Not later than 180 days after the date on which proposed regulations are issued pursuant to subsection (a), the Administrator shall solicit the views of the agency heads referred to in section 1419(b) of this title and of interested persons, consider the comments received during the public hearing required in subsection (a) and any written comments on the proposed regulations received by the Administrator, and issue, in accordance with section 553 of title 5, such regulations as are required by or are necessary and appropriate to implement subchapters I and II and this subchapter.