The Senate on Thursday approved an effort to overturn an Environmental Protection Agency rule tied to the Clean Air Act and designed to limit seven of the most hazardous air pollutants that are emitted by heavy industry.
The 52-46 party-line vote marked the first time in the 55-year history of the Clean Air Act that Congress has moved to weaken the power of the landmark environmental law.
Senate Republicans utilized the Congressional Review Act to overturn the regulation, which was passed by the Biden administration in 2024.
The joint resolution now goes to the Republican-led House, where it also expected to pass.
The rule tied to the Clean Air Act was finalized last year to close a loophole that required all “major” sources of seven hazardous air pollutants to reduce their emissions by the maximum achievable amount, a policy called “Once in, Always In.”
The rule requires that industrial facilities — often chemical plants, oil refineries, and other industrial factories classified as “major” sources of toxic air pollution — always maintain strict pollution controls. Even if they comply and limit those pollution levels, those facilities would always be labeled “major” sources under the rule.
The Trump Administration had killed the rule in President Trump’s first term, but the EPA, under former President Joe Biden, finalized and updated it last September. The environmental advocacy group Earthjustice has said that the rule forced 1,800 facilities across the country to tighten air pollution controls to comply with the law.
The seven pollutants in question are:
- Alkylated lead compounds
- Polycyclic organic matter (POM)
- Mercury
- Hexachlorobenzene
- Polychlorinated biphenyls(PCB)
- 2,3,7,8-tetrachlorodibenzofurans (TCDF)
- 2,3,7,8-tetrachlorodibenzo-p-dioxin
Several Republican lawmakers have been attempting to revoke the rule. Republican Sen. John Curtis of Utah introduced the resolution which passed Thursday. Curtis had argued that the rule disincentivized companies to deploy new technology to reduce pollution.
“The rule put forward under the former administration shut the door on progress,” Curtis said in a statement after the resolution’s passage. “It told companies that no matter how much they invest to reduce harmful emissions, they would still be punished with permanent red tape. That’s not good science, it’s not good governance, and it certainly isn’t good for the environment. My resolution restores a common-sense incentive: if you clean up, you get credit for it.”
Several environmental groups, however, blasted the move.
“Today, I worry for children’s health more than ever before,” Melody Reis, director of federal policy for Mom’s Clean Air Force, said in a statement to CBS News. “Just now Senate Republicans voted to hand a couple of thousand of the nation’s largest industrial polluters an easy way to release toxic air pollutants linked to cancer, birth defects, and brain damage. They voted to allow chemical manufacturers, pesticide makers, refineries and other facilities to turn off their pollution controls for the most insidious air pollutants known to humankind — chemicals such as dioxins, mercury, and PCBs. This will put our children, and all of us, at grave risk. It is a shameful, and completely unnecessary move.”
Michelle Roos, executive director of the Environmental Protection Network, which is made up of former EPA staffers, said in his own statement, “Congress should be strengthening EPA’s ability to protect the public from mercury, benzene, and other dangerous emissions, not stripping away rules that hold polluters accountable.”
The vote marks a major victory for the fossil fuel and petrochemical industries, which had lobbied against the “Once in, Always In” rule for some time. The National Association of Manufacturers, a trade group, sent a letter to Mr. Trump after his inauguration calling the rule “burdensome,” and listing it as one of several environmental regulations that are “strangling our economy” and should be reversed.
Since January, the Trump administration has undertaken a series of efforts to weaken the EPA through deregulation and staffing reductions.
In an interview with “Face the Nation” last week, EPA Administrator Lee Zeldin argued the rollbacks won’t have adverse impacts on health or the environment.
