DEP working with the Pennsylvania Public Utility Commission, local and county agencies

Plum, PA – Earlier this week, Governor Josh Shapiro directed the Pennsylvania Department of Environmental Protection (DEP) to launch an investigation into the house explosion in the Rustic Ridge neighborhood of Plum Borough, Allegheny County.

Under the Governor’s direction on Monday morning, August 14, 2023, in coordination with local and County authorities, DEP inspectors began conducting a stray gas investigation at the incident site to look for sources of combustible gas near the structure and inspecting nearby natural gas-related facilities and infrastructure under DEP’s jurisdiction.

DEP continues to work in cooperation with the Pennsylvania Public Utility Commission (PUC), Allegheny County Fire Marshal’s (ACFM) Office, utility operators, and other county and local emergency service agencies. The ACFM continues its investigation into the cause and origin.

“From the moment DEP was called in to investigate, our experts have worked tirelessly alongside county officials and partner agencies to aid in identifying the cause,” said DEP Secretary Rich Negrin. “Our emergency response team, geologists, and members of the Oil and Gas District Operations will continue to have boots on the ground in the days ahead, as we exhaust every relevant resource in our scope of jurisdiction.”

DEP inspectors are using handheld gas detectors to take daily readings for the presence and concentration of combustible gas – like methane – in the soil or in structures around Rustic Ridge. Where sufficient volume of gas is measured, inspectors are taking samples for lab analysis. DEP expects expedited results from the first samples collected. Potential methane sources include landfills, sewer lines, active/abandoned/historic oil or natural gas wells and associated pipelines, and coal mines. Analysis of the isotopic signature of the gas can indicate the depth of where the gas originated to aid in DEP’s identification of the source of the gas. 

DEP staff have already inspected the closest oil and gas well sites near Rustic Ridge and are coordinating with the owners/operators of the wells and associated pipelines. DEP staff have begun inspecting abandoned/historic wells and will continue to search for unregistered oil and gas wells in the area that may also be a source of natural gas. 

“I am in constant communication with Governor Shapiro, who has expressed his unwavering support for the Plum community and for the use of all available investigative measures. At the Governor’s request, an extensive amount of testing has been completed. I have ordered that the results be expedited. Over the next few days additional testing will be conducted and shared with the public appropriately,” added Negrin. “It is not lost on our agency the tremendous impact this event has had on the Plum community. Our thoughts and prayers remain with the family and the precious lives lost through this tragic incident.”

Media sources have noted the presence of abandoned mine lands in the area. Vast swaths of southwestern Pennsylvania sit atop abandoned underground mines. DEP has assessed the coal seam in the Plum Borough area and found no nearby shafts or drill/bore holes in the vicinity of the incident and determined the likelihood of an abandoned mine-related gas issue to be very low. Two DEP projects to extinguish the nearby Renton abandoned mine fire were successfully concluded in October 2021. Abandoned mine features are not currently part of DEP’s investigation.