EPA Considers Permitting Discharges to Groundwater Under the Clean Water Act

Source: AGC of America Environmental Observer – March 30, 2018

AGC Seeks Input from Members on Potential Impact to Their Operations

The U.S. Environmental Protection Agency (EPA) is accepting public comment until May 21 on several topics related to the question of whether the federal government should use the Clean Water Act (CWA) National Pollutant Discharge Elimination System (NPDES) program to regulate discharges to (or through) groundwater that hydrologically connects to a “Water of the United States” (WOTUS). AGC is seeking more information from members on how this EPA action may impact contractors that own/operate stormwater infrastructure that “treats” or “stores” water runoff. This would include features that infiltrate stormwater or process water underground such as injection wells, underground tanks, surface water impoundments, retention or detention ponds, artificially constructed wetlands, treatment lagoons, or groundwater recharge and reuse systems.

EPA’s Federal Register notice points out that the courts have approached the question in varying ways. Over the years, and in varied settings, EPA has stated that such pollutant discharges may be subject to CWA requirements. But in the absence of clear and consistent nationwide requirements, the agency has made fact-specific, case-by-case determinations.

Some AGC members report that they use underground storage to allow incoming stormwater runoff to exfiltrate into underlying soils. Under current federal law, if an infiltration best management practice (BMP) is deeper than its widest surface dimension, or has a subsurface fluid distribution system, then it will likely be considered a Class V stormwater drainage well that is regulated under EPA’s Underground Injection Control (UIC) program at 40 CFR Parts 144 – 147, required by the Safe Drinking Water Act. See the AGC “Discussion DRAFT” document that summarizes the minimum federal requirements and the relevant language in EPA’s federal NPDES Construction General Permit. What EPA is wrestling with now is whether the agency should also apply the CWA NPDES permit program to discharges to groundwater where there is a direct hydrologic connection to jurisdictional water. EPA has asked for feedback on which connections are considered “direct,” recognizing the uncertainties associated with that term.

AGC Member Input NEEDED

Through public input, AGC and its members have an opportunity to inform a potential future federal regulatory action. Comments are due to EPA by May 21, 2018. Please respond to Leah Pilconis at pilconisl@agc.org by April 21.

  1. How would your company be impacted if EPA were to assert CWA jurisdiction over releases to groundwater?
  2. If EPA has the authority to subject such releases to CWA NPDES permitting, are they already addressed adequately through existing state statutory or regulatory programs or through other existing federal regulations and permit programs?

Background: Recent Ninth Circuit Decision

This EPA action stems from the U.S. Court of Appeals for the Ninth Circuit’s recent opinion in Hawaii Wildlife Fund v. County of Maui (County). The court concluded that the County’s underground injection control wells are “point sources” that “discharged” pollutants into groundwater that acted as an unconfined pathway that eventually reached the Pacific Ocean—a “navigable water” (881 F.3d 754 (9th Cir. 2018, 2/1/2018)). The wells therefore required NPDES permit coverage, per the Clean Water Act. The court based its decision on the “conduit theory” that unconfined groundwater can act as a point source if it conveys pollutants from a point source into a navigable “water of the United States” (WOTUS). Specifically, the court held that (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 to navigable waters; (3) the pollutant levels reaching the navigable water are more than de minimis. Read the full opinion here.

Please direct your comments and any questions to Leah Pilconis at pilconisl@agc.org or (703) 837-5332.