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  2. National Pollutant Discharge Elimination System (NPDES)

NPDES WET Methodology Documents

Documents on NPDES WET methodology.

  • Clarifications Regarding Toxicity Reduction and Identification Evaluations in the NPDES Program (pdf) (82.47 KB)
  • Clarifications Regarding Toxicity Reduction and Identification Evaluations in the NPDES Program Memo (pdf) (221.97 KB)
  • Clarifications Regarding Whole Effluent Toxicity Test Methods Recently Published at 40 CFR Part 136 and Guidance on Implementation of Whole Effluent Toxicity in Permits (pdf) (736.87 KB)
  • Errata for the Effluent and Receiving Water Toxicity Testing Manuals (pdf) (58.47 KB)
  • Generalized Methodology for Conducting Industrial Toxicity Reduction Evaluations (TREs) (pdf) (1.42 MB)
  • Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures Second Edition (pdf) (2.01 MB)
  • Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Samples Exhibiting Acute and Chronic Toxicity (pdf) (973.01 KB)
  • Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (pdf) (392.38 KB)
  • Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I (pdf) (5.43 MB)
  • Marine Toxicity Identification Evaluation (TIE) Phase I Guidance Document (pdf) (3.06 MB)
  • Manual for the Evaluation of Laboratories Performing Aquatic Toxicity Tests (pdf) (3.88 MB)

National Pollutant Discharge Elimination System (NPDES)

  • About NPDES
    • Permit Basics
    • State Program Information
    • Permit Limits
    • Program Management and Oversight
    • NPDES Regulations
    • Other Federal Laws that Apply to the NPDES Permit Program
  • All NPDES Program Areas
    • Animal Feeding Operations
    • Aquaculture
    • Forest Roads
    • Industrial Wastewater
    • Municipal Wastewater
      • Combined Sewer Overflows (CSOs)
      • Sanitary Sewer Overflows (SSOs)
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      • Standards and Requirements
      • Roles and Responsibilities
      • Events, Training and Webinars, and Publications
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      • Construction Activities
      • Industrial Activities
      • Municipal Sources
      • Transportation Sources
      • Oil and Gas Permitting
      • Stormwater Planning
      • EPA's Residual Designation Authority
      • Rules and Notices
    • Water Quality Trading
  • NPDES Technical Resources
    • Resources for Permit Writers
    • NPDES Permit Writers' Manual
    • NPDES Training
    • Tools
    • Electronic Notice of Intent (eNOI)
    • NPDES Applications and Forms
Contact Us About NPDES
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on June 17, 2024
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