; and (ii) incorporate an integral performance indication device as specified in section 6.1 of NSF/ANSI standard 53–2017; or (B) shall be certified as compliant with any standards adopted by NSF International, ANSI, or the Agency that are more stringent than the standards under subparagraph (A). (b) Approval Not later than 6 months after a community water system submits a plan under this section, the Administrator shall approve the plan or notify the community water system in writing of revisions the Administrator determines necessary to approve the plan. (c) Implementation Not later than 10 years after a plan under this section of a community water system is approved by the Administrator, the community water system shall submit to the Administrator a certification that all the lead service lines of the community water system have been replaced except for any lead service line not owned by the community water system and with respect to which the owner has declined replacement by the community water system. (d) Extension (1) Application A community water system may submit an application to the Administrator for an extension of the 10-year deadline described in subsection (c). (2) Approval The Administrator shall approve an application for an extension under paragraph (1) only if— (A) the community water system submitting the application has held a public hearing and solicited public comment prior to submitting the application