The ACC program—which applies to light-duty vehicles, light-duty trucks, and medium-duty passenger vehicles—comprises four separate regulations to address ambient air quality and climate change. The regulations together are designed to encourage coordinated development, introduction, and sales of advanced technologies so as to support investment in infrastructure and reduce technology costs. The updated ZEV, GHG, and LEVIII criteria emission standards regulations are covered under the ACC waiver. The fourth regulation establishes requirements for electric and hydrogen infrastructure improvements and is not subject to federal preemption.

The LEVIII amendments establish more stringent criteria and GHG emission standards starting with the 2015 and 2017 MYs, respectively. The new ZEV standards are designed to commercialize battery-electric, plug-in hybrid, and fuel cell technologies, reaching about 15% of new vehicle sales in California in the 2025 time frame.

In reaching its waiver decision, EPA determined that the CARB ZEV amendments as they affect 2017 and earlier MYs are within the scope of prior EPA waivers. EPA also determined that the waiver includes the new “deemed to comply” regulation.

Background. The Clean Air Act pre-empts states from adopting emission standards for new motor vehicles, but establishes specific provisions through which California may obtain a waiver of federal preemption.

ARB submitted a request to EPA for a waiver of preemption for its ACC regulations on 27 June 2012. On 31 August 2012, EPA announced an opportunity for public hearing and comment on the California request. A hearing took place on 19 September 2012 in Washington DC and the comment period closed on 19 October 2012.

EPA received comment from organizations representing auto manufacturers and dealers, emission control manufacturers, states, businesses, consumer and environmental organizations, and the general public. The large majority of comments urged EPA to grant the waiver. EPA received two opposing comments; one recommended outright denial and the other recommended denial or deferral of certain components of the ACC program.

However, EPA determined that these opponents of the waiver had not demonstrated the burden of proof necessary for EPA to deny a waiver based on the waiver criteria found in the Clean Air Act.

EPA provides a detailed discussion of its decision and rationale in the Federal Register Notice.