California State Nonroad Engine Pollution Control Standards; Small Off-Road Engines Regulations; Tier 4 Off-Road Compression-Ignition Regulations; Exhaust Emission Certification Test Fuel for Off-Road Spark-Ignition Engines, Equipment, and Vehicles Regulations; Notice of Decision

The Environmental Protection Agency (EPA) is confirming that the California Air Resources Board's (CARB's) 2011 amendments to its Small Off-Road Engines (SORE) regulations (2011 SORE amendments), Tier 4 Off-Road Compression-Ignition (CI) regulations (2011 Tier 4 amendments), and Exhaust Emission Certification Test Fuel for Off-Road Spark-Ignition (SI) Engines, Equipment, and Vehicles regulations (2011 Certification Test Fuel amendments) are within the scope of previous EPA authorizations. The 2011 SORE amendments modify California's existing SORE test procedures by aligning California procedures to be consistent with recent amendments by EPA to the federal certification and exhaust emission testing requirements. The 2011 Tier 4 amendments enhance the harmonization of CARB's exhaust emission requirements for new off-road CI engines with the corresponding federal emissions requirements for nonroad CI engines. The 2011 Certification Test Fuel amendments modify the certification test fuel requirements for off-road spark ignition, gasoline-fueled engines to allow the use of 10-percent ethanol-blend gasoline (E10) as a certification fuel. This decision is issued under the authority of the Clean Air Act (``CAA'' or ``Act'').