On September 16, 2021, EPA rescinded the Trump administration’s guidance for determining when a discharge through groundwater requires a permit.  Going forward, “EPA will continue to apply site-specific, science-based evaluations to determine whether a discharge from a point source through groundwater that reaches jurisdictional surface water requires a permit under the Clean Water Act.”

Supreme Court Case
In April 2020, the US Supreme Court issued County of Maui v. Hawaii Wildlife Fund, which said a permit is required “if the addition of the pollutants through groundwater is the functional equivalent of a direct discharge from the point source into navigable waters.”

Trump Guidance Rescinded
State environmental agencies, operating under an EPA approved program, issue most water discharge permits.  In the final days of the Trump administration, EPA issued the guidance to assist permitting agencies in applying the “functional equivalent” test.

The current EPA characterized that guidance as “inconsistent with EPA’s authority to limit pollution discharges to our waters.”

In rescinding the guidance, EPA did not commit to issuing new guidance; rather, it is “evaluating appropriate next steps.”  Until further EPA action, application of the “functional equivalent” test will be on a “site-specific” basis.

To see EPA’s news release announcing the rescission, https://www.epa.gov/newsreleases/epa-rescinds-previous-administrations-guidance-clean-water-act-permit-requirements