40 CFR Part 1068, Subpart C - Exemptions and Exclusions

EPA and NHTSA, on behalf of the Department of Transportation, are establishing rules for a comprehensive Phase 2 Heavy-Duty (HD) National Program that will reduce greenhouse gas (GHG) emissions and fuel consumption from new on-road medium- and heavy-duty vehicles and engines. NHTSA's fuel consumption standards and EPA's carbon dioxide (CO 2 ) emission standards are tailored to each of four regulatory categories of heavy-duty vehicles: Combination tractors; trailers used in combination with those tractors; heavy-duty pickup trucks and vans; and vocational vehicles. The rule also includes separate standards for the engines that power combination tractors and vocational vehicles. Certain requirements for control of GHG emissions are exclusive to the EPA program. These include EPA's hydrofluorocarbon standards to control leakage from air conditioning systems in vocational vehicles and EPA's nitrous oxide (N 2 O) and methane (CH 4 ) standards for heavy-duty engines. Additionally, NHTSA is addressing misalignment between the Phase 1 EPA GHG standards and the NHTSA fuel efficiency standards to virtually eliminate the differences. This action also includes certain EPA-specific provisions relating to control of emissions of pollutants other than GHGs. EPA is finalizing non-GHG emission standards relating to the use of diesel auxiliary power units installed in new tractors. In addition, EPA is clarifying the classification of natural gas engines and other gaseous-fueled heavy-duty engines. EPA is also finalizing technical amendments to EPA rules that apply to emissions of non-GHG pollutants from light-duty motor vehicles, marine diesel engines, and other nonroad engines and equipment. Finally, EPA is requiring that engines from donor vehicles installed in new glider vehicles meet the emission standards applicable in the year of assembly of the new glider vehicle, including all applicable standards for criteria pollutants, with limited exceptions for small businesses and for other special circumstances.

In this action, the Administrator finds that elevated concentrations of greenhouse gases in the atmosphere endanger the public health and welfare of current and future generations within the meaning of section 231(a)(2)(A) of the Clean Air Act (CAA, or Act). She makes this finding specifically with respect to the same six well-mixed greenhouse gases—carbon dioxide (CO 2 ), methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride—that together were defined as the air pollution in the 2009 Endangerment Finding under section 202(a) of the CAA and that together constitute the primary cause of the climate change problem. The Administrator also finds that emissions of those six well-mixed greenhouse gases from certain classes of engines used in certain aircraft are contributing to the air pollution—the aggregate group of the same six greenhouse gases—that endangers public health and welfare under CAA section 231(a)(2)(A).

This Notice provides an opportunity to comment on new information being made available by the EPA and by NHTSA, on behalf of DOT, related to the proposed Phase 2 Heavy-Duty National Program proposed July 13, 2015, to reduce greenhouse gas emissions and fuel consumption for new on-road heavy-duty vehicles and engines. The new information, including memoranda and data, have been placed in the public dockets. Data relating to the potential stringency of the proposed standards includes: Powertrain data; additional aerodynamic test data; supplemental test data relating to drive cycles (and frequency thereof) for vocational vehicles; and cycle average mapping data. The agencies are soliciting additional comment on certain revised test reports, and a revised version of the Greenhouse Gas Emission Model (GEM) used both in developing certain of the proposed standards and in demonstrating compliance with those standards. Additionally, EPA is soliciting further comment on memoranda relating to standard applicability and implementation. These memoranda address potential requirements for selective enforcement audits and confirmatory testing related to greenhouse gas emissions, and applicability of emission standards and certification responsibilities for trailers, glider vehicles, and glider kits. Finally, EPA is soliciting additional comments on issues discussed in a late comment related to light-duty motor vehicles used for racing.