Hidden in the New EPA Rules: A Turning Point for Zero Emissions Trains

Buried at the bottom of the Environmental Protection Agency’s draft rules on greenhouse gas limits for cars and trucks was a proposal related to another highly polluting form of transit: trains.

The EPA said Wednesday it was considering giving states more authority to regulate locomotives, specifically citing concern that its current policy could impede California’s “exploration of regulations” for trains and train engines. The Golden State has been lobbying the EPA to tighten its standards for locomotives, or to allow it to do so, for years. However, a 1998 rule limits states' ability to regulate emissions for a range of nonroad vehicles, including trains.

I’m not going to pretend this could be a huge deal for climate change. Trains are responsible for just 2% of transportation emissions in the U.S. This is, however, a huge deal for public health and environmental justice. Exposure to diesel exhaust causes lung cancer. Trains also emit nitrogen oxides and particulate matter, which irritate the lungs, exacerbate respiratory diseases including asthma, and contribute to premature deaths. Rail yards are often located near densely populated areas and disproportionately neighbor low-income communities that suffer from a combination of economic, health, and environmental burdens.

But while public health is the most urgent reason to cut pollution from trains, the most promising solutions to address that pollution — batteries and hydrogen fuel cells — will also pretty much eliminate the climate impacts of trains, as a treat.

California petitioned the EPA to tighten its standards for trains back in 2017. “We cannot deliver on our collective responsibility to improve conditions on the ground for overburdened communities without new action by U.S. EPA to require a transition to zero and near-zero emission locomotives,” wrote Mary Nichols, then-chair of the California Air Resources Board, or CARB, the state agency that regulates emissions.

CARB’s concern isn’t just public health, but federal compliance. The state is not on track to meet federal air quality standards. California’s rail yards are already a major source of pollution, and rail operators are planning expansions. The state expects freight rail to increase 50% in the next seven years.

“Locomotives are so dirty that state regulators identified reducing their pollution as the biggest single strategy in their plan to reduce smog to federal health standards by 2037 — responsible for more than 30% of the emissions cuts needed, more than any other sector, including all cars and trucks on the road,” the Los Angeles Times’ editorial board wrote in a recent piece on the need to clean up the rail industry.

“California is a leader on climate,” said Chris Chavez, deputy policy director for the Coalition for Clean Air, a statewide organization working on air quality issues. “The problem is that we still have the dirtiest air in the nation.”

Part of the challenge is that trains are incredibly durable. They are typically “remanufactured,” or repaired and restored, every seven to 10 years, but can otherwise stick around for decades. EPA tightened its emissions standards for locomotives in 2008, but “remanufactured” trains aren’t required to upgrade to the highest standards. Chavez said that in the South Coast Air Quality Management District, a region that encompasses Orange County and much of Los Angeles, some 30% to 50% of the trains still only meet the dirtiest, lowest-level EPA standards. “Those are the most polluting engines that are available and they’re in the dirtiest air basin in the country.”

Under the Trump administration, California’s petition went unanswered. But late last year, Biden’s EPA finally responded. Though it didn’t commit to tightening standards for trains at the federal level, the agency said it had assembled a “rail study team” to evaluate technologies to reduce train emissions, as well as policy options to get the industry to turn over its fleet to trains with newer, cleaner technologies more quickly. It also hinted that it was planning to clarify its policy on state-promulgated regulations.

California hasn’t been idly standing by. State regulators determined that although they had no authority to regulate the manufacture of locomotives, they could issue rules for railroad operators and the types of equipment they use. Next month, CARB is expected to vote on a set of new rules designed to force the industry to begin retiring its oldest trains and replacing them with newer, cleaner models, and by 2035, with zero- or near zero-emission trains that are powered by batteries, overhead electric lines, or hydrogen fuel cells. While the regulations would pertain to trains that are “in-use” in California, it would have implications for the whole of North America, since the rail system is interconnected, and trains frequently travel far beyond their owners’ tracks.

The Inflation Reduction Act could help. The legislation included $3 billion for grants and rebates to reduce air pollution from ports and $60 million for the Diesel Emissions Reduction Act program, which funds pollution reduction projects related to transportation in low-income and disadvantaged communities.

CARB’s rules are sure to face litigation from the rail industry, which claims that the “entire proposed regulation is preempted by federal laws and regulations.” The Association of American Railroads says the industry is already working toward zero-emission rail, with major railroads like BNSF and Union Pacific piloting battery-electric and hydrogen fuel cell trains, but that these solutions won't be commercially available “for the foreseeable future.” But the EPA could soon strengthen California’s case.