The director shall prescribe the method for making application for certification, and may issue such rules and regulations as are necessary to administer this section and sections 620.1350 and 620.1355. No rule or portion of a rule promulgated under the authority of this section and sections 620.1350 and 620.1355 shall become effective unless it has been promulgated pursuant to the provisions of chapter 536. All rulemaking authority delegated prior to June 27, 1997, is of no force and effect and repealed; however, nothing in this section and sections 620.1350 and 620.1355 shall be interpreted to repeal or affect the validity of any rule filed or adopted prior to June 27, 1997, if such rule complied with the provisions of chapter 536. The provisions of this section and sections 620.1350 and 620.1355 and chapter 536 are nonseverable and if any of the powers vested with the general assembly pursuant to chapter 536, including the ability to review, to delay the effective date, or to disapprove and annul a rule or portion of a rule, are subsequently held unconstitutional, then the purported grant of rulemaking authority and any rule so proposed and contained in the order of rulemaking shall be invalid and void.