; and (iv) a determination, in accordance with the requirements of the Federal Water Pollution Control Act, whether or not to establish effluent limitations and pretreatment standards for the introduction or discharge of each substance described in clause (iii) that the Administrator determines under such clause not to add to such list and for which the Administrator has not developed such limitations or standards. (2) Regulation Based on the results of each review conducted under paragraph (1) and in accordance with the requirements of the Federal Water Pollution Control Act, the Administrator shall— (A) in accordance with the plan published under paragraph (1), as soon as practicable— (i) for each measurable perfluoroalkyl and polyfluoroalkyl substance that the Administrator determines under paragraph (1)(B)(iii) to add to the list of toxic pollutants described in section 307(a) of such Act, initiate the process for adding the substance to such list; and (ii) for each measurable perfluoroalkyl and polyfluoroalkyl substance that the Administrator determines under paragraph (1)(B)(iv) to establish effluent limitations and pretreatment standards, establish such effluent limitations and pretreatment standards (which limitations and standards may be established by substance or by class or category of substances)