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The earthquake was felt across 7 states

No injuries have been reported

CNN —  

The Oklahoma Corporation Commission is telling operators to shut down 35 disposal wells that may have played a role in a 5.6-magnitude earthquake that shook at least six states Saturday, Gov. Mary Fallin said.

The disposal wells, which are linked to fracking and other industries that need to dispose of toxic waste water by injecting it deep into the earth, have recently drawn concern that they may actually induce earthquakes.

“This is a mandatory directive,” Fallin said.

The commission, which regulates fuel, oil, gas, public utilities and transportation industries, is investigating to determine the epicenter of the quake that hit Pawnee, said commission spokesman Matt Skinner.

The Environmental Protection Agency is also investigating, Fallin said.

Skinner says earthquakes in Oklahoma are generally not directly caused by fracking, but rather by pressure from the disposal wells, which are used by the industry to get rid of the toxic waste water that comes out of the earth along with oil and gas.

“The disposal wells dispose into the state’s deepest formation, the Arbuckle formation, which is right above what we call the basement,” Skinner said. The basement is above where the critical faults lie that shift and make earthquakes.”

Those disposal wells within five miles of the 10-mile section of the fault in question are to be shut down within seven days, and all the other wells must be shut down within 10 days, Fallin said.

Controversial disposal method