Two contract workers were hurt, one critically, on Wednesday in far western Colorado’s Mesa County while working on a valve at an Encana Corp. gas well that ruptured, a Denver-based company spokesperson told NGI Thursday.

“There was a small spill of produced water, which was contained, and we’re in the process of investigating the incident,” the spokesperson said. “Our primary concern is the health of these two men.”

News media reported that one man was airlifted to a local hospital in critical condition, and the second man sustained less severe injuries and was taken by ambulance to receive medical care. The second worker was later released from the hospital, according to Encana.

“Early [Wednesday] afternoon, two contractors working on an Encana well site near De Beque, CO, were injured while working on a valve,” the spokesperson said. “Both were taken from the scene for treatment.”

The wellsite involved is located in part of the Piceance Basin near Grand Junction, CO.