One haul-truck rolled over and a maintenance truck caught fire on the ice road to the N.W.T. diamond mines in the last two weeks, CBC News has learned.
That's on top of the five truck incidents — including three cabs catching fire — in Yellowknife or on the highways leading to the ice road during roughly the same period.
The maintenance truck fire happened at the Lac De Gras camp, located about 350 kilometres down the 600-kilometre ice road.
There were no injuries in either incident.
The number of incidents, now totaling seven, is spurring an investigation by the joint committee of diamond mine owners that manages the ice road.
"As a result of the fires that have taken place this year, we're reviewing all of our procedures not only for winter-road-related trucks on public highways, but also on the winter road itself," says Ron Near, the director of the Tibbitt to Contwoyto Winter Road Joint Venture between Dominion Diamond Corporation, Rio Tinto and DeBeers.
Common causes to be probed
Fires anywhere along the route "are very, very rare," added Near.
"I think in the last five and a half years that I've been on the project, I think I recall one minor fire at Lockhart Lake camp.
"So it's something that hasn't happened to the extent that it's happened this year."
"The number of fires in particular is very unusual," echoed Wally Schumann, the minister of Transportation in the legislative assembly Monday afternoon.
"I believe the joint venture is going to have ongoing meetings with contractors and try to get to a conclusion on what's causing these issues. They're... seeing if there's something that needs to be changed or put in place to mitigate these [incidents]."
The official website for the ice road — which does not appear to have updated its security statistics since 2011 — does not list the number of rollouts or fires on the road.
The investigation will look for common causes among the incidents, confirmed Near.
It will also look at options for fighting truck fires that happen on parts of the ice road far from one of the three camps where there is fire extinguishing equipment.
"You're limited because you don't have a fire department present," said Near.
He couldn't say when the report coming out of the investigation will be finished.
Damaged hose likely caused 1 fire
The causes of most of the seven recent incidents are not yet known.
But the City of Yellowknife's fire division has cited a likely cause for why the cab of a Ventures West truck caught fire on the Ingraham Trail on Feb. 22.
"The driver heard a noise from the engine compartment and lost oil pressure, plus there was oil on the highway, so a blown/damaged hose was likely the cause," said Dennis Marchiori, the city's director of public safety.
Jasper Lamouelle, the president of the Tlicho Investment Corporation — which owns Ventures West — says given the number of trucks and the volume of materials travelling to the mines, accidents are bound to happen.
"We've had two rollovers so far and one burnout," he said. "We do about 80 per cent of the loads. There's 9,000 loads. We're doing 7,000 of them.
"We take great pride in, two decades ago, having nothing to having something today, where we're managing 80 per cent of the total loads to the diamond mine resupply.
"Out of the total loads we've had, these are expected."
'Cause is unknown'
Another truck cab caught fire in the RTL Robinson truck yard on Yellowknife's Old Airport Road last week.
"The truck in the RTL/Westcan yard was idling and after we extinguished the flames, there was not enough to make a determination as to cause, therefore, the cause is unknown," said Marchiori.
The most recent incident near Yellowknife involved a truck whose cab caught fire near the Yellowknife River bridge on Saturday.
That truck is owned by an independent contractor hired by Grimshaw to deliver supplies to all three diamond mines.