President Donald Trump is fulfilling his vow to drain the swamp — if climate scientists and environmental regulators qualify as swamp dwellers.

His proposed budget for the next fiscal year, released Thursday morning, would drastically slash the Environmental Protection Agency, eliminating 50 programs and 3,200 positions. Of all Cabinet-level agencies, the EPA would be hit with the largest budget reduction at 31 percent.

The downsizing is even more extreme than it appears because it comes on the heels of severe budget cuts that followed the Republican takeover of Congress in 2010 and the budget sequestration deal of 2011. The EPA’s budget of $8.2 billion this year was already down by more than 20 percent from $10.3 billion in 2010. It’s smaller today than it was in 2004 — and that’s without adjusting for inflation.

The cuts are also concentrated on EPA’s in-house programs rather than on the big chunk of its funding that is doled out to state, local, and tribal governments. Those state and local “revolving funds” from the EPA are for relatively uncontroversial programs like investing in clean water and sewer infrastructure — programs that make constituents back home happy. Trump’s plan doesn’t touch that $2.3 billion chunk.

Instead, he cuts 31 percent from the remaining share of EPA’s budget, which includes programs that study pollution and environmental toxins, and write and enforce rules to protect public health; altogether, those programs in particular will see a 42 percent cut. Clean air, clean water, and climate change programs would bear the brunt.

“When you consider that some of the money has to go to overhead and can’t necessarily be reduced — things like renting office space and support staff — the cuts to people like scientists, economists, attorneys, and contractors who write and enforce federal protections are even steeper than 42 percent,” said John Walke, director of the Clean Air Project at the Natural Resources Defense Council.

“What they’re trying to do is eviscerate the agency,” said Christine Todd Whitman, EPA administrator during George W. Bush’s first term.

A few notable cuts in Trump’s proposed budget:

The Clean Power Plan, which Trump has pledged to repeal, would be stripped of all funding for implementation. The rule, which would reduce carbon pollution from power plants, is the first carbon regulation in U.S. history and the centerpiece of the country’s commitment to reduce emissions in the Paris climate agreement. Eliminating it would be subject to court challenge. Defunding it, however, would effectively kill it without that threat.

The agency’s Office of Enforcement would be cut by 23 percent. “Those are the cops on the beat that you desperately need,” said Liz Perera, the Sierra Club’s climate policy director. She says that due to state and federal budget cuts in recent years, people often already wait weeks for inspectors to respond to complaints about pollution violations.

EPA’s Office of Research and Development would be cut in half, crippling things like the study of the little-understood health effects of fracking and new chemicals.

Superfund, which cleans up toxic sites, would lose 34 percent of its funding. “Those projects will be stalled, or they could be cleaned up poorly,” Perera said.

“We understand the administration has a different policy view on climate change, but this goes way beyond climate,” said Janet McCabe, the head of the EPA’s Office of Air & Radiation under Barack Obama. “This will affect the agency’s ability to respond to emergencies and to enforce environmental regulations that have been on the books for years.”

Related agencies that deal with energy and the environment are also on the chopping block. The Chemical Safety Board, for example, is targeted for elimination. Conservation programs in the Department of the Interior will face steep cuts; the National Forest Service would be sliced by 20 percent, which environmental experts predict will endanger watersheds.

At the Department of Energy, clean energy research programs like Advanced Research Projects Agency-Energy (ARPA-E), which is modeled on the Pentagon’s DARPA program that helped invent the Internet, are being eliminated.

“[Energy conservation] has bipartisan support, but for some reason, maybe because they want to support the fossil fuel industry, they want to eliminate it,” said Alex Taurel, deputy legislative director at the League of Conservation Voters. Other energy-efficiency efforts that have saved consumers money on their electricity bills are also zeroed out.

And that’s where Trump’s budget will collide with political reality. Some Republicans in Congress, and many of their voters, don’t oppose energy efficiency, clean energy research, or removing toxins from the soil.

Trump’s proposed cuts at EPA would offset only a fraction of his proposed increase in defense spending and his upper-income tax cuts. But they would succeed in effectively repealing laws like the Clean Air Act, Clean Water Act, and Toxic Substances Act by eliminating or kneecapping their enforcement. As Perera notes, there’s no point to environmental laws if they’re unenforceable.

Whitman predicts that Republicans will face a backlash if the cuts are enacted.