Company says blaze was contained by on-site rescue team
Workers at a northern Manitoba nickel mine sheltered in designated safety locations Thursday after a fire involving a piece of equipment broke out underground — the latest incident at a site that changed hands just weeks ago.
Exiro Metals confirmed in a Friday statement that the fire occurred at its T3 mine in Thompson, Man. Workers followed “established safety procedures” and relocated to safety locations while the mine rescue team extinguished the blaze, according to CBC News. No injuries were reported and Thompson Fire and Emergency Services was not called.
“We appreciate the professionalism of our employees and emergency response personnel in responding to the situation,” Exiro said. The area was confirmed safe before employees returned to work, and the incident is under investigation. Manitoba’s Workplace Safety and Health branch had not issued a statement as of publication. COS has contacted the regulator.
New owner, familiar hazard
Exiro Nickel Company closed its acquisition of Vale Base Metals’ Thompson Operations last month, taking over a nickel complex comprising the T1, T3 and Pipe mines plus a concentrator. A consortium of Exiro Minerals Corp., Orion Resource Partners LP, and Canada Growth Fund Inc. holds an 81.1% stake, with Vale retaining 18.9% and the group committing up to US$200 million.
It is not the first emergency the Thompson operation has seen. The site experienced an underground fire in 2015 that forced workers to shelter overnight in a refuge station, per CBC News. A December 2019 fire in the mill concentrator — confirmed by the Thompson Citizen and Thompson Online — sent two employees for smoke inhalation treatment while T1 and T3 workers were moved to refuge stations.
The pattern extends across northern Manitoba. COS has reported that a 2022 fire at Hudbay Minerals’ Lalor mine near Snow Lake trapped 177 workers for hours; equipment caught fire twice with no injuries — a stark illustration of how quickly an equipment fire becomes a mine-wide emergency.
Fire ranked a top risk in underground mines
These incidents reflect a hazard the industry has formally elevated. In March 2023, Ontario mining subject matter experts met for a Ministry of Labour-facilitated workshop with Workplace Safety North, ranking “major fire underground from mobile equipment” among the top 10 health and safety risks in underground mines. Fire and explosion events accounted for 19% of risk categories — second only to equipment and machinery incidents at 43%.
The growing use of battery electric vehicles underground has sharpened that concern. Safety experts say battery fire risks remain poorly understood as the sector transitions to the technology. Justin Arsenault, fire chief at Agnico Eagle’s Detour Lake Mine northeast of Timmins, Ont., told CBC News that lithium-ion battery fires require large quantities of water to extinguish and can reignite even after appearing doused.
Exiro has not disclosed whether the equipment involved was battery-electric or diesel-powered — a detail investigators will likely scrutinize, given the distinct suppression challenges each fuel type presents in an enclosed underground environment.
Refuge stations: a last line of defence
That workers reached safety without injury reflects the value of well-practised emergency response plans. COS has documented how risk assessment drives effective mine rescue planning in Canada, with clear role assignments and regular drills at its core.
Refuge stations — sealed underground chambers equipped with breathable air, communications, water, and first-aid supplies — are mandated under provincial mining legislation and must be located close to active work areas. Manitoba mine operators are governed by The Workplace Safety and Health Act, C.C.S.M. c. W210, and the province’s Operation of Mines Regulation.
In Canada, mining health and safety is the primary responsibility of provincial and territorial governments, each maintaining its own legislation and Chief Inspector of Mines. The cause of the Thursday fire had not been disclosed as of publication.
