A 5.6-magnitude earthquake shook communities from Illinois to southwest Texas Saturday morning, raising new concerns about underground disposal of fracking waste from oil and gas fields in Oklahoma.
The quake was centred in the north-central part of the state, “on the fringe of an area where regulators had stepped in to limit wastewater disposal,” AP reports. It tied the record for the most intense earthquake the region had ever seen, set in November 2011.
“The Oklahoma Corporation Commission, which since 2013 has asked wastewater-well owners to reduce disposal volumes in parts of the state, is requiring 37 wells in a 514 square-mile area around the epicenter of the earthquake to shut down within seven to 10 days because of previous connections between the injection of wastewater and earthquakes,” AP reports.
“We’re trying to do this as quickly as possible, but we have to follow the recommendations of the seismologists, who tell us everything going off at once can cause [another quake],” explained spokesperson Matt Skinner.
People felt Saturday’s shocks in Kansas City and St. Louis, Missouri; Chicago; Gilbert, Arizona; Fayetteville and Little Rock, Arkansas; Des Moines, Iowa; Memphis, Tennessee; and Big Lake, Texas, AP notes.
