Are Disposal Wells Causing Seismic Activity? An Overview of the Current Debate

Are Disposal Wells Causing Seismic Activity? An Overview of the Current Debate

The heated debate has centered on whether disposal wells or fracking are causing seismic activity. The arguments started to surface due to areas with heavy oil and gas activity, specifically Oklahoma and Texas, having a rise in earthquake activity. Recently, one earthquake in Oklahoma caused damage to over 200 buildings.[1] More overwhelmingly, California, a state sitting on top of the San Andreas fault, where you would expect much more tectonic plate activity, is now behind Oklahoma in the number of earthquakes per year.[2] Although some activity along fault lines is expected, more action around tectonic plates is expected.[3] As of 2014, Oklahoma was the most “seismically active state in the Lower 48 and recorded three times as many quakes as California.”[4] From 2000 to 2015, Oklahoma has transformed from experiencing two earthquakes a year into experiencing about three a day.[5]

Drilling and Fracking

Years ago, the argument was that oil and gas work generally was causing seismic activity. Some still attribute all oil and gas work that involves drilling and fracking to be the cause of earthquakes, but this is not a widely accepted opinion. Fracking involves the process of shooting liquid into the ground to open or widen fissures to extract oil. The view that fracking directly causes seismic activity has largely been dismissed by experts because, generally, fracking does not involve injecting liquid into the earth at the depth necessary to induce earthquakes; it is simply too shallow.[6] According to Ryan Sitton, a Texas Railroad Commission member and a mechanical engineer, “It is widely known in the scientific community, including the EPA and US Geological Survey, that drilling and fracking do not typically produce the pressure necessary to cause a felt seismic event.”[7]

 However, there may be more support that fracking indirectly causes earthquakes, meaning that disposal wells, which are created due to the process of fracking, may be linked to seismic activity. Sitton mentioned that “[w]e cannot definitively say that there is or is not a direct causal relationship between disposal wells and earthquakes in Texas. It is absolutely possible, and that is why we at the Railroad Commission are studying it and have taken concrete steps to strengthen our disposal well rules.”[8]

Disposal of Wastewater

 A majority of seismologists believe that wastewater disposal is responsible for the “vast majority of induced earthquakes.”[9] This is the current prevailing view because of studies done in Oklahoma and Texas near sites of disposal wells. However, it is important to note that most injection wells are not associated with earthquakes.[10] The likelihood of an earthquake is related to: “the injection rate and total volume injected; the presence of faults that are large enough to produce felt earthquakes; stresses that are large enough to produce earthquakes; and the presence of pathways for the fluid pressure to travel from the injection point to faults.”[11] Additionally, earthquakes can be induced up to 10 miles or more away from the injection site.[12]

Although not every disposal well will cause an earthquake, a combination of the above listed factors increases the chances and the severity of an earthquake happening. For instance, one of the key issues with wastewater injection sites in Oklahoma is the combination of the forced pressures along the fault lines. While wells do not necessarily require fault lines to cause earthquakes, this significantly increases the likeliness of an earthquake occurring.[13]

Some have also argued simply that “Oklahoma is located on a fault line, and seismic activity is believed to have been going on for thousand of years. . . . The practice of underground disposal has been used by the industry for 70 years, yet the uptick in seismic activity has only occurred in the past few years.”[14] Therefore, some believe that drilling and anything oil and gas related has not caused the increase in seismic activities.

What do the Lawyers Have to Say?

 No matter your viewpoint on what is causing the seismic activity in Oklahoma or Texas, earthquake litigation has spiked following earthquakes in Oklahoma.[15] At the core of these debates is “whether and how the volume and pressure of injected fluids, particularly in areas with geological faults, may be linked to earthquakes that inflict specific damage above the ground.”[16] Although there may be a rise in suits, defense attorneys are not as concerned as you may think.[17] Plaintiffs will most likely have a tough time proving damages inflicted by a particular company because “scientific studies suggest only a ‘weak’ connection between waste water disposal wells and . . . induced earthquakes.”[18] The most “threatening litigation” of 2017, brought by the Sierra Club against four oil and gas producers for violating the Resource Conservation and Recovery Act while operating disposal wells that have been linked to quakes,[19] was dismissed.[20] This dealt a major blow to banning wastewater injection in Oklahoma. Additionally, it has put more pressure on seismologists to establish the link between disposal wells and seismic activity. The courts have simply believed the proof is not strong enough. However, there is still plenty of time to see how litigation from earthquakes in 2015 and 2016 will unfold.

What is the Current Solution?
Indubitably, the issue of the use of water in the oil and gas industry is growing. Not only is water being depleted from the water table, but the water remaining after hydraulic fracking generally needs to be discarded using disposal wells. In order to frack, companies need millions of gallons of water. To get rid of the wastewater after, many companies have injected the water back deep into the earth using disposal wells.[21] Due to the link of disposal well injections and earthquakes, some states have imposed restrictions on the use of these disposal wells.[22] Some states, like Oklahoma, have seen success. Oklahoma was experiencing an “unusually” large number of earthquakes, but since state authorities have imposed restrictions on disposal wells, the number of earthquakes has tapered off.[23] This has led to the current solution—an increase in recycling plants geared towards wastewater. The movement towards reuse through recycling facilities is growing in popularity. However, it will remain to be seen how effective this reuse solution is, as the cost of building and operating a recycling facility is expensive.[24] A solution revolving around the preservation of water must be found—either by finding ways to withdraw water from the fracking process altogether or by making it more efficient to reuse the frack water.

[1] Joe Wertz, Exploring the Link Between Earthquakes and Oil and Gas Disposal Wells. State Impact.

[2] Max Galka, Setting the Record Straight on Fracking and Earthquakes. Metrocosm (Mar. 7, 2016),

[3] Tectonic Setting. USGS.

[4] Wertz, supra note 1.

[5] Galka, supra note 2.

[6] Wertz, supra note 1.

[7] Ryan Sitton, Disposal Wells, Not Drilling, Studied for Earthquake Link, Star Telegram Blog (Aug. 24, 2016),

[8] Id.

[9] Galka, supra note 2.


[11] Induced Earthquakes. USGS,

[12] Id.

[13] Wertz, supra note 1.

[14] Galka, supra note 2.

[15] Daniel M. McClure, Barclay Richard Nicholson, Lauren Brogdon & Emery Gullickson Richards, Earthquake Litigation Spikes Following Recent Oklahoma Quakes.

[16] Steven M. Sellers, Earthquakes, Fracking, Disposal Wells … and Litigation, Bloomberg Law (Apr. 29, 2016).

[17] Id.

[18] Id.

[19] Ellen M. Gilmer, Oil and Gas Federal Challenges, Local Control Dominate Year in Litigation, E&E (Dec. 22, 2015),

[20] Joe Wertz, Alternative to Earthquake-Linked Wastewater Disposal Stirs up Opportunity for Oklahoma’s Oil Industry, State Impact (Aug. 3, 2017),

[21] Id.

[22] Id.

[23] Id.

[24] Id.