OKLAHOMA CITY, Feb. 17 (UPI) -- Environmental advocacy group Sierra Club said it filed a lawsuit against energy companies involved in Oklahoma shale in part because of the rise of earthquakes.
The U.S. Geological Survey reported five tremors of magnitude-3.1 or less early Wednesday. That follows the steady string of minor quakes that followed a magnitude-5.1 earthquake recorded Saturday near Fairview, about 100 miles north of Oklahoma City.
The USGS reported last year the increase in seismic activity in Oklahoma since 2009 may be in part related to activity associated with oil production. The agency said the disposal by the energy industry of wastewater in deep underground wells is potentially leading to more earthquakes.
The Sierra Club and Public Justice filed a federal lawsuit against energy companies New Dominion, Chesapeake Operating and Devon Energy Production Co., calling on them to cut back on the amount of waste injected underground.
"The dangers associated with fracking and its related processes has never been more clear than it is here in Oklahoma," Johnson Bridgwater, director of Sierra Club's Oklahoma chapter, said in an emailed statement. "It is our hope that these three companies will recognize the immediate danger they are putting communities in, and put our health and our environment ahead of its profits."
Oklahoma's governor, Mary Fallin, in January authorized the use of $1.4 million from state emergency funds to help drive earthquake research at state agencies. The state, one of the top 5 oil producers in the country, reported 907 earthquakes of magnitutde-3 or greater last year, up 54 percent from 2014.
The targets of the suit issued no public comment on the Sierra Club's statement on the perceived dangers tied to hydraulic fracturing, an industry practice known also as fracking. Apart from a reduction in wastewater injection, the suit calls on the companies to reinforce structures that may be vulnerable to seismic activity.
"It also asks the court to require the establishment of an independent earthquake monitoring and prediction center," the advocacy group said.