vvEPA

FACT SHEET

Federal Register Action: Expedited Approval of Alternative Test Procedures
for the Analysis of Contaminants Under the Safe Drinking Water Act;

Analysis and Sampling Procedures

EPA is approving two alternative test procedures for contaminants listed in the drinking water
regulations. These procedures have been determined by the Agency to be as effective as the methods
already established in the regulations for the same contaminants. EPA has used its streamlined
approval authority to make these two alternative methods available under the Safe Drinking Water Act
(SDWA).

Summary of Action

EPA has evaluated two testing methods for contaminants listed in the regulations and determined
them to be as effective as methods already established in the regulations for those contaminants. The
Agency is using its streamlined method approval authority to make these two optional, alternative
methods listed in Tables 1 and 2 available for determining contaminant concentrations in samples
collected under SDWA.

Table 1: EPA Method

Method1

Contaminant(s)/Parameter(s)

537.1, version 1.0

Perfluorobutane Sulfonate (PFBS)

537.1, version 1.0

Perfluorohexane Sulfonate (PFHxS)

537.1, version 1.0

Perfluorononanoate (PFNA)

537.1, version 1.0

Perfluorooctanesulfonic Acid (PFOS)

537.1, version 1.0

Perfluorooctanoic Acid (PFOA)

537.1, version 1.0

2,3,3,3-Tetrafluoro-2-
(heptafluoropropoxy)propanoate
(HFPO-DA or GenX Chemicals)

Approved as alternative testing method to support initial PFAS monitoring (for monitoring-frequency
determinations) until April 26, 2027, as described at 40 CFR 141.902(b)(1) [Monitoring requirements
for PFAS - Initial monitoring].

Table 2: Vendor-Developed Methods

Method

Contaminant(s)/Parameter(s)

e-sens AMCD Method

Free Chlorine

e-sens AMCD Method

Total Chlorine

States that previously conducted PFAS monitoring using version 1 EPA PFAS method 537.1 and the
water systems in those states will be able utilize that prior monitoring data to satisfy the initial
monitoring requirements for the PFAS drinking water regulation.

EPA 815-F-25-003

Page 1 of 2

January 2025


-------
The approval of the vendor developed method for automated measurement of chlorine provides for a
broader selection of analytical methods for water systems and laboratories to use, thereby reducing
monitoring costs while maintaining public health protection.

Additional Information and Copies

You can view or download the complete text of the Expedited Method Approval Federal Register final
action (https://www.epa.gov/dwanalyticalmethods).

A listing of the methods approved using the expedited approval process can also be downloaded from
the same website.

You can learn more about the Expedited Method Approval Process for drinking water and the
alternative testing methods approved under the program by using the online contact form at
epa.gov/safewater or contacting Teresa Wells, Technical Support Branch (MC-140), U.S. Environmental
Protection Agency, Office of Water, Office of Ground Water and Drinking Water, 26 West Martin
Luther King Drive, Cincinnati, Ohio 45268; (e-mail wells.teresa@epa.gov).

EPA 815-F-25-003

Page 2 of 2

January 2025


-------