The garbage fire at WM Hillsboro Landfill and the 25-acre brush fire it spawned on Saturday, Aug. 8, were both contained by that evening, with no homes damaged and one firefighter treated for minor overexertion at the scene, according to Tualatin Valley Fire & Rescue.

The cause of the landfill fire remains under investigation.

Multiple callers reported a large column of black smoke rising from the facility at 3205 S.E. Minter Bridge Road around 4:20 p.m. Saturday. Arriving crews found burning trash and tires spanning just over one acre inside the landfill. Flying embers carried south into a dry, 40-acre field of cut grass at 4205 S.W. Minter Bridge Road, igniting a fast-moving brush fire.

Gusty winds drove the grass fire through the field, throwing embers ahead of the flames and sparking additional spot fires. TVF&R described conditions as difficult in its Aug. 8 statement. The brush fire ultimately burned about 25 acres before crews stopped its forward progress Saturday evening and shifted to mop-up operations.

No homes were damaged.

As the flames advanced toward nearby residences, firefighters evacuated two homes as a precaution. Crews positioned around the properties kept fire from reaching either one.

Back at the landfill, two bulldozers cut containment lines around the garbage fire by approximately 7:30 p.m. Firefighters used brush rigs, engines and water tenders to attack the brush fire from multiple directions, a strategy TVF&R said was necessary given the rural terrain.

One Hillsboro Fire & Rescue firefighter working at the landfill suffered minor injuries from overexertion in the heat and was evaluated and treated at the scene. No hospitalization was reported.

Four fire agencies responded: TVF&R as lead agency, Hillsboro Fire & Rescue, Cornelius Fire Department and Forest Grove Fire & Rescue. The Washington County Sheriff's Office handled traffic control on S.W. Minter Bridge Road, which was temporarily closed during the response. Beaverton police deployed a drone to give crews an aerial view of the fire.

As we reported Aug. 9, the fire drew a large multi-agency response to the rural area south of Hillsboro. No formal cause determination has been released, and TVF&R has not announced a timeline for completing its investigation.

Residents with information about the fire can contact Tualatin Valley Fire & Rescue's fire investigation unit.