An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Drinking Water Requirements for States and Public Water Systems

Long Term 2 Second Round Source Water Monitoring and Bin Placement Memo

The Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) applies to all public water systems served by a surface water source or public water systems served by a ground water source under the direct influence ofsurface water. This memo is regarding the LT2ESWTR  second round of monitoring and bin placement.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.