(October 17, 2017) - The Ninth Circuit Court of Appeals held a hearing on October 12 in Hawaii Wildlife Fund v. County of Maui, a critical case addressing the “conduit” theory of liability under the Clean Water Act (CWA).  This particular appeal arises from a lower court decision that migration of pollutants from a properly permitted underground injection control (UIC) wells operated by NACWA member the County Maui, through groundwater into hydrologically connected navigable waters, violates the CWA.  NACWA filed an amicus brief  in March 2016 urging reversal by the court.

Based on NACWA’s analysis of an audio recording of the hearing, the court seemed to be more receptive to the citizen activist group’s arguments.   The court appeared swayed by a tracer study which showed that treated wastewater from the County's UIC wells mixed with groundwater that traveled approximately 10 months to reach the ocean roughly half a mile south of the plant where it entered the ocean in a diffuse manner along two miles of coastline.  The court asked the plaintiffs if they would argue that CWA liability existed even if the tracer study had shown that only 1% of the point source discharge reached the ocean. The plaintiffs responded that because the CWA is a strict liability statute, liability exists even at that amount.

The plaintiffs also argued that EPA’s position supporting a finding of CWA liability as expressed in its amicus brief should be afforded deference.  In the brief, EPA argues that the CWA permit program should apply to indirect discharges from point sources through groundwater with a “direct hydrological connection” to waters of the United States (WOTUS).

The groundwater conduit theory of liability is popping up in CWA litigation across the country with increasing regularity, with most courts confusing the WOTUS jurisdiction test with the point source test.  In addition to the Ninth Circuit, the theory is on appeal in the Second and Fourth Circuits in very different factual cases.

In strategic anticipation of negative precedent emerging in the Ninth Circuit, NACWA is working with a wide array of stakeholders to secure a solid, positive decision in at least one other circuit, which would result in a split among the circuits. The matter would then be ripe for petition to the US Supreme Court.