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Clean Water Act Analytical Methods

Methods Update Rule - 2021

""Rule Summary

EPA finalized specific changes to analytical test procedures that are used by industries and municipalities to analyze the chemical, physical, and biological components of wastewater and other environmental samples that are required by regulations under the Clean Water Act. The changes include:
  • revised EPA methods;
  • new or revised methods published by voluntary consensus standard bodies, such as ASTM International and the Standard Methods Committee;
  • new and updated methods developed by the U.S. Geological Survey;
  • methods reviewed under the Alternate Test Procedures (ATP) program; and
  • minor changes to quality assurance and quality control within individual methods.

Final Rule

You can view the submitted public comments at regulations gov. The Docket Number is EPA-HQ-OW-2018-0826.

Background Information

Additional Information

For further information on the proposed rule, please contact Meghan Hessenauer ( or 202-566-1040.