Jump to main content or area navigation.

Contact Us

Water: Mercury

Method 1631: Measurement of Mercury in Water

This method allows for the determination of mercury at a minimum level of 0.5 parts-per-trillion and supports measurements for mercury published in the National Toxics Rule and in the Final Water Quality Guidance for the Great Lakes System. Includes Guidance for Implementation and Use of Method 1631 and Revision E to the method, which contain additional and revised requirements.

Revision E, Final Rule

This final rule replaces the currently approved version of Method 1631 and includes revisions that address stakeholder concerns. This revision clarifies quality control and sample handling requirements and allows flexibility to incorporate additional available technologies. This rule also amends the requirements regarding preservation, storage, and holding time for low level mercury samples.

This method replaces the previously approved Method 1631 Revision C.

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


Jump to main content.