BIG TIMBER A wildfire south of here nearly doubled in size Wednesday, prompting officials to urge hundreds of residents in Stillwater and Sweet Grass to evacuate.
The Derby Mountain fire was estimated at 80,000 acres, or about 125 square miles.
There were reports Wednesday evening that two homes and several outbuildings in Sweet Grass County had burned, said fire information officer Pat Cross. He had no further details, and personnel in the Sweet Grass County Disaster Emergency Services were not immediately available for comment.
The Stillwater Mine called off its night shift because of smoke from the fire, and Interstate 90 was temporarily shut down between Livingston and Columbus.
The fire camp used as a base of operations was evacuated at 4 p.m. because of encroaching flames, Cross said. About 30 firefighters stayed behind to protect a handful of nearby homes, he said.
Kerry O’Connell, Disaster and Emergency Services coordinator Sweet Grass County, said her office was calling everyone who had not already left the evacuated areas to let them know the situation was deteriorating.
“This fire is really starting to rock and roll,” she said.
As of 6:30 p.m., the areas under evacuation in Stillwater County were Meyers Creek Road, Curry Flat Lane, Limestone Road, Cow Face Road, Stockade Road, Spring Creek Road, Stillwater River Road to Johnson Bridge on the east, and the town of Nye.
Areas under evacuation in Sweet Grass County were Hump Creek Road, Mysse Road, Bridger Creek Frontage Road, Stockade Road, Main Bridger Creek Road to I-90 from the intersection with West Bridger Creek, Work Creek, Lower Deer Creek and West Bridger Creek.
Stillwater County Public Information Officer Karen Tyra said the county had also initiated pre-evacuation alerts for areas west of Columbus up to I-90.
The Stillwater Mining Co. canceled its Wednesday night shift at the Stillwater Mine near Nye because of concerns about travel conditions, company spokesman John Beaudry said.
About 200 employees were affected. Beaudry said supervisors would decide by 3:30 a.m. whether to cancel Thursday’s day shift. A phone number 406-322-8777 was set up for the mine’s 1,000 employees to receive updates.
The fire was moving away from the mine and did not appear to be posing an immediate threat.
“The real concern is smoke on the roads and people getting hurt,” said Greg Wing, the company’s chief financial officer.
Incident Commander Glen McNitt told a group of about 100 people at a public meeting in Big Timber Wednesday morning that the fire exhibited extreme behavior Tuesday evening.
Winds were erratic, pushing the fire in unexpected directions, he said. Embers blew across defensive lines and spotted in heavy timber.
“It became a plume fire that makes its own weather,” McNitt said. “It created its own winds. It even created its own lightning. There was lightning in the plume last night.”
Firefighters are facing the lowest fuel-moisture levels on record, McNitt added.
“Kiln-dried lumber has a 15 to 16 percent fuel moisture. Fuels here are down to 8 percent,” he said. “They are twice as dry as what you get from a lumber yard.”
Some residents in the evacuation or pre-evacuation are stayed put Tuesday and were hoping to hold out through Wednesday.
“We’re not going to take you out in handcuffs,” Sweet Grass County Undersheriff Jerry Mahlum told those gathered at the meeting. “We are going to ask you to sign a waiver that you’ve been warned and to let us know the next-of-kin you want notified.”
The Red Cross set up a shelter in the Big Timber Civic Center on Tuesday night, but no one stayed overnight.