By MARC LEVY, GENE PUSKAR, MICHAEL CASEY and PATRICK WHITTLE
Associated Press

CLAIRTON, Pa. (AP) — After an explosion rocked a steel plant outside Pittsburgh, workers scrambled into the wreckage alongside firefighters. A cloud of black smoke rose above a charred pickup truck as rescuers sprayed the scene with streams of water.

By the time the scene was secure, two people were dead and more than 10 others were injured, including one who spent hours trapped in rubble left Monday by the blast that was powerful enough to shake nearby homes.

Video from Pittsburgh television station WTAE showed workers in orange jumpsuits and hard hats running toward the wreckage at the U.S. Steel coking plant in Clairton. A reporter described seeing someone being pulled from the debris and loaded onto a gurney. The station’s footage later showed a mountain of charred rubble spilling from a hole left by demolished walls.

Investigators worked Tuesday to determine the cause of the blast, which jolted a region of the state synonymous with steel for more than a century. The county medical examiner’s office identified one of the dead as Timothy Quinn, 39. A second worker was not identified, with his family requesting privacy.

County Executive Sara Innamorato told reporters she had assurances from U.S. Steel that the company would continue to cooperate fully with investigators.

“We all share a common goal. We want to get to the bottom of what happened, and we want to prevent it from happening ever again,” Innamorato said.

Democratic Gov. Josh Shapiro said steelworkers deserve “an answer for what happened. We owe them an answer to their questions, and we owe them for their sacrifices.”

Shapiro described Quinn as a devoted father of three who served as a mentor and leader to other workers. He was a second-generation steelworker, following in his father’s footsteps, and a “mama’s boy” who after working long shifts would take care of his mother and look after his children and his girlfriend’s two children.

“His life was cut too short because of what happened here at this plant,” Shapiro said.

Deanna Forkey was working behind the counter at the Hometown Burgers & Deli, which her family owns, near the plant when she heard the explosion. She said the restaurant door popped open.

“When I looked out, all you could see was black smoke,” she said. “Explosions over there aren’t really uncommon. We hear them a lot. But that one obviously was much worse.”

She said many plant workers are regulars at the restaurant.

“You start to build a little bit of a relationship," Forkey said. "So it kind of pulls a little harder at the heartstrings.”

Investigating the blast's cause

Speaking to reporters Monday, U.S. Steel’s chief manufacturing officer, Scott Buckiso, gave no details about the damage or casualties.

The Allegheny County Police Department said five people were hospitalized in critical but stable condition Monday night, and five others were treated and released. Other individuals were treated for injuries at the scene, but the department said it did not have an exact number.

According to the company, the plant has approximately 1,400 workers.

In a statement, the United Steelworkers union, which represents many of the Clairton plant’s workers, said it had representatives on the ground at the plant and would work to ensure there is a thorough investigation.

David Masur, executive director of PennEnvironment, an environmental group that has sued U.S. Steel over pollution, called for an independent investigation and a re-evaluation "as to whether the Clairton plant is fit to keep operating.”

It's not the first explosion at the plant. A maintenance worker was killed in a blast in September 2009. In July 2010, another explosion injured 14 employees and six contractors. According to online OSHA records of workplace fatalities, the last death at the plant was in 2014, when a worker was burned and died after falling into a trench.

After the 2010 explosion, the Occupational Safety and Health Administration fined U.S. Steel and a subcontractor $175,000 for safety violations. U.S. Steel appealed its citations and fines, which were later reduced under a settlement agreement.

In February, a problem with a battery at the plant led to a “buildup of combustible material” that ignited, causing an audible boom, officials said. Two workers received first aid treatment but were not seriously injured.

Pittsburgh attorney John Gismondi represented the widow of the worker who was killed in the 2009 explosion at the plant and three men who were badly burned in the 2010 explosion. In a phone interview Tuesday, Gismondi said his immediate thought a day earlier was “Oh my God, not again at Clairton.”

Both lawsuits were settled out of court for “significant” amounts, he said.

“There was no question in both of those cases we established that appropriate safety protocols weren’t followed, and that’s what led to the explosions,” he said. “There’s a lot of gas on the premises. That’s fine, it’s part and parcel of what they do. But gas is a dangerous substance, and you need to make sure safety protocols are being followed.”

In the 2010 case, Gismondi’s clients claimed managers directed them to repair a live gas line even after an alarm went off warning of high levels of natural gas.

Air quality concerns

The plant, a massive industrial facility along the Monongahela River, converts coal to coke, a key component in the steelmaking process. It 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.

The county health department initially told residents within 1 mile (1.6 kilometers) of the plant to remain indoors and close all windows and doors, but the agency lifted the advisory later Monday. Health officials said their monitors did not detect levels of soot or sulfur dioxide above federal standards.

The US Steel buyout

U.S. Steel, a symbol of industrialization since it was founded in 1901, has been the icon of the American steel industry that once dominated the world market. Japan and then China became preeminent steelmakers over the past 40 years. U.S. Steel recently became a subsidiary of Japan-based Nippon Steel Corp.

The deal, which was completed in June, came a year and a half after the Japanese company first proposed its nearly $15 billion buyout.

The pursuit of the Pittsburgh-based company was buffeted by national security concerns and presidential politics in a battleground state, dragging out the transaction for more than a year after U.S. Steel shareholders approved it.

Levy reported from Harrisburg, Pennsylvania. Casey reported from Boston, and Whittle reported from Portland, Maine. Associated Press reporters Holly Ramer in Concord, New Hampshire, Beatrice Dupuy in New York City and Audrey McAvoy in Honolulu contributed to this report.

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