Advisories June 25, 2024

Environmental, Land Use & Natural Resources Advisory: California’s Advanced Clean Fleets Regulation Under Attack

Executive Summary
Minute Read

California’s ambitious zero-emission, heavy-duty truck regulations face new legal challenges. Our Environment, Land Use & Natural Resources Group outlines the status of California’s Advanced Clean Fleet (ACF) Regulation, pending litigation, and important deadlines.

  • Status of California waiver request and enforcement notice for advanced clean fleets
  • Lawsuits filed by coalitions of states challenging the ACF Regulation
  • Deadlines for compliance and effect of enforcement notice

Through the Advanced Clean Fleets (ACF) Regulation, the California Air Resources Board (CARB) requires truck fleets operating in California to transition to zero-emissions vehicles over time, with interim compliance milestones and reporting requirements. The regulations affect fleets of 50 trucks or more if they travel to California, even if based out of state. With other states promising to follow California’s lead, truck fleet operators within and outside California may be affected as these developments unfold.

Status of California Waiver Request and Enforcement Notice for Advanced Clean Fleets

CARB adopted the ACF Regulation in April 2023; the regulation became effective on October 1, 2023. On November 15, 2023, CARB submitted a waiver request to the U.S. Environmental Protection Agency (EPA), contending it does not require EPA’s grant of a waiver of federal preemption that ordinarily prohibits states from establishing emissions standards for new motor vehicles or, alternatively, that if a waiver were required one would be granted. This waiver request is pending.

CARB published an enforcement notice on December 28, 2023 stemming from discussions between CARB and the California Trucking Association in CTA v. CARB, No. 2:23-cv-02333, in the Eastern District of California stating that CARB will exercise its enforcement discretion and refrain from taking enforcement action against the ACF’s drayage fleet and high-priority fleet categories and their reporting requirements and registration prohibitions until the EPA grants a waiver that applies to those regulatory provisions or determines a waiver is not necessary. However, CARB encouraged fleets to voluntarily report and comply while the waiver request is pending and reserved its rights to enforce the ACF in full for any period for which a waiver is granted or for which a waiver is determined to be unnecessary, including the right to remove noncompliant vehicles added to fleets while the waiver request is pending.

Nebraska Leads State Coalition in Lawsuit Against California

On May 13, 2024, Nebraska filed a complaint for declaratory judgment and injunctive relief in the Eastern District of California against CARB and the state of California. The petition alleges that the ACF runs afoul of the U.S. Constitution, Clean Air Act (CAA), and Federal Aviation Administration Authorization Act of 1994 (FAAAA).

Specifically, the petition alleges that by requiring the replacement of internal-combustion engine (ICE) trucks with zero-emissions trucks, the ACF harms the plaintiff states by reducing their tax revenue levied on fuel sales. Additionally, the complaint alleges that due to California’s centrality to interstate and international trade, the ACF will cause more battery-electric vehicles to drive in and through the plaintiff states and that because those vehicles are generally heavier than their ICE counterparts, roads will degrade faster. Plaintiff states also allege they will incur costs to provide sufficient electricity to meet the increased demand for electricity.

The complaint also alleges that Section 209 of the Clean Air Act, which provides an exception to preemption for California emissions standards, does not cover the ACF because the regulation bans entire categories of engine technology and is aimed at reducing greenhouse gas emissions rather than eliminating pollutants that create unique local conditions in California. Additionally, the complaint argues that EPA cannot issue a preemption waiver for the additional reason that any California waiver must be “consistent with” the EPA’s power to regulate emissions and the EPA has the power only to set “standards” for emissions—not to wholesale ban vehicles with internal-combustion engines from the roads. The complaint further argues that the ACF violates equal sovereignty because it allows solely California to enact regulatory measures unavailable to every other state.

The complaint goes on to allege that the ACF violates the dormant Commerce Clause of the U.S. Constitution and is preempted by the FAAAA.

The plaintiff states request that the court declare the ACF is preempted by federal statutes, violates the U.S. Constitution, and is unenforceable and that it issue an injunction preventing the implementation or enforcement of the ACF. A scheduling order has not yet been entered.

Western States Petroleum Association Suit Challenging the ACF

On July 21, 2023 the Western States Petroleum Association (WSPA) filed a complaint challenging the ACF in the California Superior Court for Fresno County. The complaint alleges that the ACF violates both California and federal laws, including the California Health and Safety Code, California Environmental Quality Act (CEQA), California Administrative Procedure Act, the principle of separation of powers, vested rights of business owners in California, and U.S. Constitution. The complaint asks the court to issue a writ of mandate directing CARB to vacate and set aside its approval of the ACF and to declare the rules “void, invalid, and of no legal effect.”

This case is still pending. On May 15, 2024, the court entered an order and stipulation continuing the hearing on WSPA’s motion for preliminary injunction to August 7, 2024.

Western States Trucking Association v. CARB

On July 21, 2023, the Western States Trucking Association (WSTA) filed a petition for writ of mandate and complaint for declaratory and injunctive relief challenging the ACF in California superior court. The petition and complaint seek to invalidate the ACF on the grounds that CARB failed to evaluate the ACF for potential environmental impacts under CEQA, failed to adequately address the ACF’s economic impacts and consider alternatives under the California Administrative Procedure Act, and failed to engage in external peer review of the “scientific portions” of the ACF as required by the California Health and Safety Code.

On May 15, 2024, an order was entered continuing the hearing on WSTA’s motion for preliminary injunction and associated briefing deadlines. The hearing on the WSTA’s motion for preliminary injunction is now set for August 7, 2024.

ACF Deadlines and Effect of the CARB Enforcement Notice

The drayage truck requirements to report combustion-powered vehicles for drayage truck operation was December 31, 2023. Although the CARB enforcement notice indicates that CARB will not take enforcement action against drayage fleet reporting requirements or registration prohibitions until a waiver is granted or determined to be unnecessary, combustion-powered vehicles added to the reporting system that were not previously reported by this date may be restricted from performing drayage services if the waiver is granted or determined to be unnecessary.

The high-priority and federal fleet reporting deadline was January 1, 2024. The CARB enforcement notice states that reporting is optional until a waiver is granted or determined to be unnecessary. However, combustion-powered vehicles added into service in California after December 31, 2023 may be restricted from operating if a waiver is granted or determined unnecessary. Importantly, this means that if a waiver is granted (or determined unnecessary), fleets may need to remove vehicles from their fleet that were not eligible to be added after January 1, 2024, or the fleet must elect to comply with the Zero-Emission Vehicle (ZEV) Milestone Option to obtain flexibility.

State and local fleet reporting, ICE phase-out, and ZEV phase-in requirements began on January 1, 2024. The CARB enforcement notice asserts that CARB is not required to request a waiver for state and local fleets. Therefore, CARB began fully enforcing all requirements, including reporting and ZEV purchasing requirements, on January 1, 2024. 


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