The West Fork Fire northwest of Libby is causing concern among Lincoln County officials as the fire draws closer to the defunct W.R. Grace & Co. vermiculite mine.

The big question is how much asbestos potentially could be carried by the smoke, Flathead County Sheriff Chuck Curry told the county commissioners during a fire briefing Tuesday morning.

“The fire is moving that direction,” Curry said. “They threw a lot of resources at it. They were hauling loads of logs out not even limbed. They were cutting fire lines like crazy. I know they’re very concerned about it because they are in the fall zone.

“We’ve had discussions with Lincoln County officials and they’re very worried about that,” Curry said. “Over the years we’ve had discussions with the Forest Service about how much of the asbestos from that site would be carried by the smoke.”

Curry said he contacted Flathead City-County Health Department Public Health Officer Hillary Hanson, who “put some people on it” and contacted the state Department of Environmental Quality and U.S. Environmental Protection Agency about the potential for asbestos-saturated smoke.

“She was assured by the EPA experts their studies have shown that should the fire burn over that heavily asbestos-laden forest, 95 percent of the asbestos would be contained in the ash,” Curry told the commissioners.

The remaining 5 percent would be carried by the smoke — and prevailing winds often blow smoke from the west toward Flathead County — but studies show the asbestos-contaminated smoke “would precipitate out fairly rapidly,” he said.

While firefighters on the West Fork Fire would have to deal with the toxic ash, the asbestos shouldn’t be a problem for Flathead County, Curry said.

Asbestos exposure linked to the mine has killed hundreds and sickened thousands in the Libby area.

The lightning-caused West Fork Fire was detected Aug. 30 about 7 miles northwest of Libby in the Quartz Creek/Bobtail Ridge area. It quickly escaped containment efforts due to extremely dry fuel and critical fire weather patterns.

On Sept. 4 the Rocky Mountain Incident Management Blue Team assumed command of the fire. The Blue Team is working closely with the Lincoln County Emergency Operations Center and the Lincoln County sheriff.

As of Tuesday afternoon the fire had burned 13,372 acres. Officials estimate containment by Oct. 7.

Evacuation orders are in effect for the 17 Mile Community of Pipe Creek Road; Upper Bobtail Road; north of and including Hutton Drive, along with Milton Drive, Bobtail Lane, Verna Court; and Quartz Mountain Road.