Methods Update Rules
The EPA periodically updates the list of approved methods to reflect advances in technology, refine quality assurance and quality control requirements, and provide entities more choices of approved compliance monitoring methods.
On this page:
Current Action
Proposal for Methods Update Rule 22 - 2024
The EPA plans to propose a new Methods Update Rule (MUR), MUR 22, in late 2024, as allowed under the Clean Water Act (CWA). This MUR is not a “routine MUR” because it will propose new parameters and methods. The EPA intends to propose new methods for the following:
- PFAS Method 1633 (the result of a DoD collaboration).
- Adsorbable organic fluorine (AOF) Method 1621.
- Polychlorinated biphenyl (PCB) congeners Method 1628.
The rule may also include other parameters proposed by Voluntary Consensus Standard Bodies (VCSB) as is consistent with the National Technology Transfer Act. The EPA anticipates proposing VCSB methods for measuring PFAS, peracetic acid, and hydrogen peroxide, assuming the VCSB provide adequate validation data. The EPA is not considering method revisions or Alternate Test Procedures that would be addressed more routinely in a routine MUR.
Recent Action
Routine Methods Update Rule 2 - 2023
The EPA has promulgated a final routine MUR, rMUR 2, as allowed under the CWA, on April 16, 2024. In rMUR 2, the EPA approved:
- Revised EPA bacteria methods.
- New or revised methods published by voluntary consensus standard bodies, such as ASTM International and the Standard Methods Committee.
- Methods reviewed under the Alternate Test Procedures (ATP) program.
Documents
All supporting materials for rMUR 2 can be found on the EPA’s docket at regulations.gov. The Docket Number is EPA-HQ-OW-2022-0901.
- Final rMUR 2 Federal Register Notice (April 16, 2024).
- Fact Sheet; Final Rule: Clean Water Act Methods Update Rule for the Analysis of Effluent (pdf) .
Background Information
Additional Information
For further information on MURs generally, please contact Tracy Bone (bone.tracy@epa.gov) or 202-564-5257.