Implementing Project 2025, the conservative manifesto written by ex-Trump officials, could have serious repercussions on public health, former Environmental Protection Agency employees warn.

Air quality protections issued over the past four years are supposed to cut down pollution and associated health risks, preventing premature deaths and hospital visits for years to come. A group called the Environmental Protection Network (EPN), created by hundreds of former EPA employees during an exodus of scientists from the agency under the Trump administration, counted up the benefits in a recent report.

But that outcome isn’t guaranteed. Many of the policies recently enacted under the Biden administration could be in jeopardy if Donald Trump is elected president again and ushers in another period of turmoil at the EPA. Project 2025, guided in part by alumni of the Trump administration, lays out a blueprint for drastically remaking the agency.

“Project 2025 is just full of recommendations that would essentially eviscerate EPA. They would turn it into a shell of what its true mission is,” says Stan Meiburg, executive director of the Sabin Center for Environment and Sustainability at Wake Forest University. Meiburg worked at the EPA for nearly four decades until 2017 when he left his post as acting deputy administrator and is now on the board of directors for EPN.

“From ambient [air quality] standards to regulations on greenhouse gas emissions from cars and from power plants — all of those are things that Project 2025 recommendations and the Trump administration in its previous iteration went right after,” Meiburg says.

Trump rolled back more than 100 environmental regulations during his single term in office. He appointed fossil fuel insiders to key posts within federal agencies, including the EPA, and attempted to slash the EPA’s budget. Amid the turmoil, 550 environmental protection specialists — one of every four — left the agency between 2016 and 2020.

The Biden administration has tried to reverse course, updating and issuing new policies to limit air pollutants and greenhouse gas emissions. Those policies could spur immense public health benefits if they survive past the presidential election in November, the EPN report forecasts.

The group analyzed the potential impact of 16 major air pollution rules issued since 2021, estimating that they could prevent 200,000 premature deaths and result in 100 million fewer asthma attacks in the US through 2050. Taking healthcare costs into consideration, the net annual benefits would add up to $250 billion through 2050, the report estimates.

“It’s hard to envision 200,000 people ... it’s equivalent to a convoy of buses stretching along the highway from Philadelphia to New York City. Think of the families waiting for those people to disembark,” says Jeremy Symons, an EPN senior advisor who coauthored the report and previously served as a climate policy advisor at the EPA before leaving in 2001.

The EPN’s estimates are limited to just 16 measures the EPA has taken to clean up the air — a fraction of the agency’s work considering the EPA is also tasked with preventing land and water pollution. Those policies range from stricter standards for cars and trucks and power plants to limiting emissions from oil and gas wells, appliances, and manufacturing.

Project 2025, crafted by the right-wing think tank Heritage Foundation, takes aim at some of those policies specifically. The EPA’s embattled Good Neighbor Plan, meant to keep smog-forming pollutants from upwind states from drifting toward its neighbors, is one example. Project 2025 says the next president should “review Biden-era regulations to ensure that they do not ‘overcontrol’ upwind states.”

The Supreme Court, with its three Trump-appointed members, has already dealt a blow to the Good Neighbor Plan. In June, SCOTUS granted Ohio, Indiana, West Virginia, and industry groups a temporary stay on the plan while they challenge the legal merit of the policy in court. A series of SCOTUS decisions since the Trump administration has propelled conservatives’ deregulatory agenda, making it trickier for the EPA to craft new regulations regardless of whoever is elected president next.

Vice President Kamala Harris says she’ll “tackle the climate crisis” and points to suits she filed against polluters as California’s attorney general, even though she has simultaneously touted record US oil production under Biden’s leadership. She’s expected to defend Biden era environmental policies like the Inflation Reduction Act, the largest spending package on clean energy ever passed in the US, from which Donald Trump said he would rescind funds. The sheer amount of funds the IRA tasks the EPA with spending or disbursing adds to its workload as it still recovers from the Trump-era brain drain.

Project 2025, meanwhile, pushes for a “major reorganization” at the EPA that would further reduce the number of full-time positions and eliminate entire departments and any programs deemed “duplicative, wasteful, or superfluous.” The lead author of the chapter dedicated to the EPA is Mandy Gunasekara, who was chief of staff at the EPA during the Trump administration. She served under Andrew Wheeler, a former coal lobbyist Trump tapped to lead the agency.

“The authors of the Project 2025 EPA chapter have used their years working at EPA under Trump as a scouting mission and a training ground for the even more reckless plans,” Symons says. “We’ve seen the impact that these kind of plans can have from President Trump’s term in office previously. We have to take it seriously when they set out to basically take EPA out of the game and hand the keys over to polluters.”

The Heritage Foundation didn’t immediately respond to a request for comment. The EPA didn’t comment on Project 2025, but spokesperson Remmington Belford said in an email that “EPA remains committed to protecting public health and the environment by implementing science-based pollution standards that address climate change and improve air quality for all Americans.”