After nearly a decade of litigation between the County of Maui and environmental groups, a Hawaii district court has ruled that the County, as operator of a wastewater reclamation facility that injects a wastewater stream into groundwater via a well, must obtain a Clean Water Act (CWA) permit because of the effect the injected material eventually has on a CWA-regulated surface water. The decision comes 16 months after the Supreme Court issued its landmark ruling in County of Maui v. Hawaii Wildlife Fund et al., in which the Court held that a CWA permit may be required for point source pollutants that reach jurisdictional waters through groundwater if the pathway through groundwater is the “functional equivalent” of a direct discharge from a point source to jurisdictional waters. However, the district court appears to have set a very low bar for functional equivalence, which if adopted by courts broadly, could dramatically increase the number and types of facilities subject to permitting under the CWA.

After remand from the Supreme Court, the issue before the district court was whether the County’s placement of water into injection wells from which wastewater flows via groundwater into the Pacific Ocean one half-mile away is the “functional equivalent of a direct discharge.” Judge Mollway utilized the non-exhaustive list of “functional equivalence” factors provided by the Supreme Court: (1) transit time, (2) distance traveled, (3) the nature of the material through which the pollutant travels, (4) the extent to which the pollutant is diluted or chemically changed as it travels, (5) the amount of pollutant entering the navigable waters relative to the amount of the pollutant that leaves the point source, (6) the manner by or area in which the pollutant enters the navigable waters, and (7) the degree to which the pollution (at that point) has maintained its specific identity. The court also considered two other factors: “the manner by or area in which the pollutant enters the navigable waters” and impact on the ecosystem.

Ultimately, the court found that five of those nine factors weighed in favor of requiring a CWA permit. Notably, scientific studies could only conclusively establish the path of two percent of the wastewater at issue, but both parties agreed that all of the wastewater placed into the injection wells eventually finds its way to the Pacific Ocean. The court concluded that “the difficulty of detecting and measuring what may be the diffuse discharge of much of the remaining wastewater that reaches the ocean does not nullify the Clean Water Act’s NPDES permit requirements.”

Although the functional equivalence test is highly fact-dependent, this decision signals a warning to facilities that do not discharge directly to navigable waters of potential increase in scrutiny from regulators or interested third parties (i.e., citizen suits). KMCL attorneys are available to address your questions about the significant implications of this new line of case law.