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Province cutting diesel particulate levels in underground mines

New regulations to reduce emissions by 70 per cent of current levels come into effect in September

Underground miners will breathe a little easier this fall with the arrival of new provincial regulations requiring better ventilation in the workplace.

Announced on April 11, the Ministry of Labour, Immigration, Training and Skills Development is introducing new legislation that lowers the acceptable level of diesel particulate that’s emitted by diesel-powered equipment underground.

Currently, Ontario permits levels of up to 400 micrograms per cubic metre of air — one of the highest allowable levels in the world.

But under the new legislation, that number would be cut by 70 per cent, to 120 micrograms per cubic metre of air, and companies in non-compliance will face orders and fines, among other measures.

“We know that long-term exposure to diesel exhaust while on the job can be a significant cause of bladder and lung cancer, and cardiovascular disease for miners,” said Labour Minister Monte McNaughton, who travelled to the NORCAT underground mine in Onaping, northwest of Sudbury, to make the announcement.

“Currently, Ontario has the highest diesel exposure limits in Canada. That is why we're introducing the toughest standards in North America to reduce exposure by 70 per cent and keep our miners safe.”

The changes come following a push by the United Steelworkers Local 6500, which represents about 2,700 mine workers in the Sudbury region.

Last fall, the union launched a public awareness campaign calling for acceptable diesel particulate exposures to be lowered to 20 micrograms per cubic metre of air, the level recommended by both the Carcinogen Exposure Canada (CAREX) and the Occupational Cancer Research Centre.

The new levels being introduced by the ministry are still higher than what the USW was seeking, but Nick Larochelle, Local 6500's president, lauded the announcement as a positive step forward.

“This is excellent news today,” he said. “The reduction of the occupational exposure limit by 70 per cent is an awesome start.

“We look forward to continuing working with the ministry to bring that number down to 20 micrograms per cubic metre of air.”

Offering an analogy for non-mine workers, Larochelle noted that on days when Environment Canada issues a smog advisory, people are advised to remain indoors when the smog reaches 50 parts per million.

By comparison, mine workers can be exposed to diesel particulate at 120 parts per million.

“So we're looking forward to the work that has to get done to bring that number down,” Larochelle said.

When asked, McNaughton would not say how the ministry arrived at the number it did, only that it would continue working with the Steelworkers to "continue to move the needle to improve health and safety for miners."

Compliance will be monitored by health and safety inspectors who will levy fines, issue orders, or potentially deliver stop-work orders for those companies that do not comply, he said.

“With labour, government and industry working together, we can improve health and safety,” McNaughton added. “It's great to see a number of companies stepping up and supporting this initiative because they want to get there, too, and with the new technologies, it's going to improve the health and safety of miners.”

Some of that new technology includes remote-operated robots, which can identify loose rocks, misfired explosives and other safety hazards while workers keep a safe distance. McNaughton said the legislative changes would also allow for this type of technology to be used.

But central to the industry's evolution are battery electric vehicles (BEVs), which many companies are already introducing to their underground fleets.

Mines Minister George Pirie, who joined McNaughton for the announcement, referenced his recent visit to Glencore's Craig Mine where the company is undertaking its new Onaping Depth project.

Located beneath Craig Mine, the $1.3-billion operation will descend 2.6 kilometres and employ all-electric technology. Production is expected to start in 2024.

Craig Mine is deep and it's hot, Pirie said, but the air is clean, thanks in large part to the use of BEVs underground.

“It's incredibly important to understand that it's the critical minerals that you mine right in this basin and throughout Northern Ontario that allow that to happen, to build the batteries that allow these vehicles to be driven with the electronic technology,” said the former mine executive.

“It's part of this critical minerals strategy that we've got which is to secure the supply chains to ensure that we can get everything right here in Northern Ontario and take our rightful position in the electronic revolution that's happening all across Northern Ontario.”

Worker advocate Janice Martell, who is a vocal proponent of occupational health and safety for mine workers, applauded the announcement, noting that “any movement towards safer places for workers to work is a good thing."

Martell is the engine behind the McIntyre Powder Project, a multi-year research and education project that brought to light the use of a finely ground aluminum dust called McIntyre Powder in underground mines between 1943 and 1980.

Thanks in large part to her work, last year the ministry announced that a diagnosis of Parkinson’s disease that has been linked to work-related exposure to McIntyre Powder would be recognized as an occupational disease under the Workplace Safety and Insurance Act.

That makes it easier for workers to receive compensation from the Workplace Safety and Insurance Board.

Martell noted that not all mines have the infrastructure to immediately integrate BEV technology into their operations.

In some cases, it could take anywhere from 20 to 30 years to do so, and that's too long a wait for the workers who are impacted by exposure to diesel particulate.

She's hopeful the ministry's recommendations will also require the use of existing technology, such as filters that can be attached to diesel trucks, which can greatly reduce the amount of particulate emitted.

"Minister McNaughton is working in conjunction with the USW Local 6500 to achieve changes, and I'm hoping that he's gutsy enough to keep going, because I do think it takes guts,” Martell said.

“The mining industry's pretty powerful, and everyone needs to work together, because at the end of the day, these workers’ lives are more important than whatever cost it takes to make the mines safer for them.”

The ministry said the first of the regulatory amendments would come into effect on July 1, 2023, while others would be in force on Sept. 1 in an effort to give employers time to comply.