On April 23, 2019, the Environmental Protection Agency (EPA) made available for public comment an Interpretative Statement issued on April 12, 2019, addressing whether the Clean Water Act (CWA) National Pollutant Discharge Elimination System (NPDES) permit program applies to releases of a pollutant from a point source to groundwater. See 84 FR 16810. In February 2018, the EPA had issued a notice in the Federal Register requesting public comment on the EPA’s previous statements that discharges to groundwater with a direct hydrologic connection to jurisdictional surface waters are subject to the CWA. In a departure from its previous position, the agency now concludes in its April 12 Interpretive Statement that the CWA excludes from NPDES program coverage all releases of pollutants from a point source to groundwater, regardless of a hydrologic connection between the groundwater and jurisdictional surface water. The EPA is soliciting additional public input on this issue.

According to the EPA, this is the first time the agency has issued guidance focused exclusively on whether NPDES permits are required for releases of pollutants to groundwater that reach surface water. The agency acknowledged “a mixed record of prior agency statements addressing this issue and a split in the federal circuit courts regarding the application of the NPDES permit program to releases of pollutants to groundwater that reach jurisdictional surface waters.” 84 FR 16810, 16811.

The US Supreme Court recently granted a petition for writ of certiorari in Hawai’i Wildlife Fund v. Cty. of Maui, 886 F.3d 737 (9th Cir. 2018), in which the Ninth Circuit held that the CWA applied where pollutants were discharged into groundwater and eventually entered the Pacific Ocean. The Ninth Circuit found the County of Maui liable under the CWA because “(1) the County discharged pollutants from a point source, (2) the pollutants are fairly traceable from the point source to a navigable water such that the discharge is the functional equivalent of a discharge into the navigable water, and (3) the pollutant levels reaching navigable water are more than de minimis.” Id. at 749; see also Upstate Forever v. Kinder Morgan Energy Partners, L.P., 887 F.3d 637, 652 (4th Cir. 2018) (holding that “an alleged discharge of pollutants, reaching navigable waters located 1000 feet or less from the point source by means of ground water with a direct hydrological connection to such navigable waters, falls within the scope of the CWA”).The April 12 Interpretive Statement contradicts the amicus brief filed by the United States in the Ninth Circuit County of Maui proceeding, which supported the theory that discharges through groundwater that have a direct hydrologic connection to jurisdictional surface water may be subject to regulation under the CWA. The agency now concludes that “the text, structure, and legislative history of the CWA, as well as the better-reasoned judicial decisions, support the legal conclusion that Congress intended to exclude all releases of pollutants to groundwater from NPDES program coverage, regardless of a hydrologic connection or conveyance to jurisdictional surface water.” 84 FR 16810, 16814.

The EPA clarified in the April 23 notice that the agency’s Interpretive Statement currently applies only outside the Fourth and Ninth Circuits.

Assuming the County of Maui will look to the April 12 Interpretive Statement for support, it will be interesting to see whether the Supreme Court will apply to its analysis the Chevron doctrine, which is more deferential, or the Skidmore doctrine, which says that judicial deference is owed only if the agency interpretation is persuasive.