On January 14, 2021, the United States Environmental Protection Agency (EPA) released final guidance for making case-by-case determinations on the need for federal permitting of surface water discharges through groundwater. The guidance applies the United States Supreme Court’s recent decision in County of Maui v. Hawaii Wildlife Fund, 140 S. Ct. 1462 (2020). Although a draft of the guidance was released for public comment in December 2020, EPA finalized the guidance with minimal changes.
In Maui, the Court held that a discharge from a point source to surface waters through groundwater requires a National Pollutant Discharge Elimination System (NPDES) permit when the addition of pollutants to surface water is the “functional equivalent of a direct discharge.” The Court provided a non-exclusive list of seven factors to be considered by EPA or the permitting authority in determining whether a conveyance of pollutants through groundwater is the “functional equivalent of a direct discharge.” These seven factors include:
- Transit time;
- Distance traveled;
- The nature of the material through which the pollutant travels;
- The extent to which the pollutant is diluted or chemically changed as it travels;
- The amount of pollutant entering the navigable waters relative to the amount of the pollutant that leaves the point source;
- The manner by or area in which the pollutant enters the navigable waters; and
- The degree to which the pollution (at that point) has maintained its specific identity.
A detailed analysis of these factors can be found here in a previous Client Alert.
EPA’s final guidance identifies one additional factor for consideration when evaluating whether and how to perform a “functional equivalent” analysis—the “design and performance of the system or facility from which the pollutant is released.” EPA observed that, although this factor was not identified by the Court in Maui, “inquiries concerning design and performance are important and relevant and are routinely considered by permitting authorities in the administration of the NPDES permit program.”