On May 1, 2015, the U.S. Court of Appeals for the D.C. Circuit vacated the provisions in the RICE NESHAP and NSPS allowing emergency engines to operate for up to 100 hours per year for emergency demand response when an Energy Emergency Alert Level 2 has been called, and in situations where the voltage or frequency deviates by 5 percent or greater below standard. Subsequent to the court decision, EPA asked the court for a voluntary remand of provisions in the same regulations allowing emergency engines to operate for up to 50 hours per year to mitigate local transmission and/or distribution limitations in a local area or region. This action will address the provision for operation for up to 50 hours per year for local reliability, for which EPA has requested a voluntary remand.