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National Pollutant Discharge Elimination System (NPDES)

Pretreatment Roles and Responsibilities

These three entities have the role and responsibility to develop and implement the national pretreatment program:

  • Approval authorities
    • Director in an NPDES authorized state with an approved state pretreatment program, and the appropriate EPA regional administrator in a non-NPDES authorized state or NPDES state without an approved state pretreatment program.
  • Control authorities
    • The publicly owned treatment works (POTW), for a POTW with an approved pretreatment program, or the approval authority, for a POTW without an approved pretreatment program.
  • Industrial users (IUs)
    • A nondomestic source of indirect discharge into a POTW.