Lake Ontario ‘aquatic landfill’ to contain 150-year-old toxic blob from industrial pollution

A federal government scientist named Tom Murphy was out on his boat on Lake Ontario in 1988, taking samples of lakebed sediment, when he pulled up a scoop of oozing black goo. 

His upper lip went numb. 

He detected the pungent, sour smell of mothballs — naphthalene, a carcinogen produced in coal tar distillation. “We quickly could smell that there were a lot of volatile compounds,” Murphy says.

Murphy was sampling in Randle Reef, which along with Hamilton Harbour around it had been listed among 43 “areas of concern” for pollution in the Great Lakes in 1985, one of the 12 wholly located in Canada.

Murphy had found the toxic site’s oozing epicentre.

The humongous blob of coal tar had already been releasing contaminants on the bottom of Lake Ontario for decades in the inner harbour next to one of Hamilton’s oldest steel mills.

Coal tar is a by-product of coal gasification — a viscous, sooty reminder of the industries that have been operating here for more than a century. 

Randle Reef is now considered the largest contaminated site on the Canadian side of the Great Lakes and the second-most contaminated site in Canada after the Sydney Tar Ponds in Nova Scotia. The volume of contaminated sediment in the Hamilton Harbour could fill up three hockey arenas. 

The 60-hectare blob at Randle Reef is a so-called “spill in slow motion,” releasing cancer-causing chemicals into the water and creating an ecological dead zone.

But a solution is in the works.

More than 30 years have passed since the toxic site was formally identified but it took until 2016 for Environment and Climate Change Canada, along with other groups at the table, to put a plan in motion to deal with it.

Rather than remove the blob of black sludge, the $139-million plan is to build a box around it. 

And the Steeltown solution to the Steeltown problem? Make that box out of steel.

The Stelco steel mill in Hamilton, Ontario. Photo: Russ Heinl / Shutterstock

‘Not a perfect solution’

After decades of hand-wringing, roundtables, changes in governments, ballooning cost estimates and steel company bankruptcies, the containment box was widely considered the only feasible solution with the money available.

The structure will cover more than six hectares of the southwest corner of Hamilton Harbour and is being built in the water, with a cap above the surface that will connect to the shoreline. 

But some wonder if the unprecedented plan to build a box around this massive contaminated site is the right move.

“It is not a perfect solution,” says Gail Krantzberg, an engineering and public policy professor at McMaster University in Hamilton who has worked in Great Lakes policy for more than 30 years.

“We don’t have any really good solutions for severely contaminated sediment other than burying it, really, because removing it brings all those other huge ramifications of moving it. How, and to where, at what cost and at what risk?”

Scientists think the blob started taking shape more than 150 years ago with runoff from a coal plant that used to stand at the shore.

A contentious question over the years has been the degree to which Stelco, a steel company with operations immediately next to the blob, has contributed to the mess. But despite kicking in $14 million worth of steel for the box, neither Stelco nor any other company has been willing to shoulder the blame for the blob.

The very industries that built Hamilton into a major city — and the ability to manufacture products, dump waste in the water and ship goods out via the Great Lakes — have jeopardized the safety and health of its residents, many of whom wouldn’t dream of jumping in the lake for a swim.

Fish and wildlife that call the harbour home have developed tumours and reproductive deformities, and habitats have been destroyed. 

“It took a long time to wreck the place. It’ll take a long time to fix it,” says Chris McLaughlin, head of the Bay Area Restoration Council, a non-profit that formed to reconsider Lake Ontario as a dumping ground for wastewater and industry. 

In 2016, mechanical dredging was conducted between the double walls of the engineering containment facility in the Hamilton Harbour. The box structure encloses just over six hectares of the most contaminated sediment in Randle Reef. The contaminated sediment trapped between the walls was also placed inside the facility. Photo: Environment and Climate Change Canada

‘We’re creating an aquatic landfill for toxic material’

For a while, the plan in the late 1990s was to dig up all of the sediment and burn it in Stelco’s sintering plant. But the workers who would have been responsible for the burning worried about health impacts of dioxins released in the air, and the plan was scrapped.

The sediment at the Randle Reef site is contaminated with polycyclic aromatic hydrocarbons and heavy metals. Even the addition of hydrocarbon-eating microorganisms into the water, which naturally helped along BP’s Gulf of Mexico oil spill clean-up, couldn’t break down the persistent compounds.

“It was so heavily contaminated that bacteria didn’t even want to eat it,” Krantzberg says.

That persistence and volatility would eventually thwart any ideas to actually clean up and remove the blob.

Over the years, hundreds of articles in the local newspaper, The Hamilton Spectator, covered roundtable after roundtable convened in search of a solution for Randle Reef and enough money to pay for it. Governments, industry and community groups had seats at that table, and it wasn’t easy to reach a consensus. Funding was even further out of hand.

But it was clear something had to happen. 

“The longer we have these conversations about how to remove this stuff, the longer that blob, which is quite expansive, is sitting there and getting resuspended and contaminants are moving around the harbour,” Lynda Lukasik, founder of Environment Hamilton, says of those meetings over the years. “So there’s an urgency.”

The box taking shape at Randle Reef in July 2016. Photo: Birmingham Foundation

Once the idea to box the sediment in place gathered support, opposition arose from environmental advocates who worried about creating yet another parcel of land on what used to be water. Much of the Hamilton Harbour shoreline has been artificially created to support industry, eliminating swaths of wetlands and wildlife habitat. 

When Krantzberg was working for Ontario’s environment ministry, she stepped away from the decision-making process because she thought it wasn’t moving fast enough. While she’s glad to see something being done now, she is a reluctant proponent of the plan to box the blob. “I would like to see it either treated in place [or] capped underwater — not turned into a piece of land,” she says. 

Another person who wasn’t fully on board with the box solution was Lukasik, who sat at the many roundtables as a representative of Great Lakes United, a consortium of Canadian and American environmental groups. She says it isn’t “a final enough solution.” 

“I would argue to people, it’s kind of like we’re creating an aquatic landfill for toxic material,” she says. She still has questions. 

Lukasik hoped, at least, that the box would have a green roof — something that’s easily removed should more advanced technology come along in a decade or two to treat the sediment it contains. That doesn’t appear to be in the plans for the landform that will instead provide a foundation for new port authority buildings.

But Lukasik admits she is relieved something is being done about the blob.

A plan in a box

In 2016, to much fanfare, the box plan officially took shape. While the contaminated area extended over 60 hectares of lakebed, the box itself covers 6.2 hectares of the most toxic sediment — or about six city blocks. 

Crews started by building a double-walled and lined box that drives down 24 metres into the lakebed, before dredging more contaminated sediment from around the site and funnelling it through a pipeline into the box. That dredging is about half complete and crews are at it again as work restrictions due to the COVID-19 pandemic have been lifted.

Eventually the sediment inside the box will be compressed, the excess water treated and drained, and the box capped and sealed to keep the sediment from the rest of the lake water.

An aerial photo from summer 2019 showing the extent of the containment facility, the hydraulic dredge and its pipeline connected to the water treatment plant on shore. The plant treats water that’s been displaced within the structure as sediment is pumped in, so it can be released into the harbour. Photo: Environment and Climate Change Canada

One-third of the $138.9-million bill is being paid by the federal government, one-third by the province and the final chunk comes from the cities of Hamilton and Burlington, the Halton Region, the Hamilton-Oshawa Port Authority and Stelco. 

The project is expected to wrap up by 2022, and the steel box — officially called an engineering containment unit — is built to have a 200-year life span. The port authority has assumed responsibility for maintaining and monitoring the structure once a 15-year Environment Canada monitoring period passes. Ostensibly, the port can offset any maintenance costs by leasing the new “land.” 

Now other cities facing big pollution clean-ups are taking cues from Hamilton’s progress to solve their own environmental disasters. Roger Santiago, head of Environment Canada’s sediment remediation group, says a Randle Reef-type approach is on the short list for cleaning up a contaminated site in Thunder Bay. 

In the Hamilton Harbour, knocking out the blight at Randle Reef could greatly improve the reputation of these waters, and the health of the animals and environment. “It’s recognized that the successful completion of the Randle Reef project will go a long way towards delisting this area of concern,” says Santiago. 

Everyone’s problem, no one’s responsibility

About a decade ago, after completing her master’s degree in civil engineering at the University of Toronto, Zobia Jawed was working on a contract with McMaster University and oilsands producer Syncrude to investigate remediation solutions for Alberta’s tailings ponds.

At the time, she mentioned her area of study to an environmentalist, who asked: “Why are you working for the oilsands when we have an ‘oilsands’ right here?” 

Intrigued, she made her way down to the harbour and saw where the outline of the blob was roughly marked with white buoys. That set Jawed’s course for a PhD looking at the complicated 30 years it took to come to this solution for Randle Reef. Her aim was to expedite decision-making for other communities facing “wicked” pollution troubles. Now she’s helping landowners and local governments around Lake Erie confront a toxic algal bloom with a process she developed after studying Randle Reef. 

Among the biggest problems she found in the Hamilton Harbour conundrum was a leadership vacuum in who takes responsibility for legacy contamination. And she’s finding parallels in contaminated water projects across Canada. “If the water is clean, everyone owns it,” Jawed says. “But if it’s contaminated, who wants this contamination?”