California has decided to abandon key regulations aimed at phasing out diesel trucks and introducing cleaner locomotives. The state had pushed for these rules to tackle severe air pollution and fight climate change. However, with the incoming Trump administration expected to oppose these efforts, state officials believe it is unlikely they will be able to implement them.
The move follows a recent approval from the Biden administration for California’s plan to phase out new gas-powered cars by 2035. However, the U.S. Environmental Protection Agency (EPA) has yet to approve four other diesel vehicle regulations adopted by the state.
President-elect Donald Trump has previously threatened to revoke or challenge California’s clean-air standards, including those aimed at reducing emissions from vehicles. With this in mind, the Newsom administration has decided to withdraw its waiver requests from the EPA, signaling a shift in strategy as California prepares for the new political era.
California Withdraws Waiver Requests
California’s Air Resources Board Chair, Liane Randolph, confirmed that the state is withdrawing pending waiver requests that the EPA had not yet acted upon. She expressed disappointment that the EPA did not act in time, but emphasized that the decision was necessary due to uncertainty about the incoming administration’s stance on the state’s air quality programs.
Environmental advocates have expressed concern, stating that the withdrawal puts public health at risk and undermines vital programs aimed at reducing pollution.
“California must transition to zero-emissions trucks and trains to meet basic air quality standards,” said Paul Cort, director of Earthjustice’s Right To Zero campaign. “Diesel is a major health hazard, and the state’s diesel problem is significant enough to affect millions.”
Impact of the Advanced Clean Fleet Rule
One of the most ambitious measures California had introduced was the Advanced Clean Fleet rule, which would have phased out diesel trucks. This rule, approved in 2022 after extensive discussions, required large trucking companies to shift to electric or hydrogen-powered trucks by 2042. It aimed to eliminate diesel’s dominance in goods transportation, with far-reaching environmental and economic impacts.
However, trucking industry representatives have opposed the rule, arguing that electric and hydrogen-powered trucks are not feasible for long-haul transportation. They warned that the rule would hurt California’s economy.
“The Advanced Clean Fleets Rule is unachievable,” said Eric Sauer, CEO of the California Trucking Association. He emphasized the need for practical and cost-effective measures to reduce emissions while preserving the state’s supply chain.
Other Regulations on Diesel Emissions Also Withdrawn
California also withdrew three additional rules aimed at reducing emissions from diesel-powered locomotives, commercial harbor craft, and refrigeration unit engines. These regulations were particularly crucial for communities near ports, freeways, and rail yards that have long suffered from toxic diesel fumes.
Under one proposed rule, only locomotives under 23 years old could operate in California after 2030, unless they were zero-emission. Railroads, however, argued that zero-emission locomotive technology is not yet viable, and the timeline was unrealistic.
California’s Unique Emissions Authority Under Threat
California has had the unique ability to set stricter emission standards since the 1960s, thanks to a waiver granted by the EPA. This authority was upheld during most administrations, including when the Trump administration attempted to strip it away. While the Biden administration reversed that effort in 2022, California air quality officials had been waiting years for the EPA’s approval of the remaining regulations.
But with time running out and the Trump administration poised to take office, California decided to withdraw its waiver requests. Air Resources Board Chair Liane Randolph explained that maintaining control over the waivers was crucial, given the uncertainty of what the incoming administration would do.
Litigation Likely Under New Administration
Randolph also predicted that litigation would increase under the Trump administration. Business groups have already challenged the state’s clean car mandate, and the new administration is expected to intensify opposition to California’s environmental rules.
While California may have to scale back future vehicle regulations during the Trump era, officials are considering working with industries on voluntary agreements to continue progress on air quality.
The Road Ahead for California’s Clean Air Efforts
Despite these setbacks, California remains committed to improving air quality and addressing climate change. The Air Resources Board plans to continue exploring options to advance its clean air goals.
The truck fleet rule, if fully implemented, would have affected 1.8 million medium and heavy-duty trucks in California, including those used by major companies like FedEx, UPS, and Amazon. Despite the suspension of some provisions, electric and hydrogen trucks are already being adopted by companies like Pepsi and Amazon, signaling ongoing progress toward zero-emission fleets.
In 2023, one in six medium and heavy-duty trucks sold in California was a zero-emission vehicle, indicating the growing trend toward cleaner transportation options even without mandated deadlines.
California’s Air Resources Board continues to assess its options for moving forward, with a focus on protecting public health and tackling the state’s air pollution and climate challenges.
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