PURGE PROBE

What is causing a saltwater purge to the Earth's surface in northwest Oklahoma?

OMEGA — A purge of saltwater to the earth's surface happening on the BlaineKingfisher county line isn't slowing down.

The ongoing situation has prompted authorities to direct operators of four nearby saltwater disposal wells to remain shut in for at least another two weeks.

“This is the recommendation of a consultant we are working with and his estimation of how quickly the water is moving underground,” Matt Skinner, a spokesman for the Oklahoma Corporation Commission, said on Wednesday. “We need to give it more time before we undertake any additional actions.”

The commission's oil and gas conservation staff also has added a temporary additional restriction on what formations newly permitted disposal wells will be allowed to use across much of western Oklahoma, halting new disposal wells from putting water t he Permian formation.

Much of that temporary exclusionary zone, which covers 11,300 square miles, is inside a previously declared area of interest the agency created in 2015 that prohibited any saltwater disposal wells drilled within that area from that time forward from using the Arbuckle formation as a place to get rid of the water.

Existing wells, outside of the four that are shut in, are still being allowed to operate within certain parameters.

Besides taking the nearby saltwater disposal wells offline, Devon Energy previously also voluntarily plugged three nearby production wells that were inactive to eliminate them as potential sources of the saltwater coming to the surface at the purge location.

Skinner said the purge problem first was reported to the agency and its regulators on July 1.

In September, he said the purge was producing an average of 68 barrels of saltwater daily. On Wednesday, he said regulators haven't observed a decrease in that rate.

He also said the water, which is percolating to the surface through soil, continues to remain “hotter” than what had been getting disposed of in the injection wells that suspended their operations.

“It contains many, many, many times the chlorides of any water that is being injected,” he has said. “The working theory is, the water is picking those up as it works its way through a heavily-chloride laden formation, but that is just another piece of the puzzle.”

As saltwater continues to come up out of the ground,

the liquid is being diverted to a temporary holding area, where it is collected for disposal.

Skinner said in September that every purge is unique, and added that most, unlike this one, usually have been tied to nearby well activities.

Meanwhile, he stressed that the current leak so far hasn't affected any fresh ground or surface water sources used by area residents and their operations.

“There are still no signs of any issues with drinking water,” Skinner said. “The staff, the consultant and the industry are working together as we continue to look into this ongoing situation.”