The federal Clean Water Act (CWA or Act) requires a permit for “any addition of any pollutant to navigable waters from any point source.” 33 U.S.C. 1362 (12) (A). On November 6, 2019, the US Supreme Court (Supreme Court) heard oral argument in County of Maui v. Hawai’i Wildlife Fund, No. 18-260. The question before the Supreme Court is whether the CWA requires a National Pollutant Discharge Elimination System (NPDES) permit for a discharge of a pollutant that is released from a point source to groundwater, travels through groundwater, and ultimately reaches navigable waters.

The answer may turn on the meaning of the word “from” in the statute. If “from” means “directly from the point source to navigable waters,” no permit is required and the County would win. If the term “from” means that the discharge originates at a point source and is subsequently delivered to navigable waters via groundwater, a permit is required and the plaintiff environmental groups would win.

The County injected three to five million gallons of treated wastewater daily for years into four injection wells located a half-mile inland from the Pacific Ocean, without a NPDES permit. The wastewater makes its way through injection well pipes that carry effluent about 200 feet underground to groundwater that migrates to the Pacific Ocean, a navigable water under the Act.

The Ninth Circuit held that, while groundwater is neither a point source nor a navigable water under the CWA, the indirect discharge through groundwater to the Pacific is “fairly traceable,” and the “functional equivalent of a discharge” subject to regulation under the CWA.  Accordingly, the Ninth Circuit held that the County’s injections required an NPDES permit. Hawai’i Wildlife Fund et al v. County of Maui, 886 F.3d 737 (9th Cir. 2018). Relying on the late Justice Scalia’s plurality opinion in United States v. Rapanos, 547 U.S. 715, 126 S.Ct. 2208, 165 L.Ed2d (2006), the Ninth Circuit rejected the County’s argument that a point source must discharge directly into navigable waters to trigger permitting requirements under the CWA, holding instead that it is enough for the discharge to come from a point source (here, the injection well pipes).

At oral argument before the Supreme Court, the County posited that “[t]he question is where the line falls between the CWA’s federal point source program and its state law non-point source program. And the answer is in the text. The text defines a point source as a discernable, confined and discrete conveyance, and it thereby makes clear that the trigger point for point source permitting is not where a pollutant comes from but how it reaches navigable waters.” Nov. 6 Tr. at 3. Requiring a permit for groundwater delivery from a point source would eliminate any “meaningful role for the non-point source program,” according to the County. The County also pointed out that “after the fact” tracer dye studies designed to determine the fate of injected material would not provide regulatory certainty about who must apply for a permit to avoid steep CWA penalties for non-compliance.

The environmental groups argued that “from” meant “from a point source,” not “directly from” a point source, analogizing that “[w]hen you buy groceries, you say they came from the store, not from your car, even though that is the last place they were before they entered the house.” Nov. 6 Tr. at 33. They further argued that science allows well-defined traceability, so that the number of permits required would not be extraordinary if permits were required for point-source-to-groundwater-to navigable-water discharges, and suggested that the concept of proximate cause would also limit the situations where permits would be required.

The federal government, reversing the position it took before the Ninth Circuit, agreed with the County, and argued in its amicus brief that, while the CWA permitting regime excludes groundwater, several other federal statutes address protection of groundwater, and many states regulate groundwater.  While the government referenced EPA’s April 19, 2019 Interpretive Statement on discharges to groundwater, which states that groundwater discharges do not require an NPDES permit, there was no suggestion by the government that EPA’s Interpretive Statement was entitled to deference by the Court under the Chevron doctrine.

Justice Sonia Sotomayor distinguished other statutes governing groundwater as addressing groundwater “after the fact” of pollution. “This statute [CWA] is preventative. We want to avoid having to clean it up. That’s why we give a permit.” Nov. 6 Tr. at 27. Chief Justice John Roberts asked whether, under the County’s and government’s argument, “any little bit of groundwater [between a point source and navigable waters] is enough to break the chain?” and eliminate the requirement for a permit. Nov. 6 Tr. at 24. Justice Elena Kagan commented that, “[Y]ou’ve just provided a roadmap. You know, put your pipe underground.” Nov. 6 Tr. at 25-26.

Justice Samuel Alito postulated that “the ordinary family out in the country that has a septic tank” and “not a lot of money” would buy the septic system “from the lowest cost provider and the lowest cost installer,” which could result in a shoddy installation. Nov. 6 Tr. at 40-41.  Justice Alito was concerned that, under the environmental groups’ reading of the CWA, the family would have an unpermitted leaking tank in violation of the statute, and could be “subject to all the penalties that go with that for every day of the violation.”  Justices Robert, Breyer, Kavanaugh, and Gorsuch expressed similar concerns.

The justices seemed interested in finding a middle ground that would protect water but not overwhelm the permitting program or small sources, expressing concern about the potential for polluters to evade regulation if the County’s and government’s reading of the CWA were adopted. Nov. 6 Tr. at 9.

This case has raised issues about the cooperative federalism that is the basis of the CWA. A decision for the County could limit citizens’ suits challenging certain CWA violations. A decision for the environmental groups could require NPDES permits for discharges from water supply, sanitation, and flood control services, among others, with far-reaching effects.

We are tracking further developments and will provide updates.