Home that exploded in Plum mining town had ‘hot water tank issues’, fire investigators claim – as they continue to piece together what caused the destruction and three more victims are identified

The house at the center of a mysterious explosion that killed five people in the Pennsylvania mining town of Plum had “hot water tank problems,” fire investigators said.

Three buildings were destroyed by the blast just before 10:30 a.m. Saturday in the city, which is about 20 miles east of Pittsburgh, while dozens of other buildings were damaged.

Terrifying footage showed the moment when the house at 141 Rustic Ridge Road completely blew apart, engulfing other properties in flames.

The house was owned by Heather Oravitz, 51, the city’s community development director, and her husband.

Casey Clontz, 38, was named as a victim along with his 12-year-old son Keegan. On Tuesday, Plum Mayor Harry Schlegel confirmed the other three as Oravitz, Plum Borough Manager Michael Thomas, 57, and Kevin Sebunia, 55.

Oravitz’s husband, Paul, suffered severe burns over most of his body and remained hospitalized in critical condition on Tuesday, Schlegel said.

Two more people injured in the blast were treated in a hospital and released.

New doorbell footage shows the moment the house blew apart, causing extensive damage.

The images start with a calm, sunny shot of the street, with no signs of movement.

Moments later, the force of the blast shakes the camera violently and the debris is launched across the street, before falling to the ground as rain.

The former victim, Casey Clontz, is survived by his wife Jen and daughter Addie, 10.

The family said in a tribute to them, “Their smiles and laughter filled the hearts of their family and friends with joy that can never be replaced.”

Relatives have not said why the father and son were on the Oratvitz estate, but explained that it was not uncommon for them to drop by because they were “very friendly” with neighbours.

Public records show that Paul Oravitz, 56, his wife Heather, 51, and their two children, Taylor and Cole, lived at the property.

Sebunia was described as a devoted family man who leaves behind his wife, Kelly, and daughters, Emily and Abigail, according to the local newspaper Tribe Live.

“His family came above everything else,” his friend Joe Pulcini told the newspaper. “His two girls came before anything.”

Borough manager Michael Thomas is survived by his wife Jackie and their 16-year-old daughter, Tribe Live said.

The mayor told the newspaper that Thomas had recently taught his daughter how to drive a gearshift and described him as “probably the best neighborhood manager we’ve had.”

“He was a true professional and I considered him a friend. He ran the district and ran it well,” Schlegel said.

Emergency services said people were trapped under the rubble when they arrived at the scene.

County spokesman Amie Downs said the blast flattened one house and set two others on fire.

Fifty-seven firefighters were treated at the scene for minor problems, an Allegheny County official said.

The cause of the explosion is being investigated by the Allegheny County Fire Department’s office along with local law enforcement officials, with officials warning that the process will be diligent and will take time.

The fire chief’s office said in a statement Monday that it was aware of the reported problems with the hot water tank. The agency planned to investigate the cause of the explosion, with the hot water tank problem in mind, and “along with all other possibilities,” the statement said.

The Pittsburgh Post-Gazette reported that the development is on abandoned mining land surrounded by shallow still-producing or abandoned oil and gas wells.

Two producing gas wells are within about 1,000 feet of the house that exploded and a pipeline runs behind the development, but none of those structures have been identified as involved in the blast, the paper reported.

Michael Huwar, president of Peoples Gas, said official audits by the company showed that “our system worked as designed.”

The state’s public utility commission said Tuesday it is overseeing the utility’s integrity testing of nearby lines and interviewing utility workers, first responders and residents, and is coordinating on-site evidence collection “including natural gas service lines and meters.”

Commission safety engineers also oversaw the restoration of electrical service and the planning and safe restoration of natural gas service.

A spokesman for the county said on Tuesday that electricity had been restored to all but the three houses that were destroyed by Sunday afternoon.