In reaching its decision, the Court declined to assign any deference to the Interpretive Statement, finding the Agency’s interpretation was “neither persuasive nor reasonable” because it “would open a loophole allowing easy evasion of the statutory provision’s basic purposes.”4 Instead, the Court resolved what it described as a linguistic question, finding that a permit is required both for a direct discharge and “the functional equivalent of a direct discharge.”5 Although affording more protection than the Agency’s Interpretive Statement, the Court’s opinion stopped short of fully embracing the Ninth Circuit’s decision below that would have allowed EPA to exert permitting authority over pollutants that are “fairly traceable” from point sources.6
The Court’s holding did not establish a bright-line rule; functionally, it came closer to striking a middle ground between environmentalists’ position and that of the federal government. Perhaps anticipating the difficulties facing the agency and lower courts in applying its holding, the Court offered several factors that may be relevant to determining whether a given discharge is the functional equivalent of a direct discharge.7 Time and distance will be the most important factors in “most cases,” whereas other relevant factors include the nature of the material through which the pollutant travels, the extent to which the pollutant is diluted or changed chemically as it travels, the amount of the pollutant that enters navigable waters relative to the discharged amount, the manner by or area in which the pollutant enters navigable waters, and the degree to which the pollutant has maintained its specific identity.8 Discretionary in nature, these factors will require EPA, judges and others interpreting the Clean Water Act’s permitting requirements to perform a balancing test to determine whether a permit is needed in many situations.
The Court also expressly left room for lower courts and EPA to further refine the scope of permissible federal jurisdiction over groundwater pollution, so long as any such interpretations remain in line with statutory objectives, i.e., avoid “creat[ing] serious risks either of undermining state regulation of groundwater or of creating loopholes that undermine the statute’s basic federal regulatory objectives.”9 In the meantime, discharges from a range of activities may once again be subject to federal regulation, including leaks from sewage collection systems, septic system discharges, discharges from treatment systems (e.g., constructed wetlands), spills and accidental releases, process wastewater applied to agricultural land and coal ash impoundment seepage.10
1 Cnty. of Maui v. Hawai’i Wildlife Fund, et al., 590 U.S. __ (2020), https://www.supremecourt.gov/
opinions/19pdf/18-260_i4dk.pdf, at 1. Notably, the majority opinion included Chief Justice Roberts and Justice Kavanaugh, offering a potential preview of the Court’s future environmental decisions.
2 U.S. Envtl. Protection Agency, Interpretive Statement on Application of the Clean Water Act National Pollutant Discharge Elimination System Program to Releases of Pollutants From a Point Source to Groundwater, 84 Fed. Reg. 16810, 16821-23 (Apr. 12, 2019) available at https://www.govinfo.gov/content/pkg/FR-2019-04-23/pdf/2019-08063.pdf (collecting cases).
3 Id. at 16817-19.
4 Cnty. of Maui, supra note 1, slip op. at 12.
5 Id. at 15 (emphasis in original).
6 Id. at 9-10.
7 Id. at 16.
8 Id.
9 Id. at 17.
10 Id. at 13 n.8 (Alito, J., dissenting) (citing 84 Fed. Reg. at 16812).
