CLEARFIELD, Pa. - A Texas petroleum engineer arrived here Thursday to investigate last week's natural gas well blowout for Pennsylvania's environmental agency, which now says contamination from the incident may have migrated into a stream.
The Department of Environmental Protection hired John G. Vittitow of Fort Worth to conduct a third-party examination of the accident, the first time an exploration company has lost control of a well since interest in the Marcellus Shale took off.
"We wanted additional expertise," said Neil Weaver, DEP's spokesman.
Vittitow, an expert on well completions, is expected to examine the equipment and records and review the practices employed by the well's operator, EOG Resources Inc., of Houston, and the contractor that was preparing the well to begin production when the blowout occurred June 3.
Nobody was injured in the accident on the well, located at a rural hunting club, and no fire occurred. But DEP Secretary John Hanger has sounded alarms over the operator's performance and cited it as a reason Pennsylvania needs to tax Marcellus Shale gas production.
DEP has suspended the drilling operations of EOG Resources, as well as the operations of C.C. Forbes Co. L.P., the oil-field-services firm whose rig was working on the site. The blowout spewed natural gas and toxic fluids for 16 hours before it was brought under control.
Forbes Energy Services Ltd., of Alice, Texas, said Thursday that it had "voluntarily and proactively" idled the two Marcellus Shale rigs operated by its subsidiary and is cooperating with the investigation.
"Idling of the two rigs will have no material impact on our future results of operations," John Crisp, Forbes Energy's chief executive officer, said in a statement.
DEP's Hanger said Forbes had not been cooperating "to our satisfaction."
In an interview on Pennsylvania Cable Network on Wednesday night, Hanger said that investigators had tried to question Forbes workers, but that the company "had directed its employees not to talk to us without representatives present."
DEP has characterized the environmental damage from the incident as "modest," but Hanger indicated Wednesday that some fluid might have escaped into a nearby stream.
The agency said 35,000 gallons of fluids were collected after the blowout. Most were contained on the gravel site where the well is located. DEP initially said a spring nearby showed a spike in "conductivity," indicating it had been contaminated with saltwater associated with gas-well production fluids.
But late Wednesday, agency spokesman Weaver said a water sample taken Monday in an unnamed tributary of Little Laurel Run 2,000 feet from the spring "displays elevated conductivity and other parameters often associated with flow-back water from drilling activities."
"This indicates that some fluid was not effectively captured or there may be an additional pollution source," Weaver said. "EOG's environmental staff and their environmental consultants will continue to sample in this area."
EOG is developing dozens of wells in the area in partnership with Seneca Resources Corp., which owns the leases. Some are in Moshannon State Forest, which abuts Punxsutawney Hunting Club, where the accident occurred.
DEP has not yet released detailed tests of the spill or the well's wastewater that would indicate whether the fluid contained any heavy metals or toxic elements that reside in deep geologic formations, such as barium, radium, arsenic, or strontium. The tests might also indicate whether any of the three chemicals EOG reported it used during the hydraulic fracturing at the site in May had escaped from the well.
In "fracking," high-pressure water, sand, and chemicals are injected into a well to shatter the shale to release trapped natural gas. Sand particles remain in the hairline fractures to allow pathways for the gas to escape. Much of the wastewater is recovered and recycled or treated and disposed of.
EOG said the three chemicals it used in its frack fluid amounted to 0.135 percent of the total volume injected into the well. The additives reduce the fluid's friction and inhibit formation of scale or bacterial slime that clogs fractures and reduces gas flow.
Frack fluids or exotic toxic elements found in the rock are of less concern to environmental officials than the potential damage from chlorides - salt - that can pollute drinking water and harm aquatic life.
In his TV appearance, Hanger assured viewers that the state had not yet experienced an instance where frack fluids had contaminated supplies of underground drinking water. Afterward, Hanger said it was too early to tell whether the Clearfield blowout would affect groundwater.
Elizabeth M. Ivers, an EOG spokeswoman, said the well itself appeared to be undamaged. If it were ruined, it would represent a significant loss; such wells typically cost about $4 million to develop.