Nippon Steel plans no clean-fuel upgrades at three Mon Valley plants, residents say

Asthma rates triple near steel mills in Pennsylvania’s Mon Valley

Two days before Father’s Day this year, Trisha Quinn was wondering how her nieces and nephews would handle their first holiday without their father. Her brother, Timothy Quinn, 39, had worked at the Clairton Coke Works south of Pittsburgh for 18 years. He and colleague Steven Menefee were killed in an Aug. 11, 2025 explosion at the plant, one of the largest coke-making facilities in the western hemisphere.

“His girlfriend called me and said they couldn’t find him,” Quinn told The Guardian. “There was absolutely no communication [from the company]. We were calling all the local hospitals; I put myself on the news, to look for him. Then I got told to contact someone in the union. Then some ladies from the company came out to my mom’s house to share the news that he was deceased.”

Nippon Steel had acquired U.S. Steel for $14.9bn just months before the explosion. Quinn has since filed a wrongful death lawsuit against Nippon Steel and two other companies alleging negligence. Menefee’s family has also filed a lawsuit.

The U.S. Chemical Safety and Hazard Investigation Board found that the cast iron valve that failed during a cleaning operation was manufactured in 1953. In February, the U.S. Department of Labor cited U.S. Steel and contractor MPW Industrial Services Inc, fining them $118,214 and $61,473 respectively, finding that U.S. Steel “failed to use required safety management and energy control practices for hazardous work involving flammable gas.”

In response to the incident, a U.S. Steel spokesperson said the company has “strengthened several safety protocols based on the investigation results” and that employees have completed comprehensive training on new program elements and procedural changes. The company would not comment on whether it is compensating the families, but said it continues to cooperate with government agencies and holds the affected employees “in our thoughts.”

Despite pledging $11bn to upgrade the steel plants it acquired, Nippon Steel has made no effort to develop clean-fuel production at its three facilities in the Mon Valley, one of the most polluted regions in the U.S. for sulfur dioxide and hydrogen sulfide. Instead, the company plans to open a coal-free integrated steel mill in Arkansas. U.S. Steel says it aims to reach net zero by 2050.

In Braddock, a 14-mile drive down the Monongahela River from Clairton, US Steel announced this month that the 150-year-old Edgar Thomson Works would receive a new hot strip mill — a project locals say would increase air pollution. Nathan Mallory, a North Braddock councilmember and resident who lives within earshot of the plant, said he and other councilmembers claim they were pressured by US Steel to vote on a resolution allowing a new sewer connector for the plant without being informed of the full extent of the project.

More than 70% of Braddock’s population is Black, and the town’s per capita income is $15,500. Thousands of people live within a two-mile radius of the plant.

“There has been years and years of citations [for pollution and other issues] under US Steel; there is this notion that it’s cheaper for US Steel to pay the health department citations … than it is to put containment equipment, a technology that does exist, on the existing blast furnaces or to replace them with something cleaner,” Mallory said. “We’re just fodder to the industry.”

Matthew Mehalik, executive director of the Breathe Project, said the responsibility for worker deaths and community deaths from pollution-related disease “is rooted in US Steel’s dependence on coal-based technology, combined with a ‘drive it til the wheels fall off’ approach to managing this facility.” He said the only way to ensure a safer, cleaner future is to replace coal-based steelmaking equipment with clean, coal-free, next-generation technology.

Asthma rates among children who live close to the plants are triple the national rate, The Guardian reported. US Steel’s own reporting shows that the new hot strip mill would increase particle pollution by up to 40%.

The August explosion was not the only incident at Clairton last year. In February 2025, two workers were injured in another explosion at a smokestack. In 2009, a maintenance worker was killed following a gas leak. Less than a year later, 15 workers suffered severe burns in a coke oven explosion. After a 2018 fire, US Steel promised to spend $1bn across its three Mon Valley facilities to curb pollution, but shelved that plan within two years.

For the Quinn family, whose fathers and sons worked more than 60 years in the steel industry, the calculus has changed. “His son wanted to be a steel worker, but we said, ‘No, that’s not an option,’” Trisha Quinn said. “I don’t want to jeopardize his life.”