Court Rules County of Maui Must Obtain Permit Under CWA

Court Rules County of Maui Must Obtain Permit Under CWA

A Hawaii federal judge has concluded that the County of Maui must obtain a permit under the Clean Water Act (CWA) for its wastewater treatment facility...

A Hawaii federal judge has concluded that the County of Maui must obtain a permit under the Clean Water Act (CWA) for its wastewater treatment facility, resolving a lawsuit that has lasted for nearly a decade. In reaching her decision, U.S. District Judge Susan Oki Mollway applied the factors established by the U.S. Supreme Court in County of Maui, Hawaii v. Hawaii Wildlife Fund.  

CWA Dispute Over Wastewater

The suit centers on four wells owned and operated by the County of Maui (County). The Lahaina Wastewater Reclamation Facility (LWRF) is the principal municipal wastewater treatment plant for West Maui and processes four million gallons of sewage per day from approximately 40,000 people. 

The wells operate under permits that authorize injection of wastewater underground pursuant to the federal Safe Drinking Water Act, but the County does not have a NPDES permit. In June 2013, the U.S. Environmental Protection Agency (EPA), the Hawaii Department of Health (HDOH), the U.S. Army Engineer Research and Development Center, and researchers at the University of Hawaii conducted a study on Wells 2, 3, and 4 to gather data on, among other things, the “hydrological connections between the injected treated wastewater effluent and the coastal waters.” The study found “64 percent of the treated wastewater injected into [Wells 3 and 4] currently discharges [into the ocean].” Several organizations filed suit against the County, alleging that the County was violating the CWA by “discharging effluent through groundwater and into the ocean without the [NPDES] permit required.” 

The CWA prohibits the discharge of any pollutants, including dredged or fill material, to “navigable waters” without first obtaining a permit under the National Pollutant Discharge Elimination System (NPDES). Prior to the Supreme Court’s decision in Maui County, the federal courts of appeals were deeply divided on the question of whether a CWA “discharge of a pollutant” occurs when pollutants are released from a point source to groundwater and migrate through, or are conveyed by, groundwater to navigable waters.

While recognizing that the LWRF was not discharging wastewater directly into the Pacific Ocean, the district court ruled that an NPDES permit was necessary because a “discharge into the groundwater below the LWRF is functionally equivalent to a discharge into the ocean itself.” On appeal, the Ninth Circuit affirmed the result but articulated a different approach, concluding that an NPDES permit was necessary because pollutants were “fairly traceable from the point source to a navigable water.”

Supreme Court’s Functional Equivalent Test

In County of Maui, the Supreme Court held that permits are required under the CWA when there is a functional equivalent of a direct discharge. “We hold that the statute requires a permit when there is a direct discharge from a point source into navigable waters or when there is the functional equivalent of a direct discharge,” Justice Stephen Breyer wrote on behalf of the Court.

The Supreme Court’s “functional equivalent of a direct discharge” standard requires a permit for discharge from any point source directly into navigable waters, and from point sources when the discharge “reaches the same result through roughly similar means.”  The Court noted that time and distance will be the most important factors in most cases, but listed seven factors that should be considered in determining whether the discharge comes “from” a point source: (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, (7) the degree to which the pollution (at that point) has maintained its specific identity.

Court Rules Maui Must Obtain NPDES Permit

On remand, the district court was tasked with determining whether the LWRF’s placement of wastewater into injection wells from which the wastewater flows to the Pacific Ocean is the “functional equivalent of a direct discharge” from the LWRF into the Pacific Ocean. After applying the factors set forth by the Supreme Court, Judge Mollway concluded that there has been the functional equivalent to a direct discharge. Accordingly, she further ruled that ruling that the County is and was required to have an NPDES permit.

“Based on the undisputed evidence that the County discharged tens of thousands of gallons of wastewater from the LWRF into the Pacific Ocean on a daily basis at a few monitored seep vents, and balancing the factors set forth by the Supreme Court, as well as the additional volume factor that this court added, this court concludes that the LWRF must have an NPDES permit,” Judge Mollway wrote.  “The discharge from the County’s injection wells into the groundwater and ultimately into the ocean is the functional equivalent of a direct discharge such that it triggers the NPDES permit requirement.”

The court specifically found that the time and distance factors, which the Supreme Court identified as most important factors, as well as the relative-amount-of-pollution-entering-the-water and the specific-identity factors, weighed in favor of applying the NPDES permit requirements. 

On the other hand, it found the nature-of-material and dilution/chemical-change factors favored not requiring a permit. The manner-by-or-area-in- which-the-pollutant-enters-the-water factor was neutral, according to Judge Mollway. She also added another factor — the raw-volume-of-pollutant factor — which weighed in favor of requiring a permit.

In reaching her decision, Judge Mollway rejected the County’s argument that additional studies were needed to evaluate the source and environmental impact of pollutants found in groundwater seeps. According to the court, "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."

"It is impossible to track each finger of water percolating through groundwater or sand or dirt," Judge Mollway added. "Indeed, if a party could not prevail without establishing the transit time for every trickle of liquid through groundwater, then no challenge involving groundwater could ever be successful."

Key Takeaway

The court’s decision that wastewater discharged to groundwater via unpermitted injection wells is "the functional equivalent" of a direct discharge to navigable waters despite the significant physical migration and passage of time required for the contamination to reach those waters has potentially subjected such dischargers to Clean Water Act NPDES permitting requirements for the first time.  Businesses using such injection wells or with any potential discharges to groundwater that may lead to navigable waters should remain attuned to further developments and contact me or a Scarinci Hollenbeck attorney to discuss any questions they may have.

If you have questions, please contact us

If you have any questions or if you would like to discuss the matter further, please contact me, Dan McKillop, or the Scarinci Hollenbeck attorney with whom you work, at 201-896-4100.


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AboutDaniel T. McKillop

Dan McKillop has more than fifteen years of experience representing corporate and individual clients in complex environmental litigation and regulatory proceedings before state and federal courts and environmental agencies arising under numerous state and federal statutes.Full Biography

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