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EPA & CA Air Resources Board Team Up to Reduce Locomotive Emissions - Here's What You Need to Know

Railroad locomotives, which typically burn massive amounts of diesel fuel, are a significant mobile source of air pollution, especially in areas near railroad yards and industrial facilities in which trains operate. Now, the California Air Resources Board (CARB) and the U.S. Environmental Protection Agency (EPA) are now teaming up in an effort to curb these harmful emissions - but the partnership has sparked controversy. Namely, two questions have arisen:

  1. Is CARB allowed to set emission standards for locomotives?

  2. Can EPA let it?

GASP’s senior attorney John Baillie explains… Some Needed Background Info Section 213(a)(5) of the Clean Air Act gives the EPA the authority to set emission standards for “new locomotives and new engines used in locomotives.” The agency first promulgated regulations setting such emission standards in 1997. Stricter emission standards for newer locomotives were set by supplemental regulations that became effective in 2008. “Under EPA’s regulations, railroad locomotives are assigned to one of five tiers, labeled Tiers 0, 1, 2, 3, and 4, based on when they were originally manufactured, and must continue to meet the emission standards applicable to their Tier when they are remanufactured,” Baillie explained. “The lower the number of the Tier, the older, and more polluting, the locomotive.”

As one would expect, the emission standards for newer locomotives (specifically Tiers 3 and 4, which were set by that 2008 reg we mentioned earlier) are significantly stricter than those for older locomotives (specifically, Tiers 0, 1, and 2).

Tier 3 and 4 locomotives are more expensive to manufacture and operate than lower-Tier locomotives, and thus, railroads have tended to keep lower Tier, more-polluting locomotives in service for longer than regulators anticipated in 1997 or 2008.

“This has apparently caused some frustration in California and other areas where locomotives’ emissions contribute substantially to air pollution problems, including particularly chronic ground-level ozone pollution,” Baillie said.

Who Has the Power (to Regulate)?

Until recently, it was assumed that state regulators were without power to regulate locomotives’ emissions, and that EPA’s emission standards for locomotives would preempt any state’s attempt to do so.

However, on Nov. 8 EPA published a final rule that purportedly would authorize it to waive federal emission standards for “non-new” locomotives - those operating with engines that have exceeded 133% of their useful lives - at CARB’s request.

“CARB is attempting to impose its own standards on locomotives that operate in California, which, as a practical matter, could include all locomotives in interstate rail service as well as the locomotives of railroads based in California,” Baillie said.

CARB’s emission standards for locomotives would require railroads to pay fees into spending accounts based on the amount of their locomotive emissions; the railroads would also be required to use the money in those accounts to upgrade existing Tier 0, 1, and 2 locomotives to Tier 4 (and beginning in 2030, zero emission) locomotives.

CARB’s standards would also prohibit locomotives from idling for longer than 30 minutes.

The Railroad Industry Response? A Legal Challenge

The railroad industry has already filed an action challenging the legality of CARB’s standards in a federal district court in California, arguing that the standards are - despite EPA’s new waiver rule - preempted by federal laws governing railroads and locomotives, including:

What Happens Now?

It is not at all clear that CARB has the authority to enforce its emission standards for locomotives or that EPA has the authority to allow it. “Several court decisions have held that state regulations regarding locomotive emissions are indeed preempted by these and other federal laws,” Baillie said. “Nevertheless, if the CARB emission standards survive in the courts, they will eventually work a massive reduction in the pollution produced by locomotives.” We will continue to follow this issue and report on new developments as they occur.

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