For a year, Faulkner County (roughly 741,000 acres) in Arkansas was shaken by thousands of mini-earthquakes caused by landfills deep underground composed of wastewater (also known as processed water) used in the shale gas extraction process. Instead of treating the processed water which returns to the surface from wells where hydraulic fracturing is practiced, the gas companies chose to dispose of the water in injection wells (which is a type of underground landfill where the water is violently forced hundreds of yards into the ground through hydraulic fracturing). The most violent of all these earthquakes hit on February 27, with a 4.7 magnitude.
Injection wells are used to store waste deep below the surface, such as disposing wastewater from hydraulic fracturing.
The Arkansas Geological Survey and the Center of Seismographic Information and Research at the University of Memphis conducted a study, and established a link between the mini-earthquakes and certain fracking activities operated by Chesapeake Energy and Clarita Operating LLC. Although no official link has been established, the authorities have noticed that seismic activity significantly decreased after two shale gas operations were closed. The injection wells’ operations have been stopped since then, and are awaiting a July 26 hearing before the Oil and Gas Commission.
In May, a couple in Faulkner County filed a lawsuit against the companies responsible for disposing wastewater near their place of residence. The couple was convinced that there was a link between the hydraulic fracturing and the hundreds of mini-earthquakes that rocked their property. Even if such a lawsuit was successful, it would only affect the area between Conway and Greets Ferry Lake (where the earthquakes previously occurred). The gas companies would then just have to take their fracking a little farther down the road.
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