The announcement signals EPA’s intent to publish a proposed rule in 2020.

By Arthur F. Foerster

On November 13, the United States Environmental Protection Agency (EPA) announced its “Cleaner Trucks Initiative” (CTI) to further decrease oxides of nitrogen (NOx) emissions from on-highway trucks and engines. EPA intends to publish a proposed rule in early 2020, which will both reduce emissions and also “cut unnecessary red tape while simplifying certification of compliance requirements.” According to EPA’s announcement, deregulatory efforts will center around onboard diagnostic requirements (OBD), reassuring real-world compliance, recertification, and certain types of testing. The announcement stated, “New programs borne out of the CTI offer opportunities to streamline regulations through smarter program design and reduce the overall regulatory burden while protecting human health and the environment.”

EPA’s Acting Administrator, Andrew Wheeler, launched the initiative and was joined by labor and industry representatives, EPA and White House officials, and certain state partners. Wheeler did not provide a specific proposal, only touching on a broad framework for the eventual rule. However, he did say that “reducing NOx emissions from heavy-duty vehicles is a clean air priority for this administration.” According to Wheeler, “the Cleaner Trucks Initiative will help modernize heavy-duty truck engines, improving their efficiency and providing cleaner air for all Americans.”

The announcement signals that the Trump EPA appears to be carrying on with the Obama EPA’s pursuit of NOx reductions for on-highway, heavy-duty diesel vehicles and engines, despite the fact that the agency has reconsidered some Obama EPA decisions with respect to emissions reductions for various vehicle groups. At the tail-end of the Obama administration, EPA formally responded to petitions for rulemaking — championed by various interests in California and elsewhere — calling for EPA to promulgate new “ultra-low” NOx emission standards for on-highway, heavy-duty diesel engines. More specifically, the petitioners sought a 90% reduction from the current 0.2 g/bhp-hr NOx standard down to 0.02 g/bhp-hr. The Obama EPA agreed with the sentiment, if not with the exact result or aggressive timing set forth in the petitions. EPA expressed the need for a new, lower standard and, without pre-deciding what that standard would be, stated its intent to initiate rulemaking by collecting and analyzing technical data, with the goal of having a new standard in effect by the 2024 model year.

Whether the Trump EPA’s latest action will lead to a 50-state solution in the heavy-duty space remains to be seen. Since 1967, Section 209 of the Clean Air Act (codified at 42 U.S.C. § 7543) has granted California the ability to set more stringent emission standards for motor vehicles and engines than federal standards that would otherwise preempt state regulation. To do so, California must seek a “waiver” under the Clean Air Act from EPA. If a waiver is granted, certain other states may then adopt California’s standards pursuant to Section 177 of the Act (codified at 42 U.S.C. § 7507). California has clashed with the Trump EPA regarding modifications to the Obama EPA’s greenhouse gas (GHG) standards for cars and other light-duty vehicles. And, it was interests in California who submitted the original petitions for rulemaking to EPA for further NOx reductions for on-highway, heavy-duty engines and vehicles. California continues to pursue its own low-NOx standard, questioning whether a preferred 50-state approach is within reach.