Eight small earthquakes in central West Virginia have led state regulators to consider seismic monitoring near a disposal well for natural gas-drilling fluids. Oklahoma-based Chesapeake Energy "has injected more than 10.6 million gallons of brine and hydraulic fracturing fluid into the well since March 2009," The Associated Press reports. "Some geologists suspect high pressure and wastewater have lubricated old fault lines, allowing them to slip and trigger small earthquakes. Chesapeake isn't so sure, but it has agreed to reduce the volume of fluid it's injecting."
Gene Smith, compliance manager for the West Virginia Department of Environmental Protection, told AP no seismic events have been reported at 70 similar disposal wells around West Virginia, but the state will investigate. "We're looking at the mechanics of the well, the geology of the area and the events that have been happening in the area, to see, from a scientific level, if what's taking place could cause earthquakes," Smith told AP. Since April 4, eight earthquakes between 2.2 and 3.4 on the Richter Scale have hit Braxton County, though no damage was reported.
Marshall University geology professor Ronald Martino told AP it was "quite possible" the quakes are linked to the high-pressure injection of fracking fluids. Chesapeake spokeswoman Maribeth Anderson countered "natural seismicity has long been observed in this part of Appalachia," and seismic activity often occurs in clusters. A study released in March University of Texas and Southern Methodist University pointed to similar disposal wells as a likely cause of several small earthquakes near Grand Prairie and Irving. (Read more)
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