The County of Maui is being taken to the Supreme Court by a number of advocacy groups, led by the Hawaii Wildlife Fund, after a study showed that wastewater from the Lahaina Wastewater Reclamation Facility injected into groundwater could be traced into the Pacific ocean. The Clean Water Act prohibits the discharge of pollutants from a point source into navigable waters, unless an authorized National Pollutant Discharge Elimination System (NPDES) permit has been obtained – a permit that the Lahaina Facility fails to have.
The argument on whether the County of Maui needed the NPDES permit or not depends on the interpretation of the CWA. While the definition of ‘point source’ incorporates a lengthy list of means (33 U.S.C. 1362(14)), it does not consider groundwater. In fact, under the CWA there is no direct mention regarding groundwater and its role in dispersing polluted waters into navigable waters. The overall lack of consideration for the connectivity of water sources in the CWA has led to numerous cases regarding its various interpretations and therefore the extent of its jurisdiction. This has led to the ultimate question of whether a CWA permit is required when a pollutant originates from a point source, but is conveyed to navigable waters by a non-point source. It is this question that the Supreme Court has granted certiorari to determine whether the County of Maui has been acting unlawfully in its wastewater discharges.
The Lahaina Wastewater Facility injects treated wastewater, known as effluent, into underground injection control wells (UIC). Once injected into wells, the effluent mixes with groundwater, dispersing and eventually migrating to other sources of water including to open ocean. These facts are undisputed and the County conceded that the UIC wells were indeed ‘point sources’ under the CWA. However, the County of Maui argues that groundwater is not constituted under the CWA’s ‘waters of the United States’. As such, the County argued that if a pollutant from a point source reached groundwater, being a non-point, and consequently discharged elsewhere, the pollutant is no longer a discharge by a point source.
An interpretation of this kind would present groundwater sources as a loophole for pollutant discharge. The 9th Circuit previously opted against this interpretation and held the County liable under the CWA for discharge of pollutants from point source, relying in part on Justice Scalia’s plurality opinion in Rapanos v. United States, 547 U.S. 715 (2006) stating that he recognized that addition of any pollutant to navigable waters falls under the CWA. The County, however, recalled rulings from the 5th and 7th Circuit in which the CWA does not prohibit addition of pollutant to groundwater even if it is hydrologically connected to the surface (Rice v. Harken Exploration Co., 250 F.3d (5th Cir. 2001) and Vill. of Oconomowoc Lake v. Dayton Hudson Corp., 24 F .3d 962 (7th Cir. 1992)). As such, the primary issue at hand is the interpretation and classification of groundwater and its connectivity under the CWA.
To help clarify the importance of protecting groundwater under the CWA, ASLO has joined a group of aquatic scientists and scientific societies in submitting a brief as Amici Curiae in support of Hawaii Wildlife Fund. The brief elaborates on the hydrology of groundwater, how it controls water quantity and quality at the surface, connects to point sources and surface waters, and creates pathways for pollution dispersal. Scientific methods and models testing hydrological connectivity of groundwater and pollutant distribution that support the 9th District’s decision are explicitly described. Furthermore, the brief highlights the County of Maui’s failure to accurately track pollution, consequently disregarding hydrological reality and best-practice scientific applications. The brief argues that ' the Clean Water Act’s mandate to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters, 33 U.S.C. § 1251(a), can only be met if the scientific reality of connections between point sources and surface waters through groundwater is taken into account'.
The plurality of the CWA interpretations has long been causing confusions over its implementation and enforcement (see Sponberg, 2009), leaving the question of whether water bodies such as isolated wetlands, ephemeral streams and now groundwater are covered by the CWA. Decisions made in the case County of Maui v. Hawaii Wildlife Fund could provide a new legislative protection for groundwater, tightening regulations of pollution and closing this loophole. The hope is that the Supreme Court hearing on November 6th will provide desperately needed clarifications regarding the CWA.