Nova Scotia

This company wants to take Boat Harbour's polluted sludge and turn it into roads

A Nova Scotia company says it could turn hundreds of millions of litres of polluted sludge from Boat Harbour into a non-toxic construction material, offering an alternative to the current plan to permanently store the dredged sludge in a massive tank on site.

Proposal offers alternative to storing contaminated waste in a giant tank

Aerators churn up toxic mill waste at Boat Harbour before it was decommissioned as an effluent treatment facility in January 2020. (Steve Lawrence/CBC)

A Nova Scotia company says it could turn hundreds of millions of litres of polluted sludge from Boat Harbour into a non-toxic construction material, offering an alternative to the current plan to permanently store the dredged sediment in a massive tank on site.

Boat Harbour was once a tidal estuary, but for more than 50 years it acted as a receptacle for industrial waste from the nearby and now shuttered Abercrombie, N.S., pulp and paper mill currently owned by Northern Pulp.

The provincial government had previously committed to cleaning up waste from Boat Harbour that predated the current ownership, but recently took responsibility for Northern Pulp's portion of the job after the company repeatedly failed to submit a plan.

In total, Crown corporation Nova Scotia Lands estimates there will be between 312 million and 517 million litres of sludge to dredge up and manage.

Nova Waste Solutions wants all of it.

"Our alternative solution is an affordable and certainly a socially responsible solution, and then probably the best environmental solution," CEO Stephen Mader said in an interview.

Mader wouldn't say how much the process would cost, except that it's the most affordable way to deal with toxic waste, "if not in the near term, absolutely for the future."

"Once we've processed the toxic and hazardous material, there's nothing left but a glassy rock substance that's inert and safe to be used for road construction," he said.

This waste processing facility in France uses the same plasma furnace system that Nova Waste Solutions wants to build in Nova Scotia. (Submitted by Nova Waste Solutions)

But first, the company has to build the processing facility. Before it can do that, it will need government approval. 

Nova Waste Solutions has not yet registered for a provincial environmental assessment — a process that can take years to complete. Mader said the company has been in talks with environment department officials and is preparing to make a submission.

Toxic waste melted, neutralized by special furnace

Gord Helm, Nova Waste Solution's senior vice-president of technology and chief technical officer, said the Boat Harbour cleanup isn't the only job the company wants to clinch.

The proposed facility could take all kinds of waste that would typically end up in a landfill, Helm said, dry it and then melt it in a plasma furnace, turning the waste into "molten slag." As it cools, the material hardens and can be broken up, then recycled for civil construction projects.

Melted and neutralized waste flows out of a plasma furnace. Once cool, it will be a glassy, rock-like material than can be broken up and recycled into construction material. (Submitted by Nova Waste Solutions)

The neutralizing step is called plasma vitrification and it isn't a new process — Helm said facilities in Europe have been doing it for decades — but it would be new to Nova Scotia. 

'Exponentially a better option,' company says

Nova Scotia Lands' current plan would see the waste from Boat Harbour stored in a 6.7-hectare tank that sits next to the polluted lagoon. The tank, also known as a containment cell, was built in 1995 and already contains millions of litres of waste material from the mill's operations.

The tank would have to expand upward by 12 to 20 metres to accommodate the remediation waste. Once full, the tank would be capped and covered in soil and vegetation. According to a Nova Scotia Lands description of the project, some short shrubs "would tie the sludge disposal cell visually into the surrounding tree line."

But that wouldn't be the end of the story. The containment cell is expected to slowly and continuously generate leachate — water containing some of the contaminants from the sludge — that would have to be removed and trucked away for disposal. 

The Northern Pulp mill in Abercrombie Point, N.S., is viewed from Pictou, N.S., Friday, Dec. 13, 2019. (Andrew Vaughan/The Canadian Press)

The whole remediation plan is currently under review by the Impact Assessment Agency of Canada

A spokesperson for Nova Scotia Lands said with the federal impact assessment underway, the Crown corporation would not provide comment on any process for remediating Boat Harbour outside the one already proposed.

Regardless of what the federal review may find, Helm said processing hazardous materials until they are inert is always "exponentially a better option" compared to long-term storage.

He said underground storage may be safe in the short term, but he expects long-term consequences for humans and the environment.

"We have to stop polluting the planet when we have options to do otherwise," said Helm.

Sludge storage not acceptable to some in Pictou Landing

Nova Scotia Lands has said the containment cell is a safe way to store the sludge, but many members of Pictou Landing First Nation, which is adjacent to Boat Harbour, share Helm's skepticism on that point and say it's not an acceptable solution.

This map shows the location of Northern Pulp, Boat Harbour and Pictou Landing First Nation. (Marine Pollution)

Concern about the containment cell was a dominant topic in Nova Scotia Lands' consultation with the Pictou Landing community in 2019, with some saying the plan perpetuates environmental racism.

Sean Fraser, the Liberal MP whose riding includes Pictou Landing First Nation, said if the community were to "formally register" its opposition to the containment cell, alternatives would have to be considered.

"Every aspect of the use of Boat Harbour as an effluent treatment facility from its inception has been an example of environmental racism," Fraser said in an interview.

If the community formally opposes the continued use of the containment cell and the current plan goes ahead anyway, "Yeah, I do think that would be a continuation of environmental racism," said Fraser.

The band is expected to soon file a submission with the Impact Assessment Agency of Canada, which will eventually be made public. Pictou Landing Chief Andrea Paul did not respond to CBC's requests for an interview.

Mader and Helm said they briefed Paul on their proposal last week.

They said they've requested a meeting with Premier Iain Rankin to brief him on their proposal, too.


Taryn Grant


Taryn Grant is a Halifax-based reporter and web writer for CBC Nova Scotia. You can email her with tips and feedback at