The EPA issued a decision on March 31, 2023, granting two requests for waivers of preemption regarding four California Air Resources Board (CARB) regulations related to California’s heavy-duty vehicle and engine emissions standards.
California has significant air quality standard challenges. In order to reduce emissions, the state must seek waivers from the EPA for new vehicle emissions standards. The Clean Air Act (CAA) gives states broad discretion to meet air quality challenges, according to the EPA.
“Section 209 of the Clean Air Act authorizes EPA to adopt vehicle emission standards and preempts state regulation in the field, except for California, which may adopt its own regulations that are stricter than federal standards upon successful application to EPA for a preemption waiver,” says a Lexology article by Jones Day.
“Under the [CAA], California has longstanding authority to address pollution from cars and trucks. [This] announcement allows the state to take additional steps in reducing their transportation emissions through these new regulatory actions,” said EPA Administrator Michael S. Regan in an Agency news release.
In this instance, CARB requested two waivers for regulations relating to heavy-duty vehicles and engines. After reviewing the technical information provided by CARB, reviewing comments submitted by the public, and applying the limited authority for review under Section 209 of the CAA, the EPA decided to grant the waiver and authorization requests.
These waivers of preemption address the following California programs:
- The 2018 Heavy-Duty 2018 Warranty Amendments, which extend the emissions warranty periods for 2022 and subsequent model year on-road heavy-duty diesel engines and for 2022 and subsequent model year diesel vehicles with a gross vehicle weight rating exceeding 14,000 pounds powered by such engines.
- The Advanced Clean Trucks (ACT) Regulation, which requires manufacturers to produce and sell increasing quantities of medium- and heavy-duty zero-emission vehicles (ZEVs) and near zero-emission vehicles (NZEVs) in California. This waiver request also includes two additional regulations:
- The Zero Emission Airport Shuttle Bus (ZEAS) Regulation, which establishes steadily increasing zero-emission airport shuttle fleet composition requirements for airport shuttle fleet owners who service the 13 largest California airports.
- The Zero Emission Powertrain (ZEP) Certification Regulation, which establishes certification requirements and optional emissions standards for 2021 and subsequent model year medium- and heavy-duty ZEVs and the zero-emission powertrains installed in such vehicles.
“EPA has also conducted a public comment process regarding CARB’s Heavy-Duty Omnibus Low NOx Regulation which establishes criteria pollutant exhaust emission standards for nitrogen oxide (NOx) and particulate matter (PM) as well as other emission-related requirements for new 2024 and subsequent model year on-road medium- and heavy-duty engines and vehicles,” adds the EPA news release. “CARB has asked EPA for additional time before the Agency acts on the waiver request for this regulation. EPA expects to act upon this waiver request as appropriate.”
A virtual public hearing was held on June 28, 2022, covering all three proposed actions. The written comment period for the proposed actions closed August 2, 2022.
For more information, see:
- The EPA website on the California waiver program
- The EPA website on California Waiver Requests for Heavy-Duty Vehicle Emission Regulations