Director means the Regional Administrator, the State director or the Tribal director as the context requires, or an authorized representative. When there is no approved State or Tribal program, and there is an EPA administered program, Director means the Regional Administrator. When there is an approved State or Tribal program, Director normally means the State or Tribal director. In some circumstances, however, EPA retains the authority to take certain actions even when there is an approved State or Tribal program. (For example, when EPA has issued an NPDES permit prior to the approval of a State program, EPA may retain jurisdiction over that permit after program approval; see 123.1) In such cases, the term Director means the Regional Administrator and not the State or Tribal director.
40 CFR § 124.2
In addition to the definitions given in 122.2 and 123.2 (NPDES), 501.2 (sludge management), 144.3 and 145.2 (UIC), 233.3 (404), and 270.2 and 271.2 (RCRA), the definitions below apply to this part, except for PSD permits which are governed by the definitions in 124.41. Terms not defined in this section have the meaning given by the appropriate Act.