vvEPA

Office of Water
EPA 820-F-23-002
January 2023

Proposed Rule: Clean Water Act Methods Update Rule
for the Analysis of Effluent

EPA is seeking public comment on a proposed rule that would update its list of approved
methods for measuring pollutants in wastewater and waterbodies under the Clean Water Act.

Industrial facilities, municipal wastewater treatment plants, and state governments use
approved methods to identify the types and amounts of pollutants regulated under the Clean
Water Act. This action proposes to add some new methods to Part 136 of Title 40 of the Code
of Federal Regulations (CFR) and makes minor editorial or procedural changes to some existing
methods that are already promulgated in 40 CFR Part 136.

How does this action help the regulated community?

Often, regulated entities have a choice in deciding which approved method they will use to measure a
pollutant because more than one approved method is available under 40 CFR Part 136. This rulemaking
would increase flexibility by providing additional methods from which to select. New methods added
under the Alternate Test Procedure (ATP) program reflect innovative technologies that are cheaper,
faster, or greener than the other approved methods for that same parameter. When final, this rule
would impose no regulatory requirements or costs on any person or entity. The use of alternate
methods is voluntary.

Is EPA required to establish analytical methods?

Yes, CWA Section 304(h) requires EPA to establish analytical methods to measure pollutants in NPDES
permit applications and for reports required under NPDES permits. These CWA methods are found in
40 CFR Part 136 and are used to implement the NPDES program. This action proposes minor updates to
40 CFR Part 136.

What would EPA's updates change?

The proposed changes are minor technical changes and clarifications to improve existing methods, new
and/or revised methods published by voluntary consensus standard bodies (such as ASTM
International and the Standard Methods Committee) that EPA seeks to publish in Part 136, and
methods EPA has reviewed under its ATP program and found to be comparable to one or more
methods currently in Part 136.

Where can I find more information?

You can view the Federal Register notice and supporting documents for the proposed rule at
http://www.regulations.gov under Docket ID: EPA-HQ-OW-2022-0901. EPA has also provided a link to
the Federal Register on the Clean Water Act Analytical Methods website at: https://www.epa.gov/cwa-
methods. You may also contact Tracy Bone at (202) 564-5257, or at bone.tracy@epa.gov.

Page 1 of 1


-------