Control of Air Pollution: Emission Standards for New Nonroad Compression-Ignition Engines at or Above 37 Kilowatts; Preemption of State Regulation for Nonroad Engine and Vehicle Standards; Amendments to Rules

This direct final rulemaking, consistent with an order and opinion from the U.S. Court of Appeals for the District of Columbia Circuit, amends EPA's regulations setting emission standards for large (at or above 37 kilowatts) nonroad compression ignition engines, and EPA's regulations establishing procedures for EPA authorization of California nonroad emission standards. Specifically, EPA is withdrawing portions of an interpretive rule which set forth the Agency's position on the Clean Air Act (Act) regarding the status of certain internal combustion engines manufactured before the effective date of the final rulemaking promulgating EPA's definition of nonroad engine. Additionally, consistent with the D.C. Circuit opinion, EPA also is amending the remaining text of this interpretive rule, as well as EPA's regulations issued under section 209(e) of the Act regarding the Agency's California nonroad standards authorization process, to clarify that California must seek authorization from EPA prior to enforcing standards and other requirements relating to emissions from any nonroad vehicles or engines, and not just new nonroad vehicles and engines, which was the original language used in these regulations.