A new "Helowell" has been put into operation at the 420-acre Sawtooth forest fire southwest of Hamilton.

The bladder holds retardant that is mixed at the site, and the helicopter an then dip out of the tank and drop it in areas that are otherwise inaccessible. About 7,800 gallons were used Thursday at the fire, which is in the Sawtooth Canyon, north of Sawtooth Creek and south of Canyon Creek.

An information booth is open in the afternoons at US 93 and Roaring Lion Road, south of Hamilton. Sawtooth Creek Trail #123 is closed while the fire is active.

On the north end of Selway-Bitterroot Wilderness, the Powell SBW Fire Complex has reached US 12, causing more smoke to cause more caution from travelers. The road remains open, though there is more fire-related traffic. The Powell complex grew about 1,800 acres Thursday.

At the south end of the Bitterroot National Forest, the Mustang Complex is now listed at 252,000 acres and has not yet reached US 93, though there are 35-mile per hour speed limits on portions of the roadway, which remains open. The Salmon River Road is also open, according to Salmon-Challis National Forest officials.

The Mustang Fire has crept into the Bitterroot National Forest. Crews are building a line between last year's Saddle Fire and this year's Chrandal Fire, ahead of the Mustang Fire. Evacuation notices and structure protection have been completed in the Hughes Creek area. The fire is also a threat to Lost Trail Powder Mountain.

Air quality has been "good" all morning in the Hamilton area, but officials say the smoke will return this weekend.