The 14-inch Twin Oaks Pipeline, owned by Energy Transfer, was hit Thursday by contract workers performing work for PECO. Fuel flowed across the ground and into the nearby Glasgow McCoy quarry, which sits less than half a mile from the Schuylkill River.

A Unified Command made up of the U.S. Environmental Protection Agency, the Pennsylvania Department of Environmental Protection and Energy Transfer said in a statement that there is "no impact to public drinking water sources or the Schuylkill River" at this time.

Air quality has been a central concern. Officials deployed 10 stationary monitors along the quarry's fenceline, four in the active work zone and 20 roving monitors through nearby neighborhoods. The devices measure flammable vapors, volatile organic compounds and benzene, a known carcinogen found in petroleum products.

According to Unified Command, monitors have "not detected any elevated levels" of volatile organic compounds in the community or at the fenceline, and readings in the work zone have stayed below levels of concern. No concerning VOC levels were found at the quarry or surrounding area.

Still, officials cautioned that shifting weather could carry fuel odors into neighborhoods. "Jet fuel has a distinct odor even at very low concentrations," the Unified Command statement said. "While this odor threshold concentration is not at levels that can harm your health, we recognize that the odors can still affect residents' quality of life."

Chris DiGiulio, director of environmental science and investigations for Physicians for Social Responsibility of Pennsylvania and a former analytic chemist at the U.S. Department of Defense, said she is particularly worried about fumes trapped inside homes. She noted that inhaling even small amounts of benzene can affect health.

"If you are smelling it, it is in your physiology," DiGiulio said. "The sensors [may not be] reading it, but if you can smell it, it could be impacting your health."

The federal Pipeline and Hazardous Materials Safety Administration has approved repairs to the pipeline and authorized it to return to service.

Crews have vacuumed fuel and water from the quarry into temporary storage tanks. Responders also laid sorbent boom and absorbent pads to capture pooled product from paved areas, stormwater ponds and other affected spots, and placed contaminated debris and sorbent in roll-off containers for testing and off-site disposal. Drones have been used to assess conditions at the quarry and along the Schuylkill River.

The incident has drawn sharp criticism from PECO's union leadership. Larry Anastasi, business manager for IBEW Local 614, said the utility gives contractors "vague work guidance" with little oversight, and he faulted upper-level management and consultants for decisions driven by profit and speed.

"We don't bake cupcakes. If you make a mistake here, it's catastrophic," Anastasi said.

Anastasi said he does not blame the workers from CJ Drilling, an Illinois-based contractor hired by PECO to build a transmission tower near the pipeline. But he argued that industry practice calls for local workers to be on site alongside contractors.

"If you're a contractor, you're on a time crunch. There's money on the line, the pressure is significantly larger," he said.

PECO said it "strongly reject[s] any suggestion that we would put schedules, cost, or any other consideration ahead of safety." The company said the workforce was "not a factor in determining what caused" the pipeline strike, and that the contractor was chosen for specialized expertise PECO does not hold internally.

"What is important now is establishing the facts," PECO said. "PECO will fully support the investigation and conduct a thorough review of the incident, including the processes and procedures associated with this work."

Pennsylvania's One Call law requires excavators to call 811 before digging and obligates pipeline operators to mark their lines. Digging within 18 inches of a marked pipeline is prohibited.

The Twin Oaks Pipeline was built in 1956 and carries refined petroleum products more than 100 miles from southeastern Delaware County to Newark, New Jersey. The same line leaked in Upper Makefield Township, Bucks County, in January 2025, spilling more than 6,000 gallons of jet fuel and contaminating private drinking water supplies. After that incident, the Pipeline and Hazardous Materials Safety Administration ordered Energy Transfer to inspect and, if needed, repair its pipelines after finding a "system-wide risk" of similar leaks.

Cleanup and monitoring at the Upper Merion site are expected to continue through the week.