The Sublette County Sheriff's Department said one worker was in critical condition, two were in serious condition, one was stable and a fifth was treated and released from a Pinedale clinic.
Doug Hock, a company spokesman, said the explosion occurred near a battery of six condensate tanks. Two of the injured workers were contract welders and the other three were employed by ASAP Construction, the Casper (Wyo.) Star-Tribune reported.
“This appears to be related to the welding they were doing,” Hock said. “That was the ignition source.”
The sheriff's department said the explosion took place at 10:15 a.m. MST and the fire was put out by 1 p.m. MST.
The cause of the accident will be investigated by the Occupational Safety and Health Administration, the Star-Tribune said.
“This has been a difficult and sad day, and our friends and co-workers that were hurt are in our thoughts and prayers,” Encana spokeswoman Bridget Ford said.
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