Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

    • Environmental Topics
    • Air
    • Bed Bugs
    • Cancer
    • Chemicals, Toxics, and Pesticide
    • Emergency Response
    • Environmental Information by Location
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Radon
    • Research
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History

Breadcrumb

  1. Home
  2. National Pollutant Discharge Elimination System (NPDES)

EPA Toxicity Spreadsheet Statistical Tool

This NPDES WET Statistical Spreadsheet Tool was developed to analyze valid acute or chronic toxicity test data using EPA statistical approaches. The results generated by the spreadsheet can be used by NPDES permit writers for reasonable potential (RP) evaluations in accordance with EPA’s Technical Support Document Water Quality-based Toxics Control (TSD; EPA/505/2-90/001, March 1991), as well as EPA’s Test of Significant Toxicity Document (TST; EPA 833-R-10-003, June 2010), and for NPDES WET compliance determinations. NPDES permittees and toxicity testing laboratories may also find the spreadsheet useful when analyzing valid toxicity test data.

Disclaimer: Note that neither the EPA nor any of its employees assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information disclosed. Furthermore, the EPA Toxicity Spreadsheet Statistical Tool is supplied “as-is” without guarantee or warranty, expressed or implied, including without limitation, any warranty of merchantability or fitness for a specific purpose.

  • EPA Toxicity Spreadsheet Statistical Tool (xlsm)
  • Factsheet on the EPA Toxicity Spreadsheet Statistical Tool (pdf) (516.08 KB)

<< Return to NPDES Whole Effluent Toxicity (WET) Online Training Course

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)
      • Peak Flows
      • Integrated Planning
    • National Pretreatment Program
      • Standards and Requirements
      • Roles and Responsibilities
      • Events, Training and Webinars, and Publications
    • Pesticide Permitting
    • Stormwater
      • 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 January 3, 2025
  • Assistance
  • Spanish
  • Arabic
  • Chinese (simplified)
  • Chinese (traditional)
  • French
  • Haitian Creole
  • Korean
  • Portuguese
  • Russian
  • Tagalog
  • Vietnamese
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshot
  • Grants
  • No FEAR Act Data
  • Plain Writing
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data
  • Inspector General
  • Jobs
  • Newsroom
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions
  • Site Feedback

Follow.