The fire began Monday night at a Salt Lake City green waste area. This areas holds chopped up trees and green waste used to make mulch.
Investigators did not know the cause of the fire. The fire was contained to a waste pit about 200 by 300 feet Monday night.
Fire crews are working to put out a fire in the same area Tuesday evening.
Witnesses reported seeing flames shooting up into the air. The wind blew smoke into neighboring areas.