Governments collaborate to keep chemicals out of St. Lawrence River

The three levels of government have teamed up on a multimillion-dollar plan to stop the leakage of chemicals from land along the Bonaventure Expressway into the St. Lawrence River.

"It's also one of the most complicated and big environmental sites in Canada, it's one of the biggest," said Martin Chiasson, an engineer overseeing the project. 

"[I am] very proud today to say that we are finally able to put forth a concrete solution."

Starting in 1866 the site was a CN rail yard and a landfill for industrial and domestic waste. It was later filled to create a parking lot for Expo 67, and later the Technoparc.

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About 25 years ago, the leftover fuel and chemicals from the site started leaking into the groundwater below the site, which then flowed into the St. Lawrence.

PCBs in the east

Pollutants in the groundwater can differ depending on where it comes from.

Diesel fuel contaminated with polychlorinated biphenyls, or PCBs, floats on the water in the east sector of the expressway between the Clément and Victoria bridges.

The solution will be a retaining wall to collect the diesel before it gets into the river. The PCB-laced diesel will be transported to a dumping site approved by the province.

Ottawa will provide $12 million for Project Bonaventure.

PAHs in the west

The western portion of the affected site includes the land along the expressway facing Nuns' Island at the approach of the Champlain Bridge.

Tests on groundwater there revealed the presence of ammonia nitrogen, polycyclic aromatic hydrocarbons (PAHs), and dissolved metals.

In that sector, a hydraulic barrier and series of wells will be built along the shore. The system will pump contaminated water through a treatment system, where it will be cleaned, tested and discharged back into the river. It will cost $15 million, split between Ottawa and Quebec.

Montreal will build another wall and treatment plant near the Technoparc. That plan is still in the planning stages and will cost $77 million over 25 years, said Réal Ménard, who is in charge of sustainable development for the city.

He expects Quebec will help cover those costs.

A need for oversight

Environmentalist and deputy Green Party Leader Daniel Green isn't impressed by the plan.

He says despite promises to deal with the site, the city has been "derelict" in cleaning up the site and the federal and provincial governments have left the city alone.

He wants independent oversight of the operation to ensure it's being cleaned up properly.

"Because the government is the polluter, who is going to keep an eye on the government?" he said.

He says the chemicals in the groundwater can be volatile and produce a lot of fumes. Pumping them out of the water may actually create air pollution, yet another reason, he says, why the government should be held to account by an independent group.

The systems are expected to be built and running by 2017.