SPRINGVILLE TWP. - An explosion at a natural gas compressor station in Susquehanna County on Thursday morning blew a hole in the roof of the complex holding the engines, shaking homes as far as a half-mile away and drawing emergency responders from nearby counties.

The 11 a.m. blast at the Lathrop compressor station off Route 29 sent black and gray clouds billowing from the building for several hours, but the damage was contained to the site and no one was injured, said a spokeswoman for Williams Partners LP, which owns the Lathrop station.

Automated emergency shutdown procedures stopped gas from entering or leaving the compressors, and Williams will do a full investigation of the cause and damage as soon as it is safe to go back into the building, Williams spokeswoman Helen Humphreys said.

"The emergency shutdown equipment did work properly to isolate and minimize the incident," she said. "Emergency procedures were immediately activated. That included notifying local authorities and first responders, and evacuating all personnel."

The Lathrop station pressurizes and dehydrates natural gas from Marcellus Shale wells in the county for transport through interstate pipelines, including the Tennessee and Transco, which bring the gas to market. The station was sold to Williams by Cabot Oil and Gas Corp. as part of a deal announced in 2010 that also included a second compressor station and 75 miles of the natural gas drilling company's gathering pipelines.

Cabot spokesman George Stark said the company was working at its well sites Thursday to make sure they were not sending gas to the Lathrop station. He was unable to provide an estimate of how many wells were influenced by the interruption.

"We're working on rerouting the gas to other, operating compressor stations," he said. "We've got multiple ways we flow our gas."

In a press release Thursday, Cabot referred to the incident as a "flash fire, which extinguished itself immediately" and said it was moving approximately 365 million cubic feet of gas per day through the station before it was shut down.

"The investigation has just begun as to equipment damage, if any, the length of disruption or potential impact," Cabot CEO Dan O. Dinges said in the statement.

Colleen Connolly, a spokeswoman for the Department of Environmental Protection, said regulators were alerted to the explosion at around 11:30 a.m., and inspectors spent the afternoon monitoring air quality around the site after gas escaped from the station.

"The natural gas release valve was quickly shut off," she said. "So far, the levels are coming back acceptable, and there is no danger to the public."

The DEP has permitted seven compressor engines for the site, although it was unclear Thursday how many were running at the time of the fire.

"We're going to begin a full-scale investigation into how this happened," she said, "what was going on up there and the situation with the permits - how many compressors were operating up there and how many they were allowed to operate."

Annette Allen was ready to evacuate with her cats late Thursday morning after she heard the boom.

Sitting in her home on Route 3004, Ms. Allen said she listened intently to the scanner as emergency officials spoke about using foam to put out a fire at the compressor station on state Route 29.

"I had my cat cages set, ready to go if they did evacuate us," she said. "It was a big explosion, a big whooshing sound."

She said she now worries that a larger explosion will destroy her home and others.

Peter Patel, owner of Checkered Express in the center of the town on state Route 29 at Route 3004, recalls seeing many firefighters and other officials passing by his store to the site.

"We saw everybody run and we knew something big happened," he said, adding it was the biggest event he has experienced in the last six years as the owner of the convenience store and gas station.

Springville Volunteer Fire Company First Assistant Chief Jason Rinker said more than seven fire companies responded.

"It was hectic," Assistant Chief Rinker said.

After the explosion, he said Williams officials shut down lines to the compressor station.

"We let the gas burn off itself," Assistant Chief Rinker said. "Once things calmed down, we extinguished the fire that was there."

He described the fire as smoldering and said the response to this incident was similar to how a fire company would respond to a propane tank explosion and fire.

"It was business as usual," he said.

Hilda Loch, who lives on Route 29 down the street from the site, did not think she was in danger, but she said the boom did catch her attention.

"I didn't think I was in too much danger down here," she said. "I thought it was thunder."

Mrs. Loch, who was speaking on the phone with a friend when the explosion happened, realized it was too loud to be thunder, however.

She and her friend ended their discussion on the phone.

Burton Miller, who lives about half a mile across a field from the compressor station, heard a "big bang" that shook his house.

"Nothing fell off the shelves," he said, "but it did shake everything pretty good."

He did not immediately connect the sound to the compressor, he said, so it wasn't until he got a phone call 30 minutes later about the incident that he first glanced at the station.

"I looked out the window and I saw the building all blown apart up there and smoke," he said. "A lot of the roof and metal siding is all gone."

Paul Karpich, who lives about a quarter mile from the compressor station, said he heard a "boom" but it was not remarkable.

"I hear a lot of noises from over there," he said.

He walked over the hill separating his home from the station to see part of the roof missing on the enclosure, a 12,000-square-foot building, he said.

An official with the Susquehanna County Emergency Management Agency said all questions about the incident were being directed to Williams. Wyoming and Lackawanna county fire companies were called to provide backup Thursday morning, including the Chinchilla Hose Company in South Abington Twp., which was asked to provided the foam material to help contain the gas and fire.

Vera Scroggins, a critic of natural gas development, said she followed fire trucks to the compressor station Thursday morning and could see "a black, dark gray smoke" coming from the middle of the complex, but no visible flames.

Fire crews were ringing the property and using a bucket to raise firefighters to get a better view of the structure enclosing the compressors, she said. All fire crews had left the scene by about 5 p.m.

Williams recently completed a 34-mile high-pressure pipeline from the Lathrop station to the interstate Transco pipeline in Dallas Twp., Luzerne County.

The connection and metering station is about half a mile from the Dallas district schools.

Dallas Twp. supervisor Liz Martin expressed concern Thursday morning that the explosion would send a surge of gas toward the metering station, but Ms. Humphreys from Williams said that was not possible.

"It's hitting so close to home it's not even funny," Ms. Martin said. "I'm still shaking inside because it could easily have been here."

JOSH MROZINSKI and ELIZABETH SKRAPITS, staff writers, contributed to this report.

Contact the writers: llegere@timesshamrock.com, jmrozinski@timesshamrock.com,eskrapits@citizensvoice.com

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