EPA Asserts Position On Clean Water Act, Groundwater Discharge Oversight

According to a recent interpretation of the Clean Water Act, the U.S. EPA won’t regulate pollution that occurs in surface water if it passes through groundwater first.

While the Clean Water Act unambiguously requires the EPA to oversee pollution to surface waters, and requires permits for operations that discharge to them, the agency released a statement this month clarifying that the same is not true for pollution that winds up in surface water if it travels through groundwater first.

“The Environmental Protect Agency (‘EPA’) is issuing an Interpretative Statement addressing whether the Clean Water Act (‘the CWA’ or ‘the Act’) National Pollutant Discharge Elimination System (‘NPDES’) permit program applies to release of a pollutant from a point source to groundwater,” according to the statement. “The Agency concludes that the CWA is best read as excluding all releases of pollutants from a point source to groundwater from NPDES program coverage, regardless of a hydrologic connection between the groundwater and jurisdictional surface water.”

This interpretation, which may conflict with an interpretation of the rule that the EPA and the U.S. Department of Justice made in 2016, could have major implications for operations that discharge wastewater and, later on in the water system, for drinking water treatment operations.

“That could affect regulation of pollution from a variety of sources, including seepage from coal ash and manure management ponds, sewage collection systems, septic system discharges, and accidental spills and releases,” according to E&E News.

It remains to be seen exactly how the EPA will enforce the CWA under its latest interpretation, but environmental groups are already worried that this will grant new leniency to operations that discharge into groundwater and ultimately pollute surface water.

“Environmental groups acknowledge that the landmark environmental law does not regulate groundwater itself but say that’s not the same as allowing pollution to reach surface water if it travels through groundwater,” per E&E News. “They have argued in favor of regulating surface water pollution when it can be directly traced back to a point source, regardless of whether it first traveled through groundwater.”

Ultimately, the guidance will not be applied until after the U.S. Supreme Court hears a case regarding the 2016 interpretation of the Clean Water Act — at least in the jurisdictions that ruling affects. Depending on how the Supreme Court rules, EPA’s interpretation may move forward or be adjusted once again.

“The U.S. Supreme Court said earlier this year that it will hear a case this fall that involves pollution of groundwater that is hydrologically connected to regulated surface waters,” according to Circle of Blue. “Federal circuit courts have issued contradictory opinions on the question. Due to those opinions, the agency will wait until the Supreme Court issues a ruling before it applies the guidance to states that are under the Fourth and Ninth circuit court jurisdiction.”

To read more about the rules that apply to wastewater discharge, visit Water Online’s Wastewater Regulations And Legislation Solutions Center.