Investigators confirmed a lightning strike caused a natural gas leak Wednesday night resulting in a temporary evacuation of nearly 100 residents living near a large gas processing plant in Chartiers Township.
The incident also caused MarkWest to limit operations at the plant on Western Avenue until a full assessment is completed on the emergency, which did not result in any injuries, the company stated in a Thursday news release.
“Additionally, there are no apparent signs or evidence of a fire,” the company stated.
The state Department of Environmental Protection sent an investigator Wednesday night to the plant, which resulted in a report placing the blame for the propane leak on a 6 p.m. lightning strike, said John Poister, DEP spokesman in Pittsburgh.
“This was an act of nature,” Poister said.
He said while the investigation at MarkWest continues, it didn’t appear the company would be cited for violating any environmental regulations over the incident.
The plant went under emergency shutdown following the lightning strike that damaged a pipe to a de-ethanizer chamber, where ethane is removed from the natural gas, Poister said.
The chamber leaked only the propane that remained in the plumbing “for a short duration,” he said.
It was a significant enough leak to require the evacuation of people living within a two-mile radius of the plant.
The DEP was even more concerned that another lightning strike would cause additional damages to the facility, something that didn’t happen during the storm, Poister said.
Washington County Public Safety Director Jeff Yates confirmed Thursday the incident didn’t result in a fire.
He said investigators initially thought the flames from the gas flares were involved with the leak because of the way they lined up with it from a distance.
Two flares at the plant remained in operation throughout the course of the event.
The company said it was working Thursday with its customers and routing some gas to the Majorsville complex in Marshall County, W.Va.
Yates said MarkWest is consulting with a forensics expert to determine the volume of propane that leaked Wednesday.
He said there is an evacuation plan in place for the MarkWest plant, as there are for many facilities across the county. Those plans, he said, identify the roads to take people away from an incident and the locations of shelters. He said the evacuation plan for MarkWest was followed Wednesday.
“Nobody wants to be forced out of their homes,” Yates said.
Some of the residents were directed to a local fire department and then permitted to return to their homes before 10 p.m.