Spontaneous combustion on another warm early-fall day ignited a 400-square-foot-area of a mulch pile at Deschutes County’s Knott Landfill in southeast Bend on Sunday, officials said.

Bend fire units responded around noon to the reported fire at the landfill at 61050 SE 27th Street, said Bend fire Capt. Andy Hood. Two Central Oregon Interagency Dispatch Center units also responded, as the smoke was visible from the Lava Butte fire lookout, Hood said.

They arrived to find the fire burning in a narrow section of the 40-by-100 foot, 4-foot-deep pile of organic recycled yard debris, ground up to the consistency of “hog fuel,” Hood said. The pile was in an isolated area of the landfill, with no threat to other facilities or areas, he added.

Water was applied to cool the blaze until landfill employees arrived. The fire was then turned over to those workers, who used heavy equipment to separate the pile and put it out with the water resources on scene.