PA well explosion shoots gas, drilling fluid 75 ft into the air. DEP not notified until hours later, FAA restricts flights within 3 miles of site.

The authors mention that blowout preventers (like the one that failed in Louisiana)  are typically used in situations like this so that workers can control the pressure inside.  After reading this article, I'm still not clear on whether or not a blowout preventer was used.  So did the contractors forget to install one or if they did...did it, too, fail?  

Marcellus gas well blows out in Pennsylvania; gas, drilling fluid shoot 75 feet into air*
By Marc Levy and Jennifer C. Yates, AP

PENFIELD, Pa. -- An out-of-control natural gas well in a remote area of Pennsylvania shot explosive gas and polluted water as high as 75 feet into the air Friday before crews were able to tame it about 16 hours later.

The gas never caught fire and no injuries were reported, but state officials worried about an explosion before the well could be controlled. The well was brought under control just after noon after it started spewing gas and brine, said Elizabeth Ivers, a spokeswoman for driller EOG Resources Inc.

Houston-based EOG, formerly part of Enron Corp., was drilling into the Marcellus Shale reserve, a hotly pursued gas formation primarily under Pennsylvania, New York, West Virginia and Ohio that some geologists believe could become the nation's most productive natural gas field.

There are more than 1,000 Marcellus Shale wells in Pennsylvania alone, some of them within view of homes, farmhouses and public roads.

There were no homes within a mile of the well that blew out.

The accident happened just after the crew finished a process called hydraulic fracturing -- in which millions of gallons of water, sand and chemicals are blasted underground to shatter tightly compacted shale and release trapped natural gas. They were clearing out debris from the well when gas shot out of it, said Dan Spadoni, a spokesman for the Department of Environmental Protection.

Workers evacuated the site and contacted county authorities, said John Sobel, a Clearfield County commissioner. The DEP said it wasn't notified until 1:30 a.m. -- more than five hours after the blowout.

The polluted water flowing out of the well and into the woods was stopped by a trench and a pump installed by a contractor, Spadoni said. Companies that specialize in securing out-of-control wells were called in, he said.

The blowout could test the ability of state regulators, who promised an aggressive investigation into the accident.

"The event at the well site could have been a catastrophic incident that endangered life and property," Department of Environmental Protection Secretary John Hanger said in a statement. "This was not a minor accident, but a serious incident that will be fully investigated by this agency with the appropriate and necessary actions taken quickly."

If the agency finds that mistakes were made, it will take steps to prevent similar errors from repeating, he said. He said it was too early to tell the extent of any environmental damage.

Details about the accident were still sketchy, but the agency was told that unexpectedly high gas pressure in the new well prevented the crew from containing it, Spadoni said.

Ivers said she could not immediately respond to questions about how the accident happened. Public safety and protection of the environment are of the utmost importance, the company said in a statement.

David Rensink, the incoming president of the American Association of Petroleum Geologists, said gas well blowouts are very rare and can be very dangerous to control, since a spark can set off an explosion.

Typically, a blowout preventer -- a series of valves that sit atop a well -- allows workers to control the pressure inside, he said.

Just such a device figured into the massive oil spill off the coast of Louisiana. The oil rig's blowout preventer was supposed to shut off the flow of oil in the event of a catastrophic failure, but it didn't work.

The Pennsylvania well is on the grounds of a hunting club in a heavily forested section of Clearfield County, near Interstate 80 -- about 90 miles northeast of Pittsburgh.

On Friday afternoon, a worker blocked a dirt road to the site, while trucks hauling water tanks streamed past him. He said he was not allowed to talk about what had happened.

As a precaution, the Federal Aviation Administration issued a flight restriction Friday morning, saying no planes below 1,000 feet should go within three miles of the site. The restriction was lifted it shortly after the well was capped.

*This article appeared in Pressconnect.com of Greater Binghamton on 6.4.2010