Randle Reef: Hamilton Harbour Area of Concern

Located in the southwest corner of Hamilton Harbour on Lake Ontario, Randle Reef is the largest contaminated sediment site on the Canadian side of the Great Lakes. About 60 hectares in total, it contains about 695,000 cubic meters of PAH (polycyclic aromatic hydrocarbons) contaminated sediment - enough to fill a hockey rink nearly three times over. These carcinogenic toxins are the result of years of industrial pollution from multiple sources dating back to the 1800s.

Canada-United States Great Lakes Water Quality Agreement

In 1987, Canada and the United States identified 43 areas with high levels of environmental harm - 12 were Canadian and 5 were shared bi-nationally. The 2012 Great Lakes Water Quality Agreement reaffirms both countries’ commitments to restoring water quality and ecosystem health in Great Lakes Areas of Concern.

Remediation of Randle Reef

In 2015, a $138.9 million project to clean up the reef began. It is estimated the project will generate approximately $165M in economic benefits for the local community, create good middle class jobs, grow business development, and generate tourism.

The completed project is also a key step in removing Hamilton Harbour from the list of Great Lakes Areas of Concern.

This 3-stage project is lead by Environment and Climate Change Canada and is unique for its funding approach:

Stage 1: Construction of an in-water, double-walled engineered containment facility (ECF) over the most contaminated sediment in the harbour. This structure consists of 3400 23-33-metre steel beams inserted into the harbour floor.

Stage 2: Currently underway, the remaining contaminated sediment surrounding the ECF is being dredged from the harbour and placed into the structure. Upon completion,  over 98% of the contaminated sediment will be safely contained within the structure.

Stage 3: The final phase, expected to be completed by 2023, will involve capping the structure and transferring responsibility for it to the Hamilton Oshawa Port Authority to create additional land for the port.

Community involvement

Throughout the years of consultations and planning, community members and stakeholders have been integral to cleaning up Randle Reef. In addition to bringing together all three levels of government, industry and community, the project brings together a dedicated multi-disciplinary team of experts ranging from engineers to scientists, project managers to meteorologists.

This approach of managing contaminated sediment in an engineered facility and creating a port facility is a first in Canada. The project also ranked third on the Project Management Institute’s list of the top 10 influential projects in Canada for 2020.

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