Moments after an explosion erupted at a U.S. Steel plant outside Pittsburgh, company firefighters, local responders and employees raced in to rescue people from the smoldering wreckage.
They were able to free one injured worker who was whisked to a hospital. But one more was still missing, and the area was too unstable to continue working, according to Matthew Brown, chief of Allegheny County Emergency Services.
A Pittsburgh-based crew from Pennsylvania Urban Search & Rescue was called in to help, some of whose members were already responding through their affiliations with local fire departments, Brown said. The team stabilized a wall at the plant and used an advanced camera to detect the missing employee. They pulled away the rubble and were able to extract the body of the worker, who died.
Monday’s explosion, which was powerful enough to shake nearby homes, killed two workers and injured more than 10 others. Five people ranging in age from 27 to 74 remained hospitalized Tuesday including the rescued worker, who was in critical but stable condition, according to the Allegheny County Police Department. Three were at UPMC Mercy, the region’s only level-one trauma and burn center.
The massive plant along the Monongahela River in Clairton converts coal to coke, a key component in the steelmaking process. The facility is considered the largest coking operation in North America and is one of four major U.S. Steel plants in Pennsylvania.
To make coke, coal is baked in special ovens for hours at high temperatures to remove impurities that could otherwise weaken steel. The process creates what’s known as coke gas — a lethal mix of methane, carbon dioxide and carbon monoxide.
U.S. Steel’s chief manufacturing officer, Scott Buckiso, said workers were conducting routine operations at the time of the accident.
Two loud booms that followed the initial blast were initially thought to be subsequent explosions, but Buckiso said they were from the activation of two relief pressure valves — a safety mechanism that operated as expected.
The cause of the explosion remained under investigation, and Democratic Gov. Josh Shapiro told reporters Tuesday that workers deserve an “answer for what happened.”
“We owe them the answers to their questions, and we owe them to never forget the sacrifices that occurred here yesterday,” Shapiro said. Before arriving at a news conference, he met with family members of a worker who died.
Allegheny County Executive Sara Innamorato told reporters she had assurances from U.S. Steel that it would continue to cooperate fully with investigators.