Two killed and 10 injured after multiple explosions rock Pittsburgh area steel plant

Locals were told to close windows and doors following the explosion

Multiple explosions at a steel plant near Pittsburgh have killed two people and left 10 others injured on Monday, according to authorities.

Video captured a massive black plume of smoke rising from the U.S. Clairton Coke Works plant, 15 miles south of Pittsburgh, around 10:51 a.m. Monday. The Allegheny County Department of Emergency Services reported that a fire had broken out.

Ten people were transported to Allegheny Health Network hospitals. Five were in critical but stable condition and the rest have been released, The Washington Post reported.

Officials said at least two people were killed, according to the Post. One of those who died had been found in the rubble from the explosion and was taken to the hospital.

The plant was stable by Monday afternoon, said Scott Buckiso, executive vice president and chief manufacturing officer for U.S. Steel.

Authorities had declared a Level 3 Mass Casualty Incident, meaning the explosion required a large response from multiple neighboring agencies. Allegheny County Emergency Services Chief Matthew Brown said during a press conference that 20 EMS and 14 fire departments assisted.

An explosion at a steel plant outside of Pittsburgh, Pennsylvania, killed two people and left 10 others injured Monday morning. (WTAE)

Clairton Mayor Rich Lattanzi noted on social media that he was “asking for multiple ambulances” to be sent to the scene.

“My prayers go out to anyone involved in this tragedy and their families and the community,” Lattanzi said.

Pennsylvania Gov. Josh Shapiro said there were “multiple explosions” at the plant, and that his administration was working with local officials in Clairton on the response efforts.

Zachary Buday, a construction worker near the scene, told WTAE that the explosion sounded like thunder.

First responders were working to try to rescue people stuck under rubble following the explosion. (CMU CREATE Lab/ Breathe Project)

“It shook my chest. It shook the building, then we saw the dark smoke rising from the steel mill,” Buday said. “Put two and two together. It’s like something bad happened.”

Buday said he couldn’t see the fire that erupted from the plant, but saw the thick gray smoke clouding over the area.

“Lots of ambulances, lots of sirens. It sounded like thunder,” he added.

Allegheny County Health Department officials are monitoring air quality in the surrounding area but said monitors have not detected levels of soot or sulfur dioxide above federal standards. Residents within a mile of the steel plant have been told to close doors and windows, set HVAC systems to recirculate and avoid drawing outside air into homes, out of an abundance of caution, the county health department said.

U.S. Steel said the incident occurred “specifically at coke oven batteries 13 and 14” just after 10 a.m. Monday.

Clairton Mayor Rich Lattanzi noted on social media that he was “asking for multiple ambulances” to be sent to the scene . (AFP/Getty)

"Our top priority is the safety and well-being of our employees and the environment. We are working closely with relevant authorities to investigate the cause of the incident and will provide additional updates as they become available,” David B. Burritt, president and chief executive officer of the United States Steel Corporation said in a statement.

The United Steelworkers union had health and safety experts at the scene, a spokesperson said in a statement.

“The USW has occupational health and safety experts and other representatives on the ground at the Clairton Works assessing the situation and aiding our members,” said USW District 10 Director, Bernie Hall. “While we are still determining the scope of the tragedy, we are aware that multiple workers are receiving medical treatment for their injuries. In the coming days, we will work with the appropriate authorities to ensure a thorough investigation and to see that our members get the support they need.”

Ten people were rescued and taken to area hospitals to be treated for injuries. (CMU CREATE Lab/ Breathe Project)

The plant is considered the largest coking operation in North America. It employs thousands of workers. (US Steel Clairton Works)

The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) is responding to the explosion, the agency wrote on social media.

Allegheny county, which includes Pennsylvania's second largest city of Pittsburgh, is a longtime industrial hub once dominated by the steel industry. The plant, which sits along the Monongahela River, is considered the largest coking operation in North America.

Coking is the process of heating coal above 1,000 degrees, and is a critical component in the steel-making process. The plant produces 4.3 million tons of coke annually and employs 1,400 people, according to the company.

While U.S. Clairton Coke Works has kept many people employed and helped the local economy, the steel industry has dwindled in America for decades.

The industry took another turn when Pittsburgh-based U.S. Steel, once the leading steel-manufacturer, announced it would be sold to Nippon Steel, a Japanese steel company. Negotiations on the deal dragged on for over a year, but were approved in June after Nippon Steel agreed to allow the U.S. government to appoint a member to their board.

The Clarion plant has had a slew of issues over the years, including several lawsuits over pollution coming from the facility.

In 2019, it agreed to settle a 2017 lawsuit for $8.5 million. Under the settlement, the company agreed to spend $6.5 million to reduce soot emissions and noxious odors from the plant. The company also faced a lawsuit accusing them of violating clean air laws after a fire on Christmas in 2018 that damaged the facility’s sulfur pollution controls.

Pittsburgh-area U.S. Clairton Coke Works employs 1,400 people. (WTAE)

The damaged control equipment led to repeated releases of sulfur dioxide, according to the lawsuit. Sulfur dioxide is a colorless but pungent byproduct of fossil fuel combustion that can make it difficult to breathe. The fire also caused $40 million in damage.

Most recently, in February, a problem with a battery at the plant let to a “buildup of combustible material” that ignited and caused an audible “boom,” according to the Allegheny County Health Department.

Two workers who got material in their eyes were treated at local hospitals.

The company also agreed to spend $19.5 million on equipment upgrades and $5 million on local clean efforts last year as part of settling a federal lawsuit filed by Clean Air Council, Penn Environment and the Allegheny County Health Department.

With reporting by the Associated Press.