Oklahoma earthquakes prompt changes in well operations

Daniel C. Houston
Associated Press

Oklahoma City — Oklahoma oil-and-gas regulators on Tuesday issued their most far-reaching directive yet in response to a surge in earthquakes by asking the operators of nearly 250 injection wells to reduce the amount of wastewater they inject underground by 40 percent.

The Oklahoma Corporation Commission wants operators to reduce injections by more than 500,000 barrels of wastewater daily in an area that covers more than 5,200 square miles of northwest Oklahoma.

A 5.1-magnitude quake hit the area Saturday: it was the third-strongest in state history. People reported feeling Saturday’s quake in as many as 13 other states, including in Georgia, 900 miles away.

As the Corporation Commission was preparing to announce its move, the Sierra Club filed a lawsuit asking that three major Oklahoma energy producers reduce wastewater volume.

The number of earthquakes with a magnitude 3.0 or greater has skyrocketed in Oklahoma, from a few dozen in 2012 to more than 900 last year. Recent peer-reviewed studies suggest injecting high volumes of wastewater could aggravate natural faults. In Oklahoma’s six most earthquake-prone counties, the volume of wastewater disposal increased more than threefold from 2012 to 2014.

Most operators comply with commission directives, though one — SandRidge Energy Inc. — initially refused to comply before reaching an agreement with the agency last month. Oklahoma House Speaker Jeff Hickman, whose home is 20 miles from the epicenter of Saturday’s quake, is pushing a bill to make clear the Corporation Commission has the power to order wells to shut down or reduce volume.

“We will remove any doubt at all that the commission has complete authority in these emergency situations, without so much as a notice or hearing, to take whatever action they believe is necessary in these emergency situations,” said Hickman, a Fairview Republican whose bill is set for review in a House committee Wednesday.

In its lawsuit, the Sierra Club wants to see immediate, substantial reductions to their wastewater-injection levels. The lawsuit claims wastewater disposal from hydraulic fracturing operations at Chesapeake Operating, Devon Energy Production Co. and New Dominion is contributing to the increased number of earthquakes.

Devon spokesman John Porretto said it would be inappropriate to discuss the litigation. The other companies didn’t immediately reply Tuesday to requests for comment.