Friction from wedged rock may have caused truck fire at Nunavut mine

A haul truck similar to this one caught fire Monday Dec. 30 at the Meadowbank gold mine, located 70 km north of Baker Lake. (PHOTO COURTESY OF AGNICO EAGLE/FLIKR)

Workers at Agnico-Eagle’s Meadowbank mine witnessed a pre-New Year’s fire display Dec. 30 when an industrial haul truck burned for hours into the night at the gold mine, which is located about 70 km north of Baker Lake.

The $2-million, 150-tonne Caterpillar truck caught fire in the late afternoon. The likely cause was friction created by a rock that became wedged against one of its enormous back tires.

“It was arriving on one of the waste dumps to dump its load and a fire erupted in the rear of the truck,” said Dale Coffin, director of communications at Agnico-Eagle Mines.

“The operator reacted very well and was able to secure the truck and leave it uninjured, and [he] found refuge with a [bull]dozer operator that was operating near by,” Coffin said.

Something must have happened to the truck’s “de-rocker” mechanism in the back tire to start the fire, Coffin suspects.

“We do have a mechanism on every truck on both rear wheels where its sole purpose is to dislodge all rocks that may get wedged in there,” Coffin said.

“For whatever reason it didn’t dislodge the rock and over time the friction built up to a point where there was spontaneous combustion of one of the tires,” he said.

Coffin said each one of the truck’s tires costs $35,000.

“They’re rubber, and these massive tires burnt for some time before they put themselves out,” Coffin said.

The gold mine is fully equipped with a 24-hour, seven-day-a-week firefighting service. But the emergency crews could only watch the truck burn.

“They allowed it to burn. They stood back and allowed it to burn to a point where hours later it mostly extinguished itself,” Coffin said.

Coffin said the investigation into the fire will “identify the cause of it, and if there’s any corrective measures we need to take to ensure it doesn’t happen again, we will do so.”

Coffin also said the fire will not affect production at the mine, because Agnico-Eagle has 11 similar trucks at Meadowbank.

Scrap steel from the burned truck will be cut up and shipped south at a later date Coffin said.

“We’re very grateful nobody was injured. And we’re looking forward to a safe and productive 2014,” Coffin said.