The Allegheny Health Department has fined U.S. Steel $2 million for violating state laws on hydrogen sulfide emissions at its Clairton plant.
The county found the company’s Clairton coke works caused hydrogen sulfide levels at the nearby Liberty, Pa. air monitor to surpass state air quality standards a total of 159 times between March 2022 and November 2023. More than half of those exceedances were of “major severity,” where the level of hydrogen sulfide is at or above 8.25 parts per billion, or 65 percent over the state limit of 5 parts per billion.
Hydrogen sulfide is a byproduct of the coking process, in which coal is converted to coke, a key component of steelmaking. It is a colorless gas that gives off a rotten egg smell and can cause eye irritation, headaches, and fatigue.
Zachary Barber, clean air advocate for PennEnvironment, said the gas also affects human health.
“The pollution itself can be harmful. And it often is released in conjunction with other forms of pollution that can be harmful to health as well, including things that are known to trigger asthma attacks and carry other health risks,” he said.
History of violations
The county and federal EPA have fined the company nearly $12 million in the last two years for violating air pollution laws at its Pittsburgh-area plants. The Clairton plant, the largest producer of high-grade coke plant in the Western Hemisphere, is by far the largest single source of hydrogen sulfide emissions in the state, and responsible for over 90 percent of these emissions in Allegheny County, according to state data.
The county found the emissions come from several sources at the plant, including leaks of coke battery doors, water quenching of hot coke, the coke oven gas collection system, by-product plant sources, and other processes at the plant.
The county health department fined the company $1.8 million for similar violations in 2022 when it concluded a study finding high levels of hydrogen sulfide in the Monongahela River valley were “entirely” caused by the Clairton plant.
What’s next
Under county air rules, companies are not allowed to “cause an exceedance” of ambient air quality standards.
The county’s order includes a stipulation that the company develop a plan to fix its pollution problems.
“That hopefully helps set the stage for tackling this problem going forward and ensuring that it doesn’t just stop here with the fine and gives us a future tool for accountability,” Barber said.
A spokesperson for U.S. Steel said in a statement the company “attempted to work with” the county health department on the alleged violations, “but the Department unilaterally terminated those discussions.”
“U.S. Steel values our shared environment and the communities in which we operate, and we prefer to work with the Department collaboratively in these efforts,” the statement said.
A spokesperson for the county health department declined to comment, stating that the enforcement action filed by the county spoke for itself.
In December, Japan’s Nippon Steel announced it was buying US Steel for $15 billion, though that sale may face federal regulatory hurdles.
