Are Injection Wells Causing Earthquakes?
By Leslie Vaughn – 2L
A rise in lawsuits related to earthquakes allegedly causing by hydraulic fracturing or “fracking” has sparked a debate about the substantive scientific basis for such claims, as well as the ability to prove legally compensable damages. While several studies within across the U.S. claim to have proof of substantial increases in earthquakes caused by fracking activities, counsel for many of the companies hit with lawsuits are outspoken in their belief that the science to support such claims simply is not developed enough to stand up in the courts. 1
In many of these cases, there is no previous data to show a lack of naturally occurring quakes prior to the drilling activities. Additionally, the sources of natural earthquakes are often difficult to pinpoint, creating a high burden for plaintiffs to prove that the quakes in question were in fact caused only by the fracking activities and not by natural forces.
It is also important to distinguish between the actual hydraulic fracturing process (where water, sand, and chemicals are injected under high pressure into a well to crack the rock and release natural gas) and the injection of drilling wastewater into disposal wells. Fracking itself has only been known to rarely cause earthquakes, while the pumping of wastewater deep into disposal wells is now believed to cause slips in existing faults, creating earthquakes. 2
A study by University of Texas and Southern Methodist University Geophysicists has found that most of the earthquakes in the Barnett Shale region of North Texas occur within a few miles of one or more injection wells used to dispose of wastes from fracking and other petroleum production processes. 3 Using data collected by the EarthScope USArray Program, researchers were able to reliably locate eleven earthquakes between November 9 2008 and January 2 2009, all within .5 km of a deep saltwater disposal (“SWD”) well where injections began on September 12, 2008. 4 Most interestingly, the team detected no earthquakes in 2008 prior to October 29, and approximately seven weeks after injections began at the SWD well, the USGS National Earthquake Information Center (“NEIC”) located nine earthquakes with magnitudes between 2.5 and 3.0. 5 The researchers from SMU and UT believe the nine NEIC quakes also originated from the same DFW focus as their eleven EarthScope quakes. 6
While the fluid injection volumes for the SWD well in question were no higher than in other locations where no earthquakes were reported, the state tectonic map shows a fault that intersects the Dallas-Tarrant county line approximately at the DFW focus. 7 Fluid injections into faulted areas have been known to cause earthquakes, most notably in 2012 in Youngstown, Ohio where a series of quakes culminated in a 4.0 magnitude event on New Years Eve. 8 A paper published by the Colorado Geological Survey lists four series of earthquakes currently believed to have been caused by water injection including the events in Youngstown, Arkansas, Oklahoma, and the Raton Basin of Colorado and New Mexico. 9
Despite what appears to be substantial scientific evidence linking wastewater injections to earthquakes, researchers are still hesitant to give any definitive significance to their findings. While confident in their data, many still use qualifying words like “probable” 10 or “plausible” 11 when naming wastewater injections as the cause for the quakes. Additionally, there does seem to be a consensus that regardless of the cause, the actual damage from these quakes is minimal, if at all. Without substantial injuries to person or property, it will be difficult for plaintiffs to claim damages in court. While some plaintiffs have attempted to pursue a claim for loss of market value of their homes, this is unlikely to prevail without proof of continuing and persistent quakes that will permanently decrease the value of their land. 12
While individual plaintiffs may be unable to succeed in claims against fracking companies, the increased publicity from the lawsuits has certainly attracted the attention of legislatures and regulators. In July, 2012, Ohio Governor John Kasich signed and order that allows for required seismic testing before well drilling and sets maximum injection pressure standards for approved wells. 13 However, concern about the enactment of regulation without scientific consensus may be holding some state legislatures back. Despite hearing testimony from experts regarding the need for state enforced safeguards, the Texas Railroad Commission appears to have adopted a “wait and see” approach to the issue. 14 While this passive approach may seem prudent, as past quakes have remained below the 4.0 magnitude generally required to do any substantial damage, new evidence suggests that the longer a disposal well is injected with fluid, the greater the likelihood of a stronger quake. 15 This means that many injection wells across Texas and the country could become more and more prone to larger quakes the longer injection activity continues. It seems unlikely, however, that state legislators or private companies will seriously consider alternative disposal methods until the science or the consequences become more concrete.
- Sean McLernon, Fracking Earthquake Claims Bank On Uncertain Science, Law360 New York (August 26, 2013, 6:15 PM ET), http://0-www.law360.com.tallons.law.utexas.edu/articles/467693/fracking-earthquake-claims-bank-on-uncertain-science. ↩
- Id ↩
- Study Finds Correlation Between Injection Wells and Small Earthquakes, The University of Texas News (August 6, 2012), http://www.utexas.edu/news/2012/08/06/correlation-injection-wells-small-earthquakes/. ↩
- Frohlich, C., Potter, E., Hayward, C., and Stump, B., Dallas-Fort Worth earthquakes coincident with activity associated with natural gas production, The Leading Edge, Volume 29, Issue 3 (March 2010),http://smu.edu/newsinfo/pdf-files/earthquake-study-10march2010.pdf. ↩
- Id ↩
- Id ↩
- Id ↩
- Mark Fischetti, Ohio Earthquake Likely Caused by Fracking Wastewater, Scientific American (January 4, 2012), http://www.scientificamerican.com/article.cfm?id=ohio-earthquake-likely-caused-by-fracking. ↩
- Earthquakes Triggered by Humans in Colorado—a background paper by the Colorado Geological Survey, Colorado Geological Survey, http://geosurvey.state.co.us/hazards/Earthquakes/Documents/Earthquakes%20Triggered.pdf.↩
- Id ↩
- Frohlich, supra note 7 ↩
- McLernon, supra note 1 ↩
- Mclernon, supra note 1 ↩
- How Oil and Gas Disposal Wells Can Cause Earthquakes, StateImpact, http://stateimpact.npr.org/texas/tag/earthquake/. ↩
- Id ↩