At the American Geophysical Union meeting in San Francisco last week, scientists presented the latest evidence tying the disposal of wastewater from shale gas hydrofracking to increased earthquakes.
Some U.S. states, including Oklahoma, Texas, and Colorado, have experienced a significant rise in seismic activity over the last few years, coinciding with a boom in fracking—a process that forces gas from hard-to-reach underground deposits by injecting water and chemicals into shale rock. Fracking produces huge quantities of wastewater that is typically disposed of in deep wells. But the degree to which the disposal of wastewater from fracking operations has caused the unusual seismic activity is still up for debate among scientists.
The question matters because most states don’t consider earthquake risk when allowing gas drilling companies to dispose of large volumes of chemical-laden drilling water.
Manmade earthquakes, triggered by underground injections, have been known about for a long time, at least since the 1960s, when an Army waste disposal well triggered an earthquake that caused major damage in Denver.
Overall, however, experts seem to believe the “seismic hazard” in many shale gas states is growing: “The future probably holds a lot more in induced earthquakes as the gas boom expands,” says USGS Earthquake Science Center researcher Art McGarr.
Read more at Studies Link Earthquakes to Wastewater from Fracking