The Sierra Club has filed suit against three oil and gas companies operating in Oklahoma, alleging that the companies’ wastewater injection practices were behind the recent uptick in earthquake activity in the state. The petition, which was filed in the U.S. District Court for the Western District of Oklahoma on February 16, seeks relief under the federal Resource Conservation and Recovery Act. It named Chesapeake Operating LLC, Devon Energy Production Co. LP, and New Dominion, LLC as defendants, and asked that the companies reduce the amount of production waste being injected into the ground to “levels that seismologists believe will not cause or contribute to increased earthquake frequency and severity.”