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Modifying Your Approved Pretreatment Program

Definition of substantial and non-substantial modifications to approved TPDES pretreatment programs for POTWs.

Modifications to Incorporate the Pretreatment Streamlining Rule

Modifications to an approved pretreatment program may be initiated by the publicly owned treatment works (POTW) (40 CFR §403.3(q)) or required by the Texas Commission on Environmental Quality (TCEQ) through the Texas Pollutant Discharge Elimination System (TPDES) permit. A modification is required when there is a significant change in the operation of the approved pretreatment program or to reflect changing conditions at the POTW.

There are two types of pretreatment modifications defined in 40 CFR §403.18 :

Before being implemented, all modifications must be:

Substantial Modifications

A substantial modification includes the following:

  • relaxing POTW legal authorities

  • relaxing local limits

  • changes to the type of control mechanism issued to regulated facilities

  • a decrease in the frequency of self-monitoring or reporting required of regulated facilities

  • a decrease in the frequency of inspections or sampling of regulated facilities by the POTW

  • changes to the POTW's confidentiality procedures

  • other modifications designated as substantial modifications by the TCEQ

In most cases, substantial modifications require that all elements of the pretreatment program be submitted to the TCEQ for review and approval. Substantial modifications are approved and incorporated in the POTW's TPDES permit, and are effective on the date of issuance of the permit.

Other (Nonsubstantial) Modifications

All other modifications must be submitted to the TCEQ 45 days before being implemented. Indicate the portion or portions of the Pretreatment Program that will be affected by the modification.

Modifications to Incorporate the Pretreatment Streamlining Rule

The U.S. Environmental Protection Agency (EPA) revised the 40 CFR Part 403 on October 14, 2005, called the “Pretreatment Streamlining Rule.” Listed below are the modifications that incorporate the Pretreatment Streamlining Rule required changes.

  • Slug control requirements must be included in SIU control mechanisms [§403.8 (f)(1)(iii)(B)(6)].

  • SIUs must be evaluated for the need for a plan or other action to control slug discharges within a year from the final rule’s effective date or from becoming an SIU [§403.8 (f)(2)(vi)].

  • SIUs are required to notify the POTW immediately of any changes at its facility affecting the potential for a slug discharge [§403.8 (f)(2)(vi)]

  • Significant noncompliance (SNC) definition is expanded to include additional types of pretreatment standards and requirements [§403.8 (f)(2)(viii)(A)-(C)]

  • SIU reports must include best management practices (BMPs) compliance information [§403.12 (b), (e), (h)].

  • SIU control mechanisms must contain any BMPs required by a pretreatment standard, local limits, state, or local law [§403.8 (f)(1)(iii)(B)(3)].

  • Documentation of compliance with BMP requirements must be maintained as part of the SIU’s and POTW’s record-keeping requirements [§403.12 (o)].

  • Control Authorities which perform sampling for SIUs must perform any required repeat sampling and analysis within 30 days of becoming aware of a violation [§403.12 (g)(2)].

  • Require periodic compliance reports to comply with sampling requirements, require Control Authority to specify the number of grab samples necessary in periodic and noncategorical SIU reports, and require noncategorical SIUs to report all monitoring results [§403.12 (g)(3), (4), (6)].

  • Noncategorical SIUs are required to provide representative samples in their periodic monitoring reports [§403.12 (g)(3)].

  • Require notifications of changed discharge to go to the Control Authority and the POTW, where the POTW is not the Control Authority [§403.12 (j)].

  • How and when the POTW can designate a “duly authorized employee” to sign POTW reports [§403.12 (m)].

In addition, any POTW may propose any of the “optional” modifications from the Pretreatment Streamlining Rule. Once approved by the TCEQ and incorporated into the TPDES permit or accepted by the TCEQ as nonsubstantial modifications, these "optional" modifications become required elements of the approved pretreatment program.

Please click on the link for the U.S. Environmental Protection Agency's website regarding the Pretreatment Streamlining Rule Fact Sheets 1 , 2 , 3 , 4 , 5 , 6 , 7 and 8 .

Pretreatment Streamlining Rule Modifications Process

Please note that the Pretreatment Streamlining Rule draft modification submittal package will be submitted as a complete replacement of your approved pretreatment program.

  1. Complete and submit the draft modification package along with the complete Pretreatment Streamlining Rule checklists listed below.

    • Legal Authority Checklist

    • Enforcement Response Plan and Guide Checklist

    • Standard Operating Procedures Checklist

    • Forms (Inspection Form, Permit Template, Permit Application) Checklist

    • Required Elements Checklist

    • CA Slug Control Checklist

    • CA Sampling Protocols Checklist, if applicable

    Contact the Pretreatment Team to obtain the Word versions of the checklists listed above that need to be completed and submitted with a new pretreatment program, Streamlining Rule modification, or a substantial modification package.

  2. Additional checklists for the optional modifications from the Pretreatment Streamlining Rule include:

    • Optional Elements
    • Sampling For Pollutants Not Present
    • CIU Oversight
    • General Permits
    • Equivalent Mass for Concentration Limits
  3. The TCEQ will determine if the modifications submitted to incorporate the Pretreatment Streamlining Rule are nonsubstantial, according to 40 CFR §403.18 (b)(1), and if any revisions are required.

    • All of the changes related to the Pretreatment Streamlining Rule may be treated as non substantial, if the changes to a POTW's legal authority to incorporate the changes directly reflect the federal requirements. 40 CFR §403.18 (b)(1).

    • The EPA further excludes from the definition of 'substantial modification' those changes in POTW legal authority that result in less prescriptive programs, but which directly reflect a revision to the federal pretreatment regulations. 40 CFR §403.18 (b)(1).

    • Such modifications would have already undergone public notice and comment when promulgated by EPA. As long as the POTW's local ordinance is revised to directly reflect the federal requirements, further public notice would be unnecessary. Federal Register Volume 62 July 17, 1997 Pages 38406, 38409 .

    • Incorporate the final Pretreatment Streamlining Rule modifications into your approved pretreatment program and submit the package according to TCEQ instructions provided for your individual pretreatment program.

Contact us if you have questions.