California Withdraws Clean Air Act Waiver Requests for Vehicle Emissions Standards

On Monday, January 13, 2025, California withdrew requests for Clean Air Act waivers from the EPA needed to support four recently adopted vehicle emissions regulations:  1) the Advanced Clean Fleets Regulations; 2) the In-Use Locomotive Regulations; 3) part of the Commercial Harbor Craft and Ocean-Going Vessels At-Berth Regulations; and 4) part of the Transport Refrigeration Unit Engine Standards Regulations. According to a statement from Liane Randolph, chair of the California Air Resources Board (CARB), California withdrew the waiver requests due to the uncertainty caused by the impending change in federal administration. The regulations covered by the withdrawn waiver requests include emissions standards that impact broad swaths of industrial, commercial, and governmental activity in California.

In order for California to promulgate vehicle emission standards without violating the Clean Air Act, it must receive a waiver from the EPA for any state law that regulates vehicles covered by the Act. The Clean Air Act generally prohibits any state from adopting or enforcing “any standard relating to the control of emissions from new motor vehicles or new motor vehicle engines” that are otherwise subject to the Act. However, the Clean Air Act allows any state “which has adopted standards (other than crankcase emission standards) for the control of emissions from new motor vehicles or new motor vehicle engines prior to March 30, 1966” to receive a waiver from this prohibition. California is the only state to have adopted such standards by the cutoff date, so it is the only state allowed to seek such a waiver. The Act also allows other states to adopt California’s emission standards for which waivers have been granted. To date, EPA has granted more than 100 of California’s waiver requests.

In recent weeks, EPA has been evaluating waiver requests for multiple vehicle emission regulations adopted by California over the past few years. In December, EPA granted waivers for California’s Advanced Clean Cars II regulation, which requires all new passenger cars sold in California to be zero emission by 2035, and the “Omnibus” regulation, which is aimed at reducing NOx and other emissions from heavy duty vehicles.

Notably, the recent withdrawal of the four pending waiver requests does not mean the regulated community can ignore the legal requirements set forth in these regulations, at least until such time as CARB repeals the regulations or they are invalidated by a court. While certain aspects of these regulations are likely unenforceable absent a Clean Air Act waiver, other portions may not be subject to the Clean Air Act and the waiver requirement. For example, CARB has asserted that it is not required to request a waiver for a part of the Advanced Clean Fleet regulation that applies only to state and local government fleets. CARB may therefore carve out and fully enforce that part while repealing, instituting a policy of non-enforcement, or taking other action regarding the remainder.

Due to the wide-ranging impact of the affected regulations, we anticipate that CARB may issue statements in the near future addressing how it plans to proceed with the regulations. Allen Matkins will be monitoring CARB’s activity and reporting on any significant developments regarding the impacted regulations.