A 50-foot-high flare is expected to continue burning for three or four more days at a Marcellus shale gas well in West Virginia's northern panhandle where an explosion injured seven workers Monday.
Drillers hit a pocket of methane in an inactive deep mine, triggering the morning blast.
Kristi Gittins, a spokeswoman for Chief Oil & Gas LLC, owner of the well, said Tuesday that well-fire specialists with Wild Well Control, a Texas firm, have already started removing the melted drilling rig damaged in the explosion in a rural area outside Moundsville, 55 miles south of Pittsburgh.
She said the company plans to cap the flare, which continues to be fed by methane from the inactive Alexander Mine owned by Consol Energy, by the end of the week.
"It's a low-pressure flare that's under control. We don't anticipate any well bore damage. We'll want to look and find out what happened," said Ms. Gittins. "We do anticipate we will continue drilling at the site but there's no schedule for that at this time."
All seven workers on the rig, two employed by subcontractor BJ Tubular Services of Houston and five from Union Drilling, headquartered in Fort Worth, Texas, suffered burns and were taken to the West Penn Burn Center in Pittsburgh. Five have been released. Two remain hospitalized, but their injuries are not considered life threatening.
The well they were working on was one of hundreds that have been drilled into the Marcellus shale formation, which underlies three-fourths of Pennsylvania and parts of West Virginia, New York, Ohio and Maryland, and contains an estimated 363 trillion cubic feet of natural gas. But getting the gas out of the shale requires drilling companies to pump millions of gallons of water, sand and chemicals into the shale under tremendous pressure to fracture or "frack" the sedimentary rock formation.
Kathy Cosco, a spokeswoman for the West Virginia Department of Environmental Protection, said Tuesday afternoon that the department had started an investigation of the accident and is considering a number of response options, including ordering a halt to all drilling and fracking by the companies involved.
"At this time, the inspectors do not want to speculate on what might have ignited the flame until we are further into the investigation and have had a chance to talk to the companies involved," Ms. Cosco said.
Chief owns 15 Marcellus shale wells in West Virginia and 60 in Pennsylvania.
One well into the 8,000-foot-deep Marcellus shale formation had already been completed on the pad outside Moundsville. Drilling for a second well on the pad had been going on for two days and reached 1,000 feet deep when the explosion occurred.
Prentice Cline, assistant area director for the Occupational Safety and Health Administration in Charleston, said the agency has two inspectors on site and is pursuing interviews with all of the workers on the rig. The agency does not discuss findings of ongoing investigations, he said.
Union Drilling has had more than two dozen violations of OSHA workplace safety rules and been fined a total of $226,000 in the past five years at drilling sites in five states.
Ms. Gittins said Chief Oil & Gas was not aware of Union Drilling's OSHA violations. She said Chief has subcontracted drilling operations to Union for at least 10 years and Union drilled the first well on the pad where the explosion occurred without incident.
"We are using them at another location in Pennsylvania now," she said, "and have no plans to change that."
Don Hopey: email@example.com or 412-263-1983.