Fire officials say the blaze that was first reported on Bureau of Land Management property Tuesday was about 30 percent contained Wednesday morning, and no structures or people are threatened.
A helicopter flight Wednesday afternoon aimed at surveying the blaze from above found it only covered roughly 250 acres, half of the original estimate.
Two firefighters suffered from heat exhaustion on Tuesday and were treated. More than 100 firefighters are on the ground, and helicopters are also working at the scene.
Officials tell The Salt Lake Tribune they believe the fire was sparked by someone burning debris.
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