In a significant policy shift, the California Air Resources Board (CARB) has withdrawn its request for a federal waiver to enforce the Advanced Clean Fleets (ACF) rule, effectively halting its mandate for fleets to phase in zero-emission vehicles (ZEVs). The decision comes mere days before President-elect Donald Trump’s inauguration for a second term on January 20.
The move signals a strategic recalibration by CARB, anticipating resistance from the incoming administration, which has pledged to roll back emissions regulations. On Monday, CARB Executive Officer Steven Cliff submitted a formal letter to the Environmental Protection Agency’s (EPA) acting administrator, officially withdrawing the request.
Industry Response: Relief and Criticism of ACF
The trucking industry and its advocates have welcomed CARB’s decision with open arms. Chris Spear, president and CEO of the American Trucking Associations (ATA), praised the move, calling the ACF rule a “job-killing regulation” that posed risks to both industry viability and consumers. Spear expressed optimism about the Trump administration’s ability to dismantle remaining CARB waivers and establish a more balanced approach to environmental regulation.
“America’s truckers deserve an EPA leader who will work productively with industry to set federal emissions standards that are achievable and do not risk disrupting our supply chains,” Spear stated in a letter supporting President-elect Trump’s EPA nominee, Lee Zeldin. Spear also criticized the EPA under the current administration for creating a fragmented regulatory landscape that prioritized California’s mandates over cohesive federal standards.
David Heller, senior vice president of safety and government affairs at the Truckload Carriers Association, echoed these sentiments, emphasizing the impact of the industry’s advocacy. “The withdrawal of this waiver request represents a significant milestone in our efforts to curb unattainable regulations,” Heller said, describing the decision as a victory for the trucking sector.
A Strategic Withdrawal Amid Political Tensions
CARB’s withdrawal appears to be a calculated decision, acknowledging the incoming administration’s strong opposition to emissions mandates. President-elect Trump has repeatedly criticized regulations targeting the transition to zero-emission vehicles, promising to end such mandates “on day one.” During his first term, Trump revoked a previous CARB waiver and signaled his intention to curtail California’s unique authority under the Clean Air Act to set stricter emissions standards than federal guidelines.
California lawmakers have already begun preparing for anticipated clashes with the Trump administration. In December, the state convened a special legislative session to strategize responses to potential federal rollbacks of environmental policies. Meanwhile, Trump’s EPA nominee, Lee Zeldin, is expected to spearhead deregulatory efforts, including the denial of pending CARB waivers.
Zeldin has received widespread support from industry groups like the ATA, which have argued that CARB’s ACF regulation imposed “unworkable mandates on unrealistic timelines.” Under the ACF rule, fleets were required to phase in ZEVs, with a long-term mandate for manufacturers to produce only zero-emission trucks by 2036. The regulation has been widely criticized for its economic and logistical challenges, particularly given its ambitious timeline.
The Broader Context of EPA Waivers and ACF
Under the Clean Air Act, California holds the unique ability to set emissions standards stricter than federal guidelines, provided it secures a waiver from the EPA. Other states may then choose to adopt these standards. CARB’s ACF rule represented the final piece of a trio of heavy-duty emissions regulations. While the Advanced Clean Trucks and Omnibus rules received EPA waivers, ACF had yet to gain approval, leaving its enforcement in limbo.
The ACF regulation aimed to accelerate the adoption of ZEVs in the transportation industry, a critical step in California’s broader climate goals. However, the rule has faced significant opposition from industry stakeholders, who argue that the mandates are economically burdensome and technologically impractical within the proposed timeline.
What Lies Ahead
CARB’s decision to withdraw its ACF waiver request highlights the increasing polarization surrounding environmental policy and the trucking industry’s transition to zero-emission technologies. As the Trump administration prepares to assume office, the regulatory landscape for emissions standards is likely to shift dramatically. With federal priorities leaning toward deregulation, California and other states committed to aggressive climate action may face heightened challenges in advancing their environmental agendas.
For now, the trucking industry is celebrating a reprieve, while California’s environmental leaders prepare for a new chapter in their ongoing battle over emissions regulation. The ultimate outcome will shape the future of clean transportation in the United States and the balance between environmental progress and economic feasibility.