The Environmental Protection Agency has proposed pulling back on fuel-efficiency standards for future model cars and trucks that the Obama administration put in place. (Julio Cortez/AP)

The tug of war over how much more fuel efficient new cars and trucks should be in coming years — a fight that once seemed all but settled — will play out again on Wednesday in a downtown Washington hotel.

The Environmental Protection Agency is holding an all-day hearing on its proposal to reconsider requirements that the U.S. car and light-truck fleet achieve an average 54.5 miles per gallon by 2025. The Obama administration had pushed for the standard as a key part of its efforts to scale back the nation’s greenhouse gas emissions.

In another sign that the Trump administration intends to chart a starkly different course on climate change, the EPA announced plans earlier this year to withdraw the Obama administration’s final decision on strict fuel-efficiency standards for future cars and light trucks.

That decision came shortly after two associations representing the world’s biggest automakers — the Alliance of Auto Manufacturers and the Association of Global Automakers — implored EPA Administrator Scott Pruitt to reconsider the standards for model years 2022 to 2025. In part, the industry has argued that it will be difficult to achieve the long-term targets set under the Obama administration, given persistently low gas prices and an abiding preference among many Americans for sport-utility vehicles.

Last month, the Trump administration gave notice that it planned to relax those requirements, saying that the EPA and the Transportation Department would consider revamping the future emissions standards. At the time, Pruitt promised “an open and robust review.” The move was the latest in a series of actions, such as the U.S. exit from the Paris climate accords and pushing to roll back regulations on coal-fired power plants, aimed at reversing Obama-era climate initiatives.

The agency is likely to get an earful on Wednesday from environmental and public health groups that oppose any effort to scale back requirements for automakers to build more fuel-efficient cars.

The Sierra Club has rallied supporters to show up to the hearing. Groups such as the American Lung Association, concerned about auto emissions’ effects on health, are sending speakers to urge against weakening the standards. The Environmental Defense Fund has called Pruitt’s action “a reckless U-turn” that ignores a rigorous body of scientific data and public input, and would ultimately harm consumers’ pocketbooks.

Margo Oge, a former director of the EPA’s Office of Transportation and Air Quality, noted that more than a dozen auto manufacturers publicly embraced the 2025 greenhouse gas standards at a White House event in 2011. She said many vehicles the industry produces already could meet the standards the Obama administration put in place.

“Some 25 percent of the vehicles today already meet future standards — while [companies are] recording record sales and profits — and yes, doing so selling a lot more efficient vehicles that have saved the consumer already billions,” Oge wrote in an email. She added that while more recently, automakers have argued that the standards cannot be met on time, she believes investors would reward any company “willing to break from the pack — for their courage, should they find it.”

But the auto industry has maintained that the EPA never conducted a full-fledged “midterm” review of the future standards, which it had committed to doing by 2018. As a result, the Alliance of Auto Manufacturers argued in a February letter to Pruitt that the emissions goals put in place by the Obama administration could cost the industry billions of dollars and drive up vehicle prices. “We urge EPA to reconsider such a far-reaching mandate on an entire industry without adequately considering the consequences, and without giving stakeholders a meaningful opportunity to comment,” the letter said.

Pruitt agreed.

So on Wednesday, the public will have a chance to argue all over again on how fuel efficient the country’s automobiles should have to be in the years ahead.

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