Environmental Protection Agency has finalized its proposed “zero discharge” rule for the oil and gas industry, with a Federal Register Notice published on Tuesday, June 28, 2016 [81 Fed. Reg. 41845]. The rule aims to protect rivers and drinking water supplies from direct discharges by municipal sewage plants of wastewater resulting from unconventional oil and gas (UOG) extraction, also known as hydraulic fracturing of shale or tight geologic formations.  EPA’s update to the Effluent Guidelines under the Clean Water Act prohibits oil and gas companies from sending their UOG extraction wastewater to publicly owned treatment works (POTWs) for disposal. more

According to EPA, the rule is needed because “most POTWs are designed to treat pollutants found in municipally-generated, not industrial, wastewater.  They typically provide at least secondary level treatment and, thus, are designed to remove suspended solids and organic material using biological treatment.  Wastewater from UOG extraction can contain high concentrations of dissolved solids (or salts), as well as pollutants such as radioactive elements, metals, chlorides, sulfates, and other dissolved inorganic constituents that POTWs are not designed to remove.  Because they are not typical of the POTW influent wastewater, some UOG extraction wastewater constituents can be discharged, untreated, from the PTOW to the receiving water; can disrupt the operation of the POTW (e.g., by inhibiting biological treatment); can accumulate in biosolids (sewage sludge), limiting their use; and can facilitate the formation of harmful DBPs [disinfection by-products].”

EPA indicated that it was adopting pretreatment standards based on current industry practices of disposal by underground injection, reuse/recycling or management by centralized waste treatment facilities, rather than use of POTWs.  Some commenters had urged EPA to provide some non-zero pretreatment standard as an “escape-valve” for the future in the event that UIC disposal capacity is exhausted, or if other technologies are developed to allow for cost-effective pretreatment.  EPA rejected this suggestion for several reasons.  First, because there is zero direct discharge authorized for UOG extraction wastewater, EPA decided to create a comparable zero discharge requirement for indirect discharge.  This is consistent with the agency’s practice of ensuring that direct and indirect discharges provide for comparable pollutant removal before discharge to waters of the United States.  Second, EPA noted that industry is currently meeting the zero discharge requirement and that anything else would be less stringent than current practices and might increase discharge of pollutants to POTWs.  Third, EPA disagreed that an “escape valve” option was necessary. According to EPA, “UIC disposal capacity is currently widely available, and EPA does not have data to suggest that this capacity will be limited in the future.”  Finally, EPA noted that while technology exists to treat dissolved pollutants to allow disposal of UOG extraction wastewater in POTWs, that technology is too costly.

The final rule applies only to onshore extraction from unconventional oil and gas extraction resources.  It does not does not include pretreatment standards for wastewater pollutants associated with conventional oil and gas extraction facilities or coalbed methane extraction facilities.  EPA notes it is reserving such standards for a future rulemaking, if appropriate.

The rule becomes effective August 29, 2016.