((a)) ** Regulations; delegation of powers and duties; regional officers and employees**
((1)) The Administrator is authorized to prescribe such regulations as are necessary to carry out his functions under this chapter. The Administrator may delegate to any officer or employee of the Environmental Protection Agency such of his powers and duties under this chapter, except the making of regulations subject to , as he may deem necessary or expedient.
((2)) Not later than one year after , the Administrator shall promulgate regulations establishing general applicable procedures and policies for regional officers and employees (including the Regional Administrator) to follow in carrying out a delegation under paragraph (1), if any. Such regulations shall be designed—
((A)) to assure fairness and uniformity in the criteria, procedures, and policies applied by the various regions in implementing and enforcing the chapter;
((B)) to assure at least an adequate quality audit of each State’s performance and adherence to the requirements of this chapter in implementing and enforcing the chapter, particularly in the review of new sources and in enforcement of the chapter; and
((C)) to provide a mechanism for identifying and standardizing inconsistent or varying criteria, procedures, and policies being employed by such officers and employees in implementing and enforcing the chapter.
((b)) ** Detail of Environmental Protection Agency personnel to air pollution control agencies** Upon the request of an air pollution control agency, personnel of the Environmental Protection Agency may be detailed to such agency for the purpose of carrying out the provisions of this chapter.
((c)) ** Payments under grants; installments; advances or reimbursements** Payments under grants made under this chapter may be made in installments, and in advance or by way of reimbursement, as may be determined by the Administrator.
((d)) ** Tribal authority**
((1)) Subject to the provisions of paragraph (2), the Administrator—
((A)) is authorized to treat Indian tribes as States under this chapter, except for purposes of the requirement that makes available for application by each State no less than one-half of 1 percent of annual appropriations under ; and
((B)) may provide any such Indian tribe grant and contract assistance to carry out functions provided by this chapter.
((2)) The Administrator shall promulgate regulations within 18 months after , specifying those provisions of this chapter for which it is appropriate to treat Indian tribes as States. Such treatment shall be authorized only if—
((A)) the Indian tribe has a governing body carrying out substantial governmental duties and powers;
((B)) the functions to be exercised by the Indian tribe pertain to the management and protection of air resources within the exterior boundaries of the reservation or other areas within the tribe’s jurisdiction; and
((C)) the Indian tribe is reasonably expected to be capable, in the judgment of the Administrator, of carrying out the functions to be exercised in a manner consistent with the terms and purposes of this chapter and all applicable regulations.
((3)) The Administrator may promulgate regulations which establish the elements of tribal implementation plans and procedures for approval or disapproval of tribal implementation plans and portions thereof.
((4)) In any case in which the Administrator determines that the treatment of Indian tribes as identical to States is inappropriate or administratively infeasible, the Administrator may provide, by regulation, other means by which the Administrator will directly administer such provisions so as to achieve the appropriate purpose.
((5)) Until such time as the Administrator promulgates regulations pursuant to this subsection, the Administrator may continue to provide financial assistance to eligible Indian tribes under .