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Thompson Hine LLP, a full-service business law firm with approximately 400 lawyers in 8 offices, was ranked number 1 in the category “Most innovative North American law firms: New working models” by The Financial Times and was 1 of 7 firms shortlisted for The American Lawyer’s inaugural Legal Services Innovation Award. The firm has been recognized by the National Law Journal as a Legal Technology Trailblazer and featured by Bloomberg for its innovative service delivery models, which drive accuracy and predictability. The firm’s commitment to innovation is embodied in Thompson Hine SmartPaTHTM – a smarter way to work – predictable, efficient and aligned with client goals. For more information, please visit ThompsonHine.com and ThompsonHine.com/SmartPaTH.

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CARB has withdrawn several preemption waiver requests to EPA.

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The Trump administration could revoke or deny additional preemption waiver requests.

The future of CARB’s zero emissions vehicle, engine and equipment strategy is uncertain.

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On January 13, 2025, the California Air Resources Board (CARB) made the unprecedented decision to <a href="https://www.regulations.gov/document/EPA-HQ-OAR-2023-0589-0470">withdraw its pending request</a> to the EPA for a federal Clean Air Act (CAA) waiver to implement a key aspect of CARB’s <a href="https://ww2.arb.ca.gov/our-work/programs/advanced-clean-fleets">Advanced Clean Fleets (ACF) regulation</a>. The waiver would have permitted CARB to implement the drayage and “high priority fleets” provisions of the ACF. CARB introduced the ACF regulation in April 2023, but the California Trucking Association’s subsequent lawsuit, which alleged that an EPA waiver was required, prompted CARB to submit the waiver request to the EPA in November 2023. In addition to the California Trucking Association’s challenge, three other lawsuits challenging the ACF were filed between 2023 and 2024 by the Western States Trucking Association, the American Free Enterprise Chamber of Commerce, and the National Truck Equipment Association and Specialty Equipment Market Association. These suits raised several legal claims, including allegations that the ACF was unconstitutional and was preempted by the Clean Air Act, and that CARB had failed to adequately assess the environmental and economic impacts of the regulation.

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EPA Inaction and CARB Strategic Withdrawal

With the Biden administration ending and the EPA yet to act on the ACF waiver request, CARB appears to have acted strategically to avoid a likely rejection under the incoming Trump administration. During the public comment period, the EPA received over 41,000 comments on the ACF waiver request, but no decision was issued.

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In response to the withdrawal of the ACF waiver request, the EPA <a href="https://www.epa.gov/system/files/documents/2025-01/hd-acf-carb-waiver-withdraw-resp-2025-1-14.pdf">responded</a> on January 14, 2025, briefly stating it placed CARB’s letter in the EPA regulatory docket, is “taking no further action on the [ACF waiver request],” and “considers this matter closed.”

The ACF was a cornerstone of CARB’s ambitious zero-emissions strategy to transition California’s medium- and heavy-duty trucking industry to zero emissions by 2045. It complemented the Advanced Clean Trucks (ACT) regulation, which requires vehicle manufacturers to gradually increase production and sale of zero-emission heavy duty-trucks from 2024 to 2035. While the ACT targets manufactures, the ACF focused on fleet owners, mandating the purchase of zero-emission vehicles to accelerate industry-wide adoption.

The ACF, as promulgated, applied to California fleets in three categories: (1) those performing drayage operations, (2) public fleets owned by state, local, or federal government agencies, and (3) “high-priority fleets.” The ACF defines high-priority fleets as entities with at least $50 million in gross annual revenue that own, operate, or control at least one vehicle with a gross vehicle weight rating (GVWR) over 8,500 pounds, or entities that own, operate, or control a total of 50 or more vehicles exceeding this weight threshold. CARB’s decision to withdraw the &nbsp;waiver request only impacts the drayage and high-priority fleet provisions of the ACF. The public fleet provisions &nbsp;remain unaffected, as they did not require a federal waiver for implementation.

CARB’s decision to withdraw the ACF waiver request was likely influenced by its expectation that the ACF and other pending waivers would likely face rejection under the new administration. During President Trump’s first term, the EPA revoked a previously granted waiver for CARB’s Advanced Clean Cars I regulation, and similar actions could be taken against pending or issued waivers, including those for the current Advanced Clean Cars II regulation.

Following the withdrawal, CARB Chair Liane Randolph issued a statement affirming CARB’s commitment to improving California’s air quality while expressing disappointment over the EPA’s inaction on the waiver request. Although the future of the ACF remains uncertain, the recent developments and expected priorities of the next Trump administration suggest that CARB is unlikely to revive the drayage and high-priority fleet provisions of the ACF within the next four years.&nbsp;

For now, CARB’s withdrawal of the ACF waiver request alleviates regulated entities from the extensive obligations imposed by the ACF. These include planning for and purchasing an increasing number of zero-emission vehicles as well as meeting various reporting and recordkeeping requirements.

In addition to the ACF waiver, CARB also withdrew its waiver requests for a portion of the Zero-Emission Truck Transport Refrigeration Unit (TRU) requirements and for the In-Use Locomotive Regulation. Both waivers were key components of CARB’s broader efforts to advance zero-emission vehicle and engine initiatives.

Thompson Hine will continue to monitor these developments and possible future changes to issued and pending CARB waiver requests to the EPA.

<em>This advisory bulletin may be reproduced, in whole or in part, with the prior permission of Thompson Hine LLP and acknowledgment of its source and copyright. This publication is intended to inform clients about legal matters of current interest. It is not intended as legal advice. Readers should not act upon the information contained in it without professional counsel.</em> <em>This document may be considered attorney advertising in some jurisdictions.</em>

https://admin.thompsonhine.com/wp-content/uploads/2025/01/CARB-Withdraws-Key-Waiver-Request-for-Zero-Emission-Regulation.pdf

CARB Withdraws Key Waiver Request for Zero-Emission Regulation

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