(December 9, 2020) - The U.S. Environmental Protection Agency (EPA) this week released a proposed guidance memorandum providing information on the application of the U.S. Supreme Court’s decision in County of Maui v. Hawaii Wildlife Fund to the Clean Water Act Sec. 402 National Pollutant Discharge Elimination System (NPDES) program. 

According to EPA, the long-awaited guidance – which even if finalized would not be legally binding – is intended to assist both the regulated community and permitting authorities in determining when a discharge that originates from a “point source” and reaches a jurisdictional “water of the United States” through groundwater is the “functional equivalent” of a direct discharge which requires an NPDES permit. 

After reiterating that several requirements not at issue in the County of Maui case must be met before NPDES coverage is necessary – namely, that a discharge of pollutants originate from a “point source” and actually reach a “water of the United States” – the guidance notes that it is not the responsibility of a facility owner or operator or permitting agency “to prove the absence of a discharge,” and that mere allegations that a discharge reaches a jurisdictional water without supporting documentation are not sufficient to trigger NPDES liability.

The guidance then goes on to directly address application of the Maui decision.  Importantly, EPA notes that historically few permits were issued for discharges reaching “waters of the United States” via groundwater under the Agency’s former case-by-case “direct hydrologic connection” analysis, and that it expects such permits “will continue to be a small percentage” of the overall number of NPDES permits issued following Maui.

The guidance also outlines how, under the seven factors the Maui Supreme Court decision listed as relevant to the “functional equivalent” analysis including transit time and distance traveled, whether or not a system treats, provides uptake of, dilutes, retains, or attenuates pollutants should be considered when determining if a discharge through groundwater is the “functional equivalent” of a direct discharge.

EPA also emphasizes that the Maui factors are not exclusive, and adds as another relevant consideration the “design and performance of the system or facility from which the pollutant is released,” which can affect the time and distance pollutants travel, as well as their chemistry and concentration upon reaching a navigable water.  

Most notably, the guidance states that “if a facility is operating as a runoff management system, such as with stormwater controls, infiltration or evaporation systems or other green infrastructure; or if the facility operates water reuse, recycling or groundwater recharge facilities, and these system components in fact prevent or abate discharges of pollutants to waters of the United States, it may be less likely that an NPDES permit would be required—either because those pollutants do not reach a water of the United States or because the discharge is not a functional equivalent of a direct discharge to a water of the United States.”

The guidance therefore appears to acknowledge the clean water community’s longstanding contention that environmentally beneficial activities such as water reuse and green infrastructure development serve the overall purposes of the CWA and should generally not be subject to onerous NPDES permitting requirements.  

EPA will be taking comments on the draft guidance for 30 days after it is published in the Federal Register.  It is therefore unlikely that the guidance will be finalized before January 20, and it is unclear how the incoming Biden Administration intends to address the issues raised in Maui going forward.

NACWA will be filing comments on the draft guidance, and will continue to keep members informed of any relevant developments as they occur.  In the interim, please contact NACWA’s Chief Legal Counsel, Amanda Aspatore, with any questions.