The Environmental Protection Agency has drafted a proposal to reverse a landmark scientific finding that planet-warming pollution from fossil fuels endangers human health, and could release that proposal as soon as this week, according to three people familiar with the plan.

Known as the “endangerment finding,” the 2009 declaration has served as the basis for federal rules limiting greenhouse gas pollution from power plants, cars and trucks, and the oil and gas industry. The repeal, if successful, would take away the federal government’s main way to fight climate change.

EPA administrator Lee Zeldin announced in March the agency would reconsider the rule as part of a suite of proposals to overturn pollution rules the Trump administration considers to be burdensome to the fossil fuel and transportation industries. A proposal to “update” the finding was first touted by Project 2025, the Heritage Foundation blueprint to overhaul the federal government and repeal many keystone regulations that have come to define life in modern America.

An EPA spokesperson did not comment on when the proposed rule would be released.

“The proposal will be published for public notice and comment once it has completed interagency review and been signed by the Administrator,” the EPA spokesperson said in a statement.

Environmental groups who have attended public meetings about the EPA’s proposal have been alarmed at the lack of EPA staff in those meetings. Only one White House Office of Management and Budget staffer has attended the public meetings with stakeholders, a highly unusual move, said David Doniger, a senior federal strategist at the Natural Resources Defense Council, and Shaun Goho, the legal director for the Clean Air Task Force.

“There was only one participant on the government side, and there was nobody from EPA,” Goho told CNN. “In my many years of experience doing these meetings, that is unprecedented. It raises questions about the role of EPA staff in this rulemaking. It raises questions about who is actually doing the work.”

The EPA spokesperson did not answer CNN’s questions about which agency is leading the rulemaking process.

The draft, titled “Reconsideration of 2009 Endangerment Finding and Greenhouse Gas Vehicle Standards,” was sent to the White House Office of Management and Budget on June 30, the EPA spokesperson said.

It is widely expected the proposal will also seek to repeal rules that regulate greenhouse gas emissions from vehicles, since they stem from the finding, sources told CNN. The Biden EPA sought to tighten those standards to prod the auto industry to make more fuel-efficient hybrids and electric vehicles.

CNN’s sources said the EPA proposal is still in draft form, and could still change before its release.

“We’re expecting that they will repeal all of the climate related vehicles standards, saying the predicate finding of danger wasn’t made right or doesn’t exist,” Doniger told CNN.

The EPA appears to be making a legal argument in the draft that the agency went beyond its legal authority to use the Clean Air Act to regulate pollutants that contribute to climate change, rather than trying to make a scientific argument that climate change itself isn’t harming humans, sources told CNN.

The EPA plans to argue the Biden vehicle rule presented harm to public health by increasing vehicle prices, decreasing consumer choice, and slowing the replacement of older vehicles, according to one person with knowledge of the draft.

“Legally, it’s misguided and creates enormous harms to the American people,” said Richard Revesz, a former Biden White House official and New York University environmental law school professor.

Doniger said the effort inside the administration has been helmed by political staff including Jeffrey Clark, who heads the Office of Information and Regulatory Affairs, the White House office that reviews regulations. Clark is the former Justice Department official who was investigated for aiding President Donald Trump’s efforts to overturn the 2020 election.

Clark served as assistant attorney general for DOJ’s Environment and Natural Resources Division in the first Trump administration and worked in the same office during the first George W. Bush administration.

“He’s been on a crusade to block EPA regulation of greenhouse gases under the Clean Air Act since then,” Doniger said.

Doniger said the agency’s proposed rule ignores the current reality of climate change, which is supercharging rainfall and leading to record global temperatures.

“For the administration to stand up and say in effect climate change isn’t happening or there’s nothing significant going on, so there’s no need for government standards, this is mindbogglingly out of touch with reality,” Doniger said.