Cole Engineering Group Ltd. of Markham, Ont., is to dredge the sediment, put it on barges, and move it to an existing confined disposal facility at Mission Island. The estimated cost of the job is $44.4 million.

"We're talking about 22-hectares of the lakefront — the underwater portion — and there's up to 400,000 cubic metres of contaminated sediment," Mortfield continued.

"It's not like dirt on the bottom. It's layers and layers of thick, pulpy, mushy material. It's up to four-metres thick in places." 

Mortfield said EcoSuperior is looking for public input on the proposal.

The full report can be found on the EcoSuperior website. The organization is also planning an open house on the issue, for later this fall. 


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