A massive fire at the county landfill on Sunday probably was started by heavy equipment work, according to a fire official.

Assistant Fire Chief Russ Sappington with West Valley Fire and Rescue said firefighters  spoke with the operator of a front-end loader that had been moving items in the large pile of appliances at the landfill.

“He just seems to think that he hit something that started a spark,” Sappington said.

That spark may have hit something flammable in the 900-ton mound of lawnmowers, washing machines, microwaves and other appliances.

Sappington said that the loader operator tried to scoop the initial fire out of the pile but the wind fanned the flames.

Jim Chilton, landfill operations manager for Flathead County Solid Waste, said that landfill workers deployed a water tanker that was on site, but it was of little help.

The result was an intense fire that burned for nearly six hours. Seven fire departments battled the roaring flames and roiling black smoke — a spectacle that attracted hundreds of spectators.

The fire has been deemed an accident, Sappington said. By 8:45 p.m. Sunday, it was nearly put out.

Sappington praised the mutual aid response from fire departments around the Flathead Valley for what proved to be one of the larger fires in his experience.

“This is a new one for me,” he said. “I’ve been on 16 years, and this was a pretty good one.”

Reporter Matt Hudson may be reached at 758-4459 or by email at mhudson@dailyinterlake.com.