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Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

Alternate Test Procedures

When performing Clean Water Act (CWA) monitoring for National Pollutant Discharge Elimination System (NPDES) compliance, only approved analytical methods identified in 40 CFR Part 136 may be used to analyze for regulated constituents.

Parties interested in modifying one of these approved methods, or seeking to use a new method not in Part 136, must apply to use the alternate test procedure (ATP) in the Region in which the discharging facility is located. Applications are submitted to the Region through the State discharge monitoring permitting office. They are reviewed according to the requirements and procedures set forth in 40 CFR Part 136.5.

CWA Analysis and Sampling Procedures, Final Methods Update Rule (MUR), dated May 18, 2012, and found in "Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the CWA; Analysis and Sampling Procedures," approves several new or revised analytical methods, or test procedures for measuring regulated pollutants in wastewater. These methods, published by EPA, voluntary consensus organizations, such as ASTM International and the Standard Methods Committee, or commercial entities, provide increased flexibility for the regulated community and laboratories in their selection of analytical methods for use in CWA programs.

Additional information on the ATP application process may be found on EPA's Clean Water Act Analytical Methods webpage. This website includes instructions in how to apply for ATPs.

Contact Information

Roseanne Sakamoto (sakamoto.roseanne@epa.gov)
Steve Remaley (remaley.steve@epa.gov)

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