40 CFR § 65.12
Delegation of authority
June 9, 2020
(a) In delegating implementation and enforcement authority to a State under sections 111(c) and 112(l) of the Act, the authorities contained in paragraph (b) of this section shall be retained by the Administrator and not transferred to a State.
(b) Authorities that will not be delegated to States: §§65.8, 65.46, 65.102, 65.156(b)(l)(ii), and 65.158(a)(2)(ii).