Clean Water Act Permits & Groundwater: What You Need to Know

May 16, 2019

Last month, the U.S. Environmental Protection Agency (EPA) attempted to “unmuddy” the question surrounding pollutant discharges to groundwater.

Specifically, they hope to clarify the interpretation of the National Pollutant Discharge Elimination System (NPDES) permit program as described in the Clean Water Act (CWA).

The verdict: the CWA does not regulate point source pollution (pollutants discharged from a specific, single source i.e. a well) releases to groundwater. Therefore, facilities do not require a NPDES permit.

The EPA feels that the U.S. Congress “intentionally chose to exclude releases of pollutants to groundwater from the NPDES program, even if the groundwater eventually flows into regulated surface waters”, i.e. regardless whether the groundwater is hydrologically connected to surface waters.

However, companies are not completely off the hook. Discharges may be subject to individual state regulation “and to EPA under other statutory authorities”, such as the Safe Drinking Water Act, RCRA and CERCLA.

Several conflicting federal court decisions regarding NPDES permits and groundwater forced EPA to address the issue. In February 2018, the agency requested public comments on whether clarification was needed. More than 50,000 comments from a wide range of stakeholders sent a resounding “Yes”!

After a thorough review of prior agency statements on the matter and an analysis of the text, structure, and legislative history of the CWA, the agency reached a decision.

However, this Interpretative Statement does not apply to at least 14 states. In recent verdicts, courts in the Fourth and Ninth Circuits took a different interpretation than that of the EPA. As a result, the EPA decision does not currently pertain to states in those Circuits (see the map below).

EPA Groundwater Map

The Outliers

In the Ninth Circuit, in the case of Hawaii Wildlife Fund v. County of Maui, the County owns and operates four wells at the Lahaina Wastewater Reclamation Facility (“LWRF”), the principal municipal wastewater treatment plant for West Maui.

When the LWRF first opened, the Clean Water Act prohibited the facility from discharging treated effluent directly to the Pacific Ocean. So the facility built four “backup” wells where effluent is stored and discharged into the island’s groundwater. The groundwater, however, flows to the Pacific Ocean.

Due to increased wastewater volume, the Hawaii Wildlife Fund accused the County of discharging directly to the Pacific Ocean, requiring a NPDES permit and regulation under the Clean Water Act. The County disagreed.

The case went to court and the ruling was in favor of the Hawaii Wildlife Fund, stating that the LWRF’s discharge does fall under the Clean Water Act.

Two months after the Ninth Circuit decision, a court case in the Fourth Circuit agreed that discharges via groundwater are subject to the CWA. On April 12, 2018, the Fourth Circuit ruled in Upstate Forever v. Kinder Morgan Energy Partners that “discharges to hydrologically-connected groundwater can give rise to liability under the CWA.”

These decisions, however, are at odds with EPA’s most recent statement.

The case Hawaii Wildlife Fund v. County of Maui is currently being considered by the U.S. Supreme Court. Once the Supreme Court has issued its decision, the Agency may take further action. So stay tuned…

NPDES Specifics

Currently, the CWA prohibits anybody from discharging pollutants through a point source into a Water of the United States unless they have an NPDES permit. The permit contains limits on what can be discharged; monitoring and reporting requirements; and other provisions to ensure that the discharge does not hurt water quality or people’s health.

A company requires an NPDES permit if it discharges from a point source into the Waters of the United States.

A “water of the U.S.” refers to navigable waters, tributaries to navigable waters, interstate waters, the oceans out to 200 miles, and intrastate waters which are used by interstate travelers for recreation or other purposes, as a source of fish or shellfish sold in interstate commerce, or for industrial purposes by industries engaged in interstate commerce.

The CWA broadly defines a pollutant as any type of industrial, municipal, and agricultural waste discharged into water, i.e. dredged soil, solid waste, incinerator residue, sewage, and garbage.

If a company discharges pollutants into a municipal sanitary sewer system, chances are that the company will not need an NPDES permit. However, it is best to ask individual municipalities.

According to this newest interpretation, a company discharging directly into the groundwater does not require a NPDES permit. However, individual state regulations may apply.

NPDES permits last five years and are issued by EPA-approved states or by EPA Regions in states without such approval. See for more information.

Finally, you can better ensure compliance with the CWA and other water regulations, and manage permits more effectively through water management software offered by Enablon. Check out the application webpage for more details.

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Laurie Toupin