1. The director may adopt, amend, promulgate or repeal, after due notice and hearing, rules and regulations to implement sections 260.500 to 260.552 pursuant to this section and chapter 536. No rule or portion of a rule promulgated under the authority of sections 260.500 to 260.552 shall become effective unless it has been promulgated pursuant to the provisions of section 536.024.

2. Except as provided in sections 260.565 to 260.573, the director shall not promulgate rules that are stricter than, apply prior to, or apply mandatory obligations outside of the requirements of Title 40, U.S. Code of Federal Regulations, as promulgated pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act, as amended.

3. The director shall file with the Missouri secretary of state any amendments necessary to ensure that rules are not inconsistent with the provisions of this section. Any rule contained in the Missouri code of state regulations that is inconsistent with the provisions of this section shall be null and void to the extent that it is inconsistent, and the least stringent rule shall control. Any such rule that applies mandatory obligations outside of the requirements of Title 40, U.S. Code of Federal Regulations, Part 300, as promulgated pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act, as amended, shall be null and void.