Trump’s EPA Rollbacks Will Reverberate for ‘Decades’

US President Donald Trump is shrinking the Environmental Protection Agency more quickly and aggressively than ever before, culminating in this week’s move to rescind the crucial “endangerment finding” underpinning key regulations of planet-warming pollution.

And unlike Trump’s first term, the latest changes may be harder to reverse and result in long-lasting impacts on public health and the economy. Over the past year, the EPA has surpassed the staff and program cuts made during a similar period last time. It has also launched more pollution control rollbacks, with EPA Administrator Lee Zeldin proudly boasting about “the greatest day of deregulation our nation has seen.”

The EPA has been able to make such quick work this time around because it’s breaking historical precedent and testing the legal boundaries of administrative and environmental laws, according to interviews with more than a dozen current and former EPA staffers, advocates, historians, scientists and legal experts.

Rescinding the endangerment finding is the most consequential change for an EPA that’s been reoriented around sweeping deregulation. It marks the reversal of a key scientific determination — that greenhouse gases are harmful — supporting a swath of federal climate policy to curb emissions from vehicles and industrial sources. The previous Trump administration had planned a public debate of climate science, at the time considered the first step in challenging the finding, but abandoned the effort before it officially began.

The move is expected to immediately face legal challenges. That’s the point, said Joseph Goffman, assistant administrator of the EPA’s Office of Air and Radiation under President Joe Biden. The administration wants to get the issue before the Supreme Court, hoping its conservative majority bucks precedent in upholding the repeal, he said. If that happens, the agency would be severely restricted from enacting climate rules long after Trump leaves office, placing the onus on Congress if the US is to pursue pollution reductions.

So far, the EPA’s legal track record is mixed. While a court order forced it to reverse course on firing some employees early last year, it has also had some legal wins, including an appeals court recently upholding the agency’s cancellation of billions in climate grants. As the agency races to finalize more regulations and policy changes, more lawsuits are expected.

The EPA argues that these changes are necessary for right-sizing the government, which it says overstepped its authority under previous administrations, hurting the economy.

“Under President Trump, the EPA is proving what previous administrations refused to accept, that we can protect the environment” and grow the economy, said EPA Press Secretary Brigit Hirsch. “We are delivering cleaner air, land, and water while driving economic expansion.”

Many companies have welcomed the deregulatory push. Some of the nation’s largest refineries, petrochemical facilities and power plants, for example, took the EPA up on its offer to apply for presidential exemptions from various Biden-era air pollution rules.

But some industries have occasionally pushed back. The Edison Electric Institute, an association of investor-owned power companies, wrote in a public comment that ending federal regulation of greenhouse gas pollution from power plants could stall growth just as the industry is expanding to accommodate artificial intelligence’s electricity needs and update the grid. It could lead to balkanized state-level regulations, lawsuits and longer, less-predictable permitting, financing and construction, the group argued.

Former EPA officials, meanwhile, warn that the Trump administration’s changes are boosting pollution and could exacerbate health conditions such as asthma, cardiovascular disease and neurological development issues. In the long-term, they have the potential to cripple an agency created more than 50 years ago by then-President Richard Nixon to protect the environment and human health.

“It’s mind-boggling to me how an agency set up by a Republican administration, supported by bipartisanship all the way through, has now become kind of the enemy of the environment,” said Christine Todd Whitman, EPA administrator under President George W Bush and the former Republican governor of New Jersey. “That’s a scary thing because it takes a long time to get back.”

On Thursday, the EPA also ended emissions standards for automobiles, which were justified by the endangerment finding. The transportation sector accounts for 28% of US emissions, making it the largest source.

According to tracking by Columbia University researchers, the EPA has already taken more than 40 deregulatory actions since Trump came to power a second time, compared with almost 60 across the whole four years during his first term.

“Getting these really big ticket items done early on in administration is very problematic for whoever comes next,” said Romany Webb, deputy director of Columbia University’s Sabin Center for Climate Change Law. Actions taken “later in a presidential administration can be more easily reversed.”

A new set of tactics

EPA officials are deploying tactics that ensure their changes are more difficult to overturn, or can be rolled out faster.

For example, the Trump administration has enlisted the help of other branches of government. In his prior term, the EPA revoked California’s authority to set stricter vehicle emissions standards, which the Biden administration reinstated. This time, the EPA asked Congress to intervene. When California tried to impose stricter vehicle emission standards anyway, the Trump administration took the issue to court and won a temporary injunction blocking the state efforts as the lawsuit proceeds.

The agency has also found ways to quickly remake policy while sidestepping the formal rulemaking process. In 2020, it finalized a new rule to change how it measured costs and benefits from pollution-cutting rules. Biden reversed it. In January, the EPA took a different, faster approach by simply starting to zero out the monetary value of public health benefits from cutting two key air pollutants in its analyses — “actions that go way beyond” the 2020 rule, said Bryan Hubbell, a senior fellow at the economics think tank Resources for the Future.

In some cases, the policy changes themselves might be easy to reverse, but the emissions they cause will linger for decades in the atmosphere. For example, Trump bypassed the bureaucratic hassle of rolling back certain Biden-era rules by issuing presidential waivers granting polluters two-year exemptions. It’s a sweeping use of executive power that ex-EPA officials say they’ve never seen before.

At the same time, the EPA is pushing back compliance deadlines for other Biden rules. For example, it’s given oil and gas companies more time to fix leaky equipment and coal plants more time to cut their waste. A similar proposal to push deadlines for curbing highly potent greenhouse gases used in refrigerators and air conditioners is still under review.

These delays result in prolonging pollution that was on its way out, said Elizabeth Southerland, a former top EPA water official who resigned under Trump’s first term. US greenhouse gas emissions jumped in 2025, reversing two previous years of decline, according to an estimate by the research firm Rhodium Group. That’s due in part to increased coal production, which the Trump administration has facilitated.

EPA alumni working at the Environmental Protection Network released a report in 2024 estimating various Biden-era air rules would avoid over 100 million asthma attacks through 2050, meaning fewer missed days of school and work. With Trump exempting companies from some of these standards, Southerland said, “we will no longer have that enormous asthma benefit.”

Lost knowledge

As the EPA has pulled back on regulations, it has also restricted publicly available environmental information.

Last February, the EPA took down EJScreen, a free online mapping tool of environmental hazards, and removed a database of corporate risk-management plans put online by the Biden administration that lists the dangerous materials they store and what they’ll do if there’s an accident. The agency says the latter information is still available for in-person viewing and accessible through Freedom of Information Act requests.

If people don’t know where pollution is occurring, they can’t effectively organize to protect themselves. “Removing this information from public access puts communities at significant risk,” said Gretchen Gehrke, who tracks federal website changes for the research collaborative Environmental Data and Governance Initiative. There are decades of examples of accidental releases of harmful substances that have killed workers and neighboring community members, she added.

While the Trump administration’s swift and strategic dismantling of the EPA’s power has been troubling, current and former staffers say it’s the rapid loss of staff that will be felt the longest.

Over the first Trump administration, the EPA lost roughly 1,200 employees. It’s expecting to have lost more than 3,500 by September, EPA told Bloomberg News — more than 20% of the overall workforce. That’s due to a mix of layoffs, firing of whistleblowers, resignations and thousands of people taking incentive programs to voluntarily retire or leave early.

Many senior scientists, lawyers and other longtime employees have left, taking their institutional knowledge with them, said Justin Chen, president of the agency union American Federation of Government Employees Council 238.

“It’s going to take years, if not decades, to rebuild,” he added.

Photo: EPA Administrator Lee Zeldin has proudly boasted about “the greatest day of deregulation our nation has seen.” Photographer: Stefani Reynolds/Bloomberg

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