Two natural gas exploration companies agreed Thursday to extend the shutdowns of two injection wells in Arkansas as researchers continue to study whether the operations are linked to a recent increase in earthquake activity, a state commission said.
Chesapeake Energy and Clarita Operating asked to postpone a hearing on the shutdowns before the Arkansas Oil and Gas Commission until April 26, said Shane Khoury, deputy director and general counsel for the commission.
The companies had been expected to present testimony to the commission on March 29, after the panel ordered the temporary shutdowns of the wells on March 4. The two injection wells are used to dispose of waste fluid from natural gas production.
"We were going to request that the wells remained shut down (at the meeting on March 29)," Khoury said. "(Both companies) requested a continuance on the hearing until April, and we agreed on the condition that the wells remain closed until that time."
Khoury has said preliminary studies showed evidence potentially linking injection activities with more than 1,000 mostly minor quakes in the region during the past six months.
Clarita Operating has said it does not agree with the commission and it believes the area's seismic activity is a result of natural causes. Clarita has not changed its position, Mickey Thompson, one of the company's partners, said Thursday.
"We still very much believe that the science needs to be heard before any conclusions are drawn," he said.
Thompson said the company is hoping its alliance with Chesapeake Energy, a larger company, will help strengthen its case. Chesapeake also says the earthquakes are likely a natural occurrence.
"The science continues to point to naturally occurring seismicity, but to ensure that we provide the most complete expert analysis, we have agreed with the commission staff to keep our disposal well temporarily closed until the ... April hearing," Danny Games, Chesapeake's senior director of corporate development, said in a statement. "We will continue to work with all parties involved for a resolution, and we are appreciative of the cooperation and constructive exchange."
The area has experienced a noticeable decrease in seismic activity since the injection wells have been closed, said Scott Ausbrooks, geohazards supervisor for the Arkansas Geological Survey. However, he said it is too early to tell if the two events are directly related.
The Center for Earthquake Research and Information recorded around 100 earthquakes in the seven days preceding the shutdown earlier this month, including the largest quake to hit the state in 35 years _ a magnitude 4.7 on Feb. 27. A dozen of the quakes had magnitudes greater than 3.0.
In the seven days following the shutdown, there were around 50 earthquakes. Since the wells were shut down, only two quakes have been magnitude 3.0 or greater. The majority were between magnitudes 1.2 and 2.8.