On Monday, November 2, the Sierra Club issued a Notice of Intent to Sue (“Notice”) four oil companies, alleging ongoing violations of the Resource Conservation and Recovery Act (“RCRA”).  Specifically, the Notice states that the injection and disposal of hydraulic fracturing waste fluids into the ground is a “past and present handling and disposal of Production Wastes in a manner that may present an imminent and substantial endangerment to health and the environment,” in violation of RCRA.  The Notice claims that fluid injection by oil companies, Sandridge Exploration and Production, New Dominion, Devon Energy Production Co. and Chesapeake Operating, is contributing to increased earthquakes in Oklahoma and southern Kansas.

This Notice follows a recent publication by the U.S. Geological Survey (“USGS”).  On October 20, the USGS released a reportA Century of Induced Earthquakes in Oklahoma?, that reviews the increased rate of seismicity in the central and eastern U.S. since 2009.  The report attempts to link industrial activity to the incidence of large earthquakes in the region.  As the Sierra Club Notice points out, the report states that injection of wastewater in deep disposal wells “potentially” induces earthquakes.  Additionally, a research letter published in October 2015 examined the two Cushing, Oklahoma earthquakes that occurred in October 2014, stating that a study of earthquake hazards and “its relationship to wastewater injection is important in order to understand potential damage to critical infrastructure in the region.”

Should this be a cause for public concern?  Probably not.  Of the 170,000 Class IIUnderground Injection Wells, only 40,000 are waste fluid disposal wells for oil and gas operations.  Further, the USGS reports that “[o]nly a small fraction of these disposal wells have induced earthquakes that are large enough to be of concern to the public.”