EPA is revising the format of 40 CFR part 52 for materials submitted by Memphis-Shelby County that are incorporated by reference (IBR) into the State Implementation Plan (SIP). The regulations affected by this format change have all been previously submitted by the local agency and approved by EPA. This format revision will affect the "Identification of Plan" sections of 40 CFR part 52, as well as the format of the SIP materials that will be available for public inspection at the Office of the Federal Register (OFR), the Air and Radiation Docket and Information Center, and the Regional Office. The sections of 40 CFR part 52 pertaining to provisions promulgated by EPA or local-submitted materials not subject to IBR review remain unchanged.