WASHINGTON — The Trump administration next week plans to formally propose a vast overhaul of climate change regulations that would allow individual states to decide how, or even whether, to curb carbon dioxide emissions from coal plants, according to a summary of the plan and details provided by three people who have seen the full proposal.
The plan would also relax pollution rules for power plants that need upgrades. That, combined with allowing states to set their own rules, creates a serious risk that emissions, which had been falling, could start to rise again, according to environmentalists.
The proposal, which President Trump is expected to highlight Tuesday at a rally in West Virginia, amounts to the administration’s strongest and broadest effort yet to address what the president has long described as a regulatory “war on coal.” It would considerably weaken what is known as the Clean Power Plan, former President Barack Obama’s signature regulation for cutting planet-warming emissions at coal-fired plants.
That rule, crafted as the United States prepared to enter into the 2015 Paris Agreement on global warming, was the first federal carbon-pollution restriction for power plants. In 2016, the Supreme Court temporarily blocked the regulation from taking effect while a federal court heard arguments from a coalition of coal states that sued to block the rule. It remains suspended.
Now, the Trump administration wants to defang the Obama-era rule. The move follows a separate decision this month to freeze Obama-era fuel efficiency standards that were also aimed at reducing greenhouse gas emissions.
“These are the two biggest sectors of the economy that contribute to greenhouse gases in the country and are just hugely significant in terms of emissions,” said Janet McCabe, the Environmental Protection Agency air chief under Mr. Obama. Together the transportation sector and the power sector account for more than half of the country’s emissions, according to the agency.
“The science is just getting clearer and clearer every day,” Ms. McCabe said. “I don’t know how many times people need to hear that we’re having the warmest summer on record or how many storms people need to see. This is no fooling.”
Officials at the White House and the E.P.A. did not respond to requests for comment.
The plan is the latest move in a string of efforts — including prodding grid operators to purchase more electricity from coal plants and asserting that coal plant retirements are threatening the reliability of the national power grid — to end what Mr. Trump has called his predecessor’s war on coal and a sure sign to the industry that the Trump administration still has its back, even as coal production continues to decline.
Michelle Bloodworth, president of the American Coalition for Clean Coal Electricity, a trade group that represents coal producers, noted that 40 percent of the nation’s coal plants had either been retired or were scheduled to retire.
She put the blame for that on a mix of market conditions and what she called “very stringent” regulations under Mr. Obama. But, she said, efforts like Mr. Trump’s push to order grid operators to purchase electricity from struggling coal plants along with the new carbon regulations represent a welcome relief for the industry.
“I certainly think we are supportive of what the administration is doing and we applaud their efforts,” she said.
Conrad Schneider, advocacy director for the Clean Air Task Force, an environmental group, predicted that the new plan would ultimately make coal plants more competitive in the electricity markets, allowing them to displace cleaner sources of energy.
“Emissions are going to go up, and I don’t mean from where they would have been under the Clean Power Plan, but relative to the trends now,” Mr. Schneider said. “This is to put the thumb on the scales and bring coal back.”
The proposal could help Mr. Trump rally his base in coal regions heading into the midterm elections, though there are few vulnerable Republican seats in those areas and it could also involve political risk by pushing Democrats to the polls.
“Everyone who votes on climate change is a Democratic base,” said Eli Lehrer, president of R Street, a free-market think tank in Washington that supports policies to combat climate change but opposes the Clean Power Plan.
Under the Clean Power Plan, the Obama administration had sought to reduce the country’s greenhouse gas emissions from power plants 32 percent below 2005 levels by 2030. There is no mention of an overarching national goal for reductions in the new Trump proposal, which was described on the condition of anonymity. Instead the rule sets guidelines for states to develop and submit to the E.P.A. plans to establish “patterns of performance” for existing coal plants.
The options for achieving cuts would also be narrower. Under the Obama-era rules, states had broad latitude on how to meet their targets, ranging from building wind farms to switching from coal to natural gas. Now, reductions would be confined to measures coal plants can achieve on-site, like improving heat efficiency.
The United States has already achieved much of the reductions sought under the Clean Power Plan, and Allison D. Wood, a partner at the law firm Hunton Andrews Kurth who represents several electric utilities, said she believed the new proposal would provide utilities with certainty while still allowing emissions to dip.
“It may not look as stringent, but one of the important things to keep in mind is the emissions reductions that were driven by the Clean Power Plan were driven by forcing a move from coal to natural gas and renewables,” she said. “That’s happening anyway even in the absence of the Clean Power Plan.”
While offering a possible lifeline to the coal industry, the new rule is also notable for what it would not do: reject the federal government’s legal obligation to reduce emissions.
The plan barely takes note of climate change. The words appear on only one of the nearly 300 pages of documents, according to two of the people who have seen the full draft. Yet, by proposing the regulation at all, the Trump administration is implicitly acknowledging a key 2009 E.P.A. decision known as the endangerment finding that declares climate change a threat to human health and welfare.
That finding is the legal backbone for almost all federal climate policy and requires the government to regulate greenhouse gas emissions.