EPA proposes weakening heavy-duty truck pollution rules

The Trump administration is proposing changes to what it calls "unnecessary and unworkable" Biden-era environmental rules designed to cut pollution from heavy-duty vehicles, including buses and large trucks.

The proposal — part of a series of deregulatory actions by the Trump administration that have rolled back emissions standards for new vehicles — includes changes that are welcomed by trucking organizations and denounced by environmental groups.

Specifically, the proposal from the Environmental Protection Agency would scale back and postpone two provisions designed to make sure emissions-reducing technology keeps working while a vehicle is in use; one related to warranties, and another related to the useful life of emissions technology.

Additionally, the current set of rules requires truck engines to automatically operate at reduced power if their emissions reduction systems aren't working, which truckers and other heavy-duty vehicle operators have called disruptive. The EPA proposes getting rid of that requirement altogether and replacing it with an alert to drivers.

According to the EPA's analysis, the changes would save the trucking industry between $4,130 and $6,152 per diesel engine affected. Compared to the current emissions rules, the change would increase ozone-forming nitrogen oxide pollution from heavy duty trucks by 4.2% in 2030 and by 11.6% by 2055.

The EPA did not model the resulting effect on air quality or human health, but noted that the modifications would likely reduce the benefits of prior rules changes in 2023.

The proposal is now open for a period of public comment.

"If finalized, these changes will help manufacturers keep improving their vehicles without being forced to rush products to market before they're ready," EPA administrator Lee Zeldin said in a statement, adding that the rules changes "will ease real burdens for operators."

Kelly Loeffler, who heads the U.S. Small Business Administration, wrote that the rules change would alleviate "burdensome diesel regulations on behalf of farmers, truckers, and small business owners who were crushed by unworkable environmental activist demands that became costly mandates."

The American Trucking Associations had called for changes to the rules, writing in February that the Biden-era policies would require "a premature rollout of commercial motor vehicles with unproven engine technologies onto our highways." The group specifically asked the agency to allow truck manufacturers to pay penalties instead of comply with the rules, as long as they were working on developing compliant engines, an option the EPA included in the proposal.

Environmental groups criticized the proposed changes, citing concerns about the health hazards of emissions. "Clean truck standards save lives," Katherine García, director of the Sierra Club's Clean Transportation for All campaign, wrote in a statement emailed to NPR. "Weakening them would mean more toxic pollution in the air and more families paying the price with their health.

The Environmental Defense Fund noted that while heavy trucks make up only 5% of vehicles on U.S. roads, they are the largest source of "pollutants that cause asthma attacks, bronchitis, heart attacks, strokes and preventable deaths," and argued that truck manufacturers are already capable of meeting the Biden-era rules.

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