CARB drops EPA waiver request for in-use locomotive rule

The California Air Resources Board (CARB) has withdrawn its request for a waiver from the U.S. Environmental Protection Agency (EPA) that would have allowed the board to enforce its in-use locomotive rule.

In November 2023, CARB sought a waiver from the U.S. Clean Air Act so it could enforce a new rule that would prohibit certain older locomotives from operating in the state and require railroads to upgrade to cleaner units that produce less pollution. 

The railroad industry — through the efforts of the Association of American Railroads and American Short Line and Regional Railroad Association — had been fighting the rule in federal court. The associations argued that the rule would harm the U.S. economy, be so costly it could drive some smaller railroads out of business, and mandate the use of technology that isn't readily available.

CARB withdrew its application a week before the Trump administration takes over the EPA. In a Jan. 13 letter to EPA Acting Administrator Jane Nishida, CARB Executive Officer Steven Cliff asked that its waiver request, submitted in November 2023, be withdrawn. In a Jan. 14 response, Nishida said it would take no action on CARB's application and "considers this matter closed." 

 AAR officials said in an email that railroads are pleased CARB dropped its waiver request for an "ill-conceived" rule.

"As we move past this untenable proposal, railroads look forward to focusing on advancing their already strong sustainability profile and further reducing emissions in the years to come," the AAR statement said.