The rapid expansion of shale drilling in recent years has brought with it an increase in the wastewater that is generated during the fracking process. One fracking well can produce over one million gallons of wastewater in a year. In March of 2011, the EPA released “Natural Gas Drilling in the Marcellus Shale: NPDES Program Frequently Asked Questions,” which explained that because natural gas drilling in the Marcellus Shale can result in direct and indirect discharges into waters of the United States, those operations are subject to requirements under the Clean Water Act. However, aside from the Clean Water Act requirements, shale drilling was largely exempt from EPA regulation. In response to public concern about the effect of fracking wastewater on human health and the environment, the EPA released a statement in October of 2011 announcing that by 2014, it would propose standards that shale gas wastewater would have to meet before going to a treatment facility. A draft of the rules was recently leaked, and shows the EPA’s proposed guidelines on water quality limits, removal of pollutants, and permits for treatment of discharged shale wastewater.
The leaked draft, titled “National Pollutant Discharge Elimination System Permitting and Pretreatment for Shale Gas Extraction Wastewaters: Frequently Asked Questions,” details the EPA’s proposed pretreatment standards for shale wastewater. The document notes that the EPA has identified potential pollutants in shale wastewater, including chlorides, bromide, metals, and organics, based on a limited set of data from the Marcellus shale. The document lists about twenty substances in shale wastewater that the EPA signals might have an impact on water quality and permitting for wastewater. Depending on the contaminants found in the wastewater, drilling companies may be subject to additional permitting or other controls to ensure that pollutants are removed before reaching a water source.
The document also offers guidance about the management and pretreatment of shale wastewater. It indicates a potential reduced need to discharge shale wastewater to centralized waste treatment (CWT) and publicly owned treatment works (POTWs) due to an increase in wastewater recycling and underground disposal wells. The leaked draft provides POTWs with examples of pollutant parameters to determine whether POTWs should establish local limits or accept shale wastewater. The EPA also identified various levels of dissolved solids that might impact POTWs, and may provide guidance on those, as well.
The EPA’s finalized rules for disposal of shale wastewater are set to come out later this year.