; and (bb) the date on which the Administrator validates an effective quality control and testing procedure for the perfluoroalkyl or polyfluoroalkyl substance or class of perfluoroalkyl or polyfluoroalkyl substance, if such a procedure did not exist on the date on which the toxicity value described in item (aa) was finalized. (II) Waiver The Administrator may waive the requirements of subclause (I) with respect to a perfluoroalkyl or polyfluoroalkyl substance or class of perfluoroalkyl and polyfluoroalkyl substances if the Administrator determines that there is a substantial likelihood that the perfluoroalkyl or polyfluoroalkyl substance or class of perfluoroalkyl or polyfluoroalkyl substances will not occur in drinking water. . 6722. Monitoring and detection (a) Monitoring program for unregulated contaminants (1) In general The Administrator shall include each substance described in paragraph (2) in the fifth publication of the list of unregulated contaminants to be monitored under section 1445(a)(2)(B)(i) of the Safe Drinking Water Act ( 42 U.S.C. 300j–4(a)(2)(B)(i) ). (2) Substances described The substances referred to in paragraph (1) are perfluoroalkyl and polyfluoroalkyl substances and classes of perfluoroalkyl and polyfluoroalkyl substances— (A) for which a method to measure the level in drinking water has been validated by the Administrator