Wastewater Management and Induced Seismicity

Keith B. Hall, Paul M. Herbert Law Center, Louisiana State University, Baton Rouge, Louisiana 70803: keith.hall@law.lsu.edu

Oil and gas activities in the United States generate large volumes of wastewater—about 890 billion gallons of wastewater in 2012.  Some of this water is wastewater from hydraulic fracturing operations (sometimes called “flowback”), but a much larger portion is water that is naturally found in subsurface formations that also contain oil or gas.  Such water flows to the surface with the hydrocarbons that are produced by an oil or gas well.  But all of this wastewater—whether flowback or formation water—must be managed.

In the United States, there are several different methods used to manage oil and gas wastewater (such water is sometimes called “produced water” or “brine” or “saltwater”).  Throughout the country, injection disposal is one of the most common methods of managing oil and gas wastewater, and in Louisiana and in some other states, the vast majority of such water is sent to injection disposal wells.  For years, injection disposal has been considered an economical and environmentally safe method of disposal.  But for several decades scientists have known that, in certain circumstances, the injection of fluids into the subsurface can induce seismic activity, and in recent years some states have seen a dramatic increase in seismic activity—an increase that many scientists attribute to the injection disposal of wastewater generated by oil and gas activities.

Several states have responded by promulgating new regulations relating to injection disposal operations or by adopting a policy that the agency will expressly consider the risk of induced seismicity when evaluating applications for permits for new injection disposal wells.  Further, numerous plaintiffs have brought suit, alleging that they have incurred damages that were caused by earthquakes induced by injection disposal operations.  This paper examines recent trends in regulations and litigation, and considers what they mean for the management of wastewater from oil and gas activities.