Environmentalists are threatening to sue four Oklahoma oil/gas operators, accusing them of causing earthquakes by injecting drilling waste into underground disposal wells.

Oklahoma seismic activity has been on the upswing in the last two years, and drilling waste injection wells have been blamed by some (see Shale Daily, Oct. 22; Oct. 19). Now, environmental groups Public Justice and the Sierra Club have said they plan to sue operators. The companies are Sandridge Exploration and Production LLC, New Dominion LLC, Chesapeake Operating LLC, and Devon Energy Production Co. LP.

In a “notice of intent to sue for violations of the Resource Conservation and Recovery Act,” the group said operators should “immediately and substantially” cut the volume of waste they inject into the ground. Additionally, they should reinforce structures that are most vulnerable to large-magnitude earthquakes, and establish an independent monitoring and prediction center to forecast the amount of waste that can be safely injected while tracking seismic activity to confirm and modify those predictions.

“Oklahoma is literally being shaken to its core by the operations of these oil and gas companies,” said Paul Bland, executive director of Public Justice. “If the energy companies do not voluntarily take action to stop it, we will take them to court.”

The companies have 90 days to respond.