ALSO SEE: Oklahoma Earthquake Officially
Largest in State's History

Only a Fraction of Oklahoma's Disposal Wells Shut Down After Quake

By The Washington Post

06 September 16

he 37 wastewater disposal wells to be shut down in north-central Oklahoma, where a 5.6 magnitude earthquake struck this weekend, are just a fraction of the state’s total number.

There are about 4,200 total wells across the state and about 700 in a 15,000-square-mile “Area of Interest” created by the commission to address earthquakes in the area that includes the epicenter of Saturday’s temblor near Pawnee. But the Oklahoma Corporation Commission said that at any one time, there are about 3,200 active disposal wells.

The earthquake tied a November 2011 quake as the strongest in recorded state history and was felt as far away as Nebraska, but no major damage was reported.

An increase in magnitude 3.0 or greater earthquakes in Oklahoma has been linked to underground disposal of wastewater from oil and natural-gas production, and since 2013, the commission has asked wastewater-well owners to reduce disposal volumes in parts of the state where the temblors have been most frequent.

Gov. Mary Fallin (R) declared a state of emergency in Pawnee County because of the earthquake. State and local emergency management officials and officials from the U.S. Geological Survey assessed the damage Sunday.

“We’re just trying to determine just how widespread” the damage is, Pawnee County Emergency Management Director Mark Randell said. He described it as minor to moderate, with some collapsed chimneys and fallen sandstone facing off buildings; no buildings collapsed.

None of the utilities, pipelines or fuel infrastructure in the area had major damage, either, the commission said. The Oklahoma Department of Transportation inspected 180 state bridges within a 30-mile radius of the epicenter and reported minor cosmetic damage to two structures, but all are open and safe for travel.