WRIGHT - The condition of Wright resident Marsha Iriberry, 23, was improved from fair to good Wednesday as she continue to recover in the intensive care unit at Campbell County Memorial Hospital. She suffered severe injuries in a Sunday afternoon pipeline explosion that killed a fellow co-worker.

Debra Lee Zeleny, 41, of Gillette, died at the scene of the accident in northern Converse County, according to Converse County Sheriff officials. A former waitress and grocery checker, she went to work as a pumper for Merit, a job she enjoyed because it allowed her to be outdoors, according to her family.

Both women were working for Merit Energy Co. at the time of the accident. According to reports, the two may have been attempting to depressurize a natural gas pipeline when it ruptured and exploded sometime around noon Sunday.

"There was no fire involved at all. It appeared to be a pressure explosion of the pipeline," said Sgt. Steve Nunez of the Converse County Sheriffs Office.

Johnnie Hall, Wyoming Worker Safety compliance supervisor, said his agency has completed a field investigation of the accident and is waiting to interview Iriberry, the only living witness to the accident scene.

So far, no citations have been issued. Hall said his agency cannot release all details of the accident until the investigation is complete. If any Occupational Safety and Health Administration (OSHA) rules are found to have been violated, citations will be issued at that time, he said.

Merit Energy declined to comment on the accident.

Hall said the women were with a crew attempting to clean out the pipeline with a "pig" - a sphere-shaped device sent down pipelines to clean out unwanted material.

Nunez indicated his report concurs, and said a second pig was sent down the pipeline in an attempt to free up the first pig. The pipeline crew was working from two different pressure stations and reportedly sent the two women to open a valve somewhere between, Nunez said.

"They don't know if (the two women) got the valve open," Nunez said. "They did not answer their radio when the guys were calling them to see if they were OK so they sent someone out to look for them." Workers who first came to the accident scene discovered the valving had been blown out of the ground, Nunez said.

Sheriff, ambulance and fire responders from Glenrock, Gillette and Wright were dispatched to the remote location about midway between Wright and Glenrock. Nunez said responders requested Life Flight air ambulances from Casper and Rapid City, but snowy weather prevented a dispatch from either site.

A ground ambulance from Wright was the first on the scene.