Cause of Plum house explosion could take months or years to find, authorities say

Five people, four adults and one child, died in a massive house explosion in Plum on Saturday, borough police Chief Lanny Conley said at a news conference Sunday.

None of the victims from the incident that destroyed three houses and damaged scores of others on Rustic Ridge Drive have yet been officially identified but family members confirmed for the Tribune-Review that two of the victims are Casey Clontz, 38, and his son, Keegan, 12.

Official identification is expected to take some time as it will involve use of dental records and, potentially, DNA for formal identification, authorities said.

Three people were rescued. Of those, two have been treated and released from hospitals while one was last known to be in critical condition, said Steve Imbarlina, deputy director of fire and emergency medical services for Allegheny County.

No further updates on that person’s condition are expected because of privacy laws, he said.

As of Sunday afternoon, everyone was believed to have been accounted for, Allegheny County spokeswoman Amie Downs said.

The cause remains under investigation and may not be known for months or years, authorities said Sunday. The Allegheny County Fire Marshal is leading the investigation, Allegheny County Executive Rich Fitzgerald said.

Authorities were encouraging people to stay away from the area unless they live there.

Related:

• 5 dead, including 1 child, in Plum house explosion
• Remembering father and son who died in Plum explosion: Casey and Keegan Clontz 'loved by so many'
• 'A humbling responsibility': Rustic Ridge's Greg Renko leads neighbors through tragedy
• 'We're so lucky': Family forced from home after Plum explosion grateful to be alive
• Outpouring of support for victims of Plum house explosion

The explosion at 141 Rustic Ridge Drive, reported around 10:22 a.m. Saturday, triggered an equally massive emergency response from the immediate area and beyond. Of the firefighters responding, Imbarlina said medics treated 57 at the scene for various minor issues. All returned to duty.

“The help we had and the response we had was unbelievable,” Plum Council President Mike Doyle said during the news conference.

A tally of the total number of homes affected by the blast was not available Sunday, Doyle said.

“With an explosion like that, there’s bound to be other collateral damage,” he said. “I was walking away yesterday and I saw a Jeep with the back window blown out. It’s not just houses.”

Natural gas and electric service were shut off to the bulk of the Rustic Ridge community yesterday “out of an abundance of caution,” Imbarlina said. A plan was in place to restore some of those services, with electric restored Sunday afternoon except to addresses directly affected by the blast — 135 to 145 on the odd side of Rustic Ridge, and 138-142 on the even side.

Michael Huwar, president of Peoples Gas, said its crews were on site by 10:50 a.m. Saturday and gas was turned off by 11:30 a.m. They immediately began checks in the area for leaks, including smell checks and testing for gas underground and in the air. They also verified consistent pressure at regulation stations, he said.

“At this point, we can share that our system was operating as designed,” Huwar said. “It’s still too soon to estimate when service will be restored.”

Huwar said they are helping the Allegheny County Fire Marshal in the investigation. “They are in charge, including additional testing of our system,” he said.

Peoples and the state Public Utility Commission were working with local officials on a plan for restoring gas service.

Huwar said the company will post information on its website and communicate directly with affected customers.

“At Peoples, our hearts are with the loved ones and those who have lost their life in this tragic incident,” Huwar said.

Imbarlina said the county fire marshal’s office is beginning its investigation of the cause and origin “in earnest.”

“Please understand that this will be a slow and long process as things need to be tested and there will be lots of forensic testing to be able to prove anything one way or another,” he said. “This investigation may last for months if not years. It’s a slow process.”

The municipal center and the nearby Renton fire hall on Old Mine Road are open as respite centers. Imbarlina said anyone who needs anything, including someone to talk with, can call a county help line at 800-985-5990 or text “talk with us” to 66746.

The Plum School District announced that its crisis intervention team will be available from 10 a.m. to 2 p.m. Monday and Tuesday at Plum Senior High School’s library.

Fitzgerald pledged the county’s support and thanked those who came to help from outside Plum and outside the county.

“It shows what people in southwestern Pennsylvania do when there’s these type of incidents,” he said. “People come together.”

Doyle said the outpouring of support that Plum has received from across the state and nation has been overwhelming.

“Our hearts go out to all the victims. This is still going to be a pretty long haul,” he said. “I can’t be more proud of this community. I just wanted to make sure that our first responders, everybody that showed up, is thanked properly. They were just absolutely world class.”

The borough announced that food, charging stations and other amenities would be available at its new municipal complex on Old Mine Road.

At the municipal center, Boy Scouts and Cub Scouts with Troop 111 were grilling hamburgers and hot dogs for residents and first responders. The food came from an event that was canceled Saturday because of the stormy weather, said Jim Plutto, a committee chair with the troop.

Plutto said one of the troop’s families lives in the Rustic Ridge neighborhood.

“We mobilized as soon as we heard,” he said. “What can we do? Where can we help? That’s the basis of scouting.”

The borough announced that all events scheduled for Monday have been canceled. Those include the Monday Market as well as a council meeting and public hearing scheduled for Monday night.