Worland firefighters spent Friday night trying to extinguish a sulfur mound that had caught fire.

Crews had to wear full protective gear and self-contained breathing apparatuses due to the presence of sulfur dioxide, a hazardous gas emitted by the eery flames.

It was a dangerous situation that required careful management on the part of first responders. Only a small amount of water was used to cool the surface of the burning sulfur below the molten stage, as adding water to sulfur dioxide gas creates sulfurous acid, which can be related to "acid rain."

The fire was burning in a bowl-shaped area, so all "runoff" collected in the area of the blaze. Fire managers had to use caution in placing personnel, in addition to diligently monitoring the weather conditions and their effect on the smoke and chemical plume.

According to Worland Fire Protection District No. 1 and the Worland Volunteer Fire Department, the sulfur deposits in Washakie County are leftover from the Texas Gulf Sulfur Plant that operated north of Worland during the 1950s. Much of the sulfur is mixed heavily with soil and is not 100 percent sulfur concentrate.

"This is a type of fire that is not common but needs to be addressed and dealt with safely and quickly," the District wrote on its Facebook page. "Fortunately the WFD has hazmat technicians and we have an understanding of this as we deal with H2S and SO2 on a somewhat regular basis."