Oklahoma imposes rules over disposal wells; link to rise in earthquakes
The Oklahoma Corporation Commission has told energy companies to reduce the amount of wastewater they inject below ground by 38%, after scientific studies said the increasing number of earthquakes are caused by a corresponding increase in the underground disposal of salty wastewater.  Oklahomans have been advised that until the problem is solved, they should buy private earthquake insurance to protect their homes. Standard & Poor's stated yesterday that increased and stronger earthquakes, and the possible link with oil and gas drilling activities, would have "far reaching economic implications" for home owners, mortgage lenders and insurance companies.
Oklahoma regulators have told energy companies to sharply reduce underground wastewater disposal across an earthquake-prone stretch of the state, a move that ratchets up a so-far unsuccessful effort to reduce quakes related to oil and gas production.

The wastewater is pumped out of the ground when oil or gas is extracted, and then put back underground at what is known as a disposal or injection well. The instruction, issued late Monday, seeks a 38 percent cut in the amount of this wastewater being pumped underground by the operators of 23 injection wells, largely northeast of Oklahoma City.

The roughly 40-mile stretch that includes the wells has experienced a drastic increase in earthquakes in the last two years.

Those 40 miles are but one hot spot in a state that has seen a swift and relentless increase in earthquakes since 2010, triggered by a boom in energy production. Seismologists say the briny wastewater seeps into faults in rock far below the surface, effectively lubricating the cracks until the rocks slip, causing a tremor.