The no action alternative assumes, for the purpose of NEPA (National Environmental Policy Act) analysis, that NHTSA would not issue a rule regarding CAFE standards. NEPA requires agencies to consider a no action alternative in their NEPA analyses and to compare the effects of not taking action with the effects of the reasonable action alternatives in order to demonstrate the different environmental effects of the action alternatives.

The Preferred Alternative will reflect annual stringency increases for both passenger cars and light trucks that fall at levels between the upper and lower bounds identified above. NHTSA has not yet identified its Preferred Alternative.

Similar to past EIS practice, NHTSA plans to analyze environmental impacts related to fuel and energy use, emissions including GHGs and their effects on temperature and climate change, air quality, natural resources, and the human environment. NHTSA also will consider the cumulative impacts of the proposed standards for MY 2017–2025 automobiles together with any past, present, and reasonably foreseeable future actions.

To account for uncertainty in estimating the potential environmental impacts related to climate change, NHTSA plans to evaluate a range of potential global temperature changes that may result from changes in fuel and energy consumption and GHG emissions attributable to new CAFE standards.

NHTSA intends to rely upon the Intergovernmental Panel on Climate Change (IPCC) 2007 Fourth Assessment Report and subsequent updates; Reports of the US Climate Change Science Program (CCSP) and the current US Global Change Research Program (US GCRP); National Academies and National Research Council assessments of climate impacts; and the EPA Endangerment Finding) as sources.

The newly published notice initiates the scoping process by inviting comments from Federal, State, and local agencies, Indian tribes, and the public to help identify the environmental issues and reasonable alternatives to be examined in the EIS.

NHTSA says it is especially interested in comments concerning the evaluation of climate change impacts. In particular, NHTSA requests:

Background. The action is part of a joint rulemaking with EPA, in which EPA plans to issue greenhouse gas standards for the same model year vehicles. This is the second phase of a National Program under which the two agencies establish harmonized requirements to improve the fuel economy and reduce the GHG emissions of new passenger cars and light trucks sold in the US. (Earlier post, earlier post.)

NHTSA’s statutory authority allows the agency to take final action prescribing CAFE standards in increments of no more than five model years. In order to address this statutory limitation, NHTSA is considering proposing standards for the MY 2017–2025 timeframe, with the express condition that the standards for MYs 2022–2025 would be subject to a mid-term technology assessment and review.

In other words, NHTSA would adopt standards for MYs 2017–2025, but standards for MYs 2022–2025 would not become effective at the established level unless and until NHTSA affirmed in a later rulemaking that they were, based on information available at the time of the later rulemaking, the maximum feasible standards for those model years.

NHTSA’s upcoming NPRM will propose separate attribute-based (vehicle footprint, as in the phase I CAFE standards) standards for MY 2017– 2025 passenger cars and for MY 2017–2025 light trucks. Each individual vehicle model would have a specific fuel economy target based on the fuel economy capability of those motor vehicles having the same footprint as that vehicle model.

A manufacturer’s CAFE standard would be based on the target levels set for its particular mix of vehicles in that model year. Compliance would be determined by comparing a manufacturer’s harmonically averaged fleet fuel economy levels in a model year with a required fuel economy level calculated using the manufacturer’s actual production levels and the targets for each vehicle it produces.