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National Pollutant Discharge Elimination System (NPDES)

Pretreatment Roles and Responsibilities-Control Authorities

Where a POTW has an approved local pretreatment program, the POTW is the control authorityHelpcontrol authorityThe POTW, in the case of a POTW with an approved pretreatment program, or the Approval Authority, in the case of a POTW without an approved pretreatment program. [paraphrased from 40 CFR 403.3(f)]. Where a POTW has not received approval, the control authority is the approved state or, in unapproved states, the EPA.

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Control Authorities' Responsibilities

The control authorities:

  • develop legal authority for their jurisdiction, local limits, standard operating procedures, and an enforcement response plan to establish and maintain an approved pretreatment program.
  • regulate IUs by:
    • issuing control mechanisms,
    • conducting monitoring and inspections,
    • receiving and reviewing reports and notifications,
    • reviewing requests for net/gross variances,
    • evaluating compliance with program requirements, and
    • taking enforcement as appropriate.
  • submit regular reports to approval authorities to describe the implementation of their pretreatment program.

The control authority is responsible for administering and enforcing pretreatment standards and requirements. The control authority’s primary goals are:

After the approval authorityHelpapproval authorityThe director in an NPDES Authorized State with an approved state pretreatment program, or the appropriate EPA regional administrator in a non-NPDES Authorized State or NPDES state without an approved state pretreatment program. [40 CFR 403.3(c)] - the EPA or approved state – approves a POTW’s pretreatment program, the POTW becomes the control authority. If the POTW is not required to develop an approved local pretreatment program and become the control authority, the approved pretreatment state or the EPA region (where the state is not approved), assumes responsibility as the control authority over industrial users discharging to the POTW.

Developing an Approvable Pretreatment Program

The POTW submits the pretreatment program package to the approval authority for review and approval according to the requirements at 40 CFR Part 403.9 (PDF)(2 pp, 184 K). In addition to containing all the required elements, the package must also describe how the POTW will maintain the key components of its pretreatment program.

POTW pretreatment requirements at 40 CFR Part 403.8(f)(1) through (6) (PDF)(7 pp, 232 K) outline the key components of an approved POTW pretreatment program:

Once the approval authority (EPA or approved state pretreatment program) approves the POTW program, the POTW becomes the control authority to implement the local program.

Periodically, the control authority must modify its approved pretreatment program. Procedures for the modification of POTW pretreatment programs are outlined at 40 CFR 403.18 (PDF)(2 pp, 184 K). Common reasons for modifications include regulation changes (federal, state, or local) and adoption of new local limits. For example, a POTW may not have previously accepted hauled waste, and later modifies its program to incorporate legal authority, standard procedures, and pretreatment standards that apply to hauled waste.

Implementing an Approved Pretreatment Program

The control authority must have adequate legal authority to implement its pretreatment program, as stated in the regulations at 40 CFR Part 403.8(f)(1) (PDF)(7 pp, 232 K). A control authority regulating IUs outside of its legal jurisdiction (e.g., IUs outside of a POTW’s political boundaries) must have the necessary legal authority to ensure that the program procedures can be implemented there, too. The legal authority must enable the POTW to:

  • deny or condition discharges to the POTW,
  • require compliance with pretreatment standards and requirements,
  • control IU discharges through permits, orders, or similar means,
  • require IU compliance schedules when necessary to meet applicable pretreatment standards and/or requirements and the submission of reports to demonstrate compliance,
  • inspect and monitor IUs;
  • obtain remedies for IU noncompliance, and
  • comply with confidentiality requirements.

Using legal authority, the control authority must develop and implement the required procedures outlined at 40 CFR Part 403.8(f)(20 (PDF)( pp, 232 K) to:

  • Identify and locate all IUs subject to the pretreatment programs.
  • Identify the character and volume of pollutants discharged to the POTW. The POTW will maintain an index or inventory of IUs and update the list, submitting changes to the list annually to their Approval Authorities per 40 CFR Part 403.12(i) (PDF)(10 pp, 216 K).
  • Notify IUs of applicable pretreatment standards and requirements. Frequently, POTWs provide this notification by issuing a permit or control mechanism that identifies applicable limitations and reporting requirements.
  • Receive and analyze reports and notices from the IUs.
  • Sample and analyze IU discharges and, specifically, inspect and sample SIUs annually.
  • Evaluate IUs and require measures for controlling non-routine, episodic discharges, including spills, that might cause interference or pass through or violate the POTW regulations.
  • Investigate IU noncompliance, developing and using an Enforcement Response Plan (“ERP”).
  • Provide sufficient funding, resources, personnel to carry out the requirements.
  • Develop and enforce local limits, or demonstrate that they are not necessary.
  • Submit an annual report with a summary of program activities, including a summary of IU compliance, enforcement actions, and changes to the POTW pretreatment program to the approval authority.

Learn more about requirements for controlling hauled waste.

Additional Information

To assist the control authority in developing and implementing its pretreatment programs, EPA provides the following guidance:

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