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EPA Moving Full Steam Ahead with Process to OK CA Emissions Standards for Railroad Locomotives


A few months back we blogged about the California Air Resources Board’s (also known as CARB) adoption of a regulation that would, over time, require the phase out of older, more polluting railroad locomotives to be replaced first with lower-emission locomotives and eventually with zero emission locomotives. 


CARB’s regulation could help reduce ozone and particulate matter pollution and improve air quality substantially in areas that are close to busy railroad tracks and freight yards, and generally reduce the railroad industry’s greenhouse gas emissions.  


The regulation would on its face be limited to locomotives operating in California but would have implications across the United States and beyond, because most locomotives do not stay in one state and may move anywhere within the continental United States, Canada, or Mexico.  Any locomotive that traveled into California would be subject to the regulation even if the locomotive mainly operated elsewhere.    


CARB’s regulation already faces a legal challenge from the railroad industry in a federal district court based in Sacramento. As we noted before, the industry claims that the regulation is inconsistent with the Clean Air Act, pre-empted by other federal statutes, and barred by the Interstate Commerce Clause of the United States Constitution.


While that challenge winds its way through the courts, however, the U.S. Environmental Protection Agency (EPA) published a notice last week that it will hold a virtual public hearing and accept written comments on the discrete issue of whether CARB’s regulation meets the requirements for EPA authorization under Section 209 of the Clean Air Act – EPA is not empowered to determine whether the regulations may be inconsistent with or preempted by other federal statutes or the Constitution itself.  


Under Section 209, the states are generally barred from setting emission standards for nonroad engines or vehicles, but EPA may authorize such a standard established by California (only, not any other state) if three conditions are met:


  1. California’s determination that it needs the standard is not “arbitrary and capricious;”

  2. California needs the standard “to meet compelling and extraordinary conditions;” and

  3. the California standard “and accompanying enforcement procedures” are consistent with Section 209

Accordingly, EPA has requested that comments be limited to these issues:


(a) whether CARB’s determination that its standards, in the aggregate, are at least as protective of public health and welfare as applicable federal standards is arbitrary and capricious; 


(b) whether California needs such standards to meet compelling and extraordinary conditions; and 


(c) whether California’s standards and accompanying enforcement procedures are consistent with section 209 of the Act.



You can submit written documents any time before March 24 at https://www.regulations.gov; identify your comments by Docket ID No. EPA-HQ-OAR-2023-0574.  


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