A controlled fire is burning two miles southwest of Mackay.
According to a news release from the U.S. Forest Service on Tuesday, the fire began May 29 and is burning about 1,800 acres.
The purpose of the White Knob Hazardous Fuels Reduction Project is to reducing the chance of severe, wildfire in the area that would threaten Mackay's municipal water supply, as well as the historic mining structures in the area.
The project began in 2011. Prescribed burning was planned in nine units, or 4,700 acres, of which about 3,000 acres have burned.
The Forest Service said smoke will continue to be present in the Cliff Creek drainage as well as Horseshoe Canyon until significant rainfall occurs or available fuels are consumed.
The area is being monitored by crews from the Salmon-Challis National Forest.
The Lost River Ranger District has closed FR 532 from the bottom of Cliff Creek to Ausich Cabin to protect the public and fire personnel.