Industry groups had sued California over both of its rules, which had been pending at EPA for more than a year. California requires permission to enforce its stricter-than-federal rules under the Clean Air Act through a waiver system that has been in place since the 1960s. Acting Administrator Jane Nishida responded to CARB on Tuesday that the agency “considers this matter closed.” Randolph said the agency was “disappointed” that EPA couldn’t act on all of the requests and is “assessing its options” to continue progress on improving the state’s air quality.

California Gov. Gavin Newsom made approval of the state’s clean air waivers a top priority in recent months, including on a November trip to Washington D.C. shortly after the election where he lobbied EPA officials to approve the full suite of waivers. A planned return trip was nixed last week as wildfires burned in Los Angeles.

Newsom spokesperson Daniel Villasenor said in a statement Tuesday that the governor “is 100% focused on the Los Angeles fires.”

“We’re grateful to the Biden Administration for approving our six requests and we’ll continue to fight for clean air and water for all,” he said.

The Trump transition team didn’t immediately respond to requests for comment.

The CARB decision doesn’t affect other California regulations that are intended to tighten emissions from diesel-powered trucks and phase out fossil-fuel powered passenger car sales by the 2030s, which EPA approved in December.

The pair of rules could have saved more than $58 billion in health benefits like reduced heart attacks and asthma complications, according to a February report from the American Lung Association — more than four times the impact of the car mandate.

The Association of American Railroads, which represents companies like BNSF Railway and Union Pacific, and had sued CARB over its locomotive rule in 2023, cheered the move.

“Railroads are pleased that the California Air Resources Board has withdrawn its authorization request for the ill-conceived in-use locomotive rule,” AAR spokesperson Jessica Kahanek said in a statement. “As we move past this untenable proposal, railroads look forward to advancing their already strong sustainability profile and further reducing emissions in the years to come.”

Nebraska Attorney General Mike Hilgers, who is leading a lawsuit filed by 17 conservative states challenging the Advanced Clean Fleets rule, called the news a “win for the rule of law and freedom from unaccountable bureaucrats on both coasts.”

“California does not have the legal authority to force the rest of the country to transition to electric trucks,” Hilgers, a Republican, said in a statement. “California’s attempt to export its radical electric-truck mandate was unconstitutional, unlawful, and bad policy.”