EPA Emissions Proposal for Heavy-Duty Vehicles May Carry Significant Costs

The Environmental Protection Agency (EPA) wants to curb emissions from on-highway, heavy-duty vehicles, a move that could carry a hefty compliance pricetag.

Agency officials have proposed a rule that applies to nitrogen-mix emissions from heavy-duty trucks and buses, according to a description of the rule on the Office of Management and Budget’s (OMB) website. The intended rule — which was submitted to the OMB for review in December and has yet to clear the agency — is classified as “economically significant,” meaning it is projected to cost at least $100 million per year to implement.

The main target of the rule is oxides of nitrogen (NOx), a class of pollutants that includes nitric oxide and nitrogen dioxide, the latter of which is a component of smog.

“This rulemaking will address significant public health and environmental justice concerns caused by pollution from internal combustion engines while supporting early introduction of zero emission technologies,” the proposal states.

Plans to curb nitrogen-mix emissions have been in the works since November 2018, when the EPA first announced the Cleaner Trucks Initiative (CTI), which targeted emissions. This is the first of these planned rules, which the agency hopes to finalize this year and apply to 2027 model trucks.

The agency is weighing a variety of projects and studies to inform all of these proposed rules, including onboard NOx sensors and diesel engine aftertreatment technology.