Trump Is Trying Again to Gut Pollution Rules for Power Plants. We’re Fighting Back.

For decades, U.S. coal and oil plants largely avoided limits on how much hazardous air pollution they could emit. That changed in 2012 when a set of federal rules called the Mercury and Air Toxics Standards (MATS) went into effect, and a wave of coal plant closures followed across the country. By the EPA’s own calculations, these rules save as many as 11,000 lives a year.

Now, however, that progress is in jeopardy. The Trump administration is trying to dismantle MATS. It just repealed provisions of the rule that account for $33 million in annual health benefits. And it’s not the first time Trump has gone after these rules: We sued his first administration for trying to gut them in 2020.

Earthjustice will not allow Trump to take us back to an era when coal plants pumped out enormous amounts of toxic air pollution. We are already fighting his administration in court over air pollution exemptions granted to nearly a third of coal plants last year. We are prepared to use the full power of the law to defend the MATS regulations.

Why do the MATS rules matter?

• Initially established in late 2012 after decades of litigation and advocacy by Earthjustice and others, MATS became the first set of federal regulations to:
  • Limit mercury and other air toxics emitted by power plants
  • Require meaningful reductions of pollution from many older coal plants that had been allowed to dodge pollution control requirements for decades
• These regulations proved extraordinarily effective, cutting mercury emissions from coal plants by 90%, emissions of other metals by 80%, and helping save up to 11,000 lives each year.
• But the 2012 standards still left serious gaps. In 2024, the EPA under the Biden administration strengthened MATS to include:
  • Instituted continuous emissions monitoring, which shows communities how much pollution is coming out of the power plants in their neighborhoods and whether those facilities follow the law
  • Stricter pollution limits for particulate matter and mercury that will require the dirtiest plants, which account for a disproportionate amount of power plants’ toxic pollution, to reduce their emissions

What is the Trump administration doing to MATS?

• The Trump administration repealed the MATS rules enacted in 2024.
• The EPA’s own analysis of the 2024 rules found that they would have minimal impact on electricity reliability.
• This is only the administration’s latest move in a yearlong effort to help coal plants pollute with impunity:
  • In March 2025, EPA Administrator Lee Zeldin invited corporations to email the agency to request exemptions from clean air standards. Corporations were told they could cite “national security” or “lack of available technology” as justifications.
  • A month later, and again in July, President Trump issued a presidential proclamation exempting nearly a third of coal plants from complying with the strengthened MATS rules for two years.
  • The exemptions allow 71 coal power plants to release more mercury, arsenic, and other heavy metals known to damage children’s brain development, trigger asthma attacks, and cause cancer.
  • Epidemiological researchers quantified the public health impacts of these exemptions in a study published in October 2025, finding they would lead to the emission of an additional 2,500 tons of the toxic pollutant particulate matter 2.5 (PM2.5) and an estimated 32 preventable deaths.

How is Earthjustice fighting back?

• Earthjustice helped to enact the original MATS rules, suing both the Bush and Obama administrations for failing to protect our health from mercury and hazardous air pollution. We’ve fought to defend and strengthen these rules at every step since.
• Last June, we sued the administration over the MATS exemptions it had granted to the 71 coal plants. We are representing a coalition of community and environmental groups in our lawsuit, alleging that EPA solicited these exemptions by email, therefore sidestepping any form of public process and undermining Section 112(i)(4) of the Clean Air Act.