LITTLE ROCK — The Arkansas Oil and Gas Commission voted 8-0 on Friday to halt injections at two drilling-fluid disposal wells in Faulkner County for more than three weeks because of a possible link to an outbreak of earthquakes.
The two operators of the wells said they shut down Thursday in anticipation of the order, but will contest an extension of the shutdown.
Chesapeake Operating Inc. and Clarita Operating LLC dispute statements by commission staff members that there is a “potential correlation” between the wells and seismic activity in the area. More than 900 minor earthquakes in northern Faulkner County have been recorded since September.
Lawrence Bengal, director of the commission, said he asked for the order to halt the operations because of the discovery of a previously unmapped fault that was “highlighted” by recent seismic activity. The two wells are in or near the fault, staff members said.
A magnitude-4.7 earthquake hit Sunday night about 3 miles northeast of Greenbrier. Arkansas’ largest quake since 1976, it was felt in six states, though only minor property damage was reported.
The area has a history of seismic activity. Enola, roughly 20 miles southeast of Guy, was struck by small earthquakes that started in 1982 and continued off and on for a few years.
Scientists have been studying whether the recent temblors are linked to disposal wells used to abet hydraulic fracturing. Drilling for natural gas by using such fracturing began in the Fayetteville Shale in 2004. The formation runs across northern Arkansas.
Hydraulic fracturing is a process of extracting natural gas from underground shale formations by pumping millions of gallons of fluid into a production well, which breaks up the rock and allows the gas to flow out.
The disposal wells hold fluids used in the fracturing process. These wells are generally deeper and under pressure longer than production wells.
Shane Khoury, deputy director of the commission staff and its chief counsel, said the potential link between the wells and the seismic activity is not like “flipping on a switch,” where “you inject the water” and earthquakes immediately occur.
Bengal said the link is probably related to “the pressures, and the travel time of those pressures, through the rock and the volumes of fluid and how that’s interacting with the stress that’s in the rock.”
In January, the commission approved a six-month ban on new disposal wells around Guy and Greenbrier.
It required that operators of disposal wells already in the zone disclose to the Arkansas Geological Survey every two weeks the amount of fluid injected each day, and the maximum pressure. More recently, the data have included information on the amount or pressure of injections every one or two hours.
Friday’s emergency measure was requested because a longer-term ban required 10 days’ notice. Chesapeake and Clarita were notified Tuesday night.
The order lasts until the end of the commission’s next regular meeting, which starts March 29 and could last two days. Bengal said he will then ask for an extension and present evidence on the potential correlation.
The commission staff said in a release that there is circumstantial evidence that supports shutting down the wells for now.
Danny Games, senior director of corporate development for Chesapeake in Arkansas, said his company agreed to the order because it didn’t have time to prepare a presentation by Friday, such as securing experts for testimony.
According to the commission staff, Chesapeake is authorized to inject fluids 5,700 to 6,200 feet deep into its well, and Clarita can inject 7,800 to 10,900 feet deep.
The commission was informed Thursday afternoon that Chesapeake was voluntarily shutting in its disposal well until the next commission meeting.
“We remain confident that the facts and science will lead to a more constructive and satisfactory conclusion to this matter,” Games said in a statement.
Clarita voluntarily shut down its well Thursday afternoon, even as it maintained that facts and “scientific testimony” support that the earthquakes around Guy are the result of natural causes.
Chesapeake is the second largest natural-gas producer in the United States. Last month, it reached an agreement to sell its assets in the Fayetteville Shale to Australia-based BHP Billiton Ltd., the world’s largest mining company, for $4.75 billion. The deal is expected to close by July.
Clarita is a smaller company. “The impact of shutting in our disposal well is devastating,” Mickey Thompson, a partner in Clarita’s parent company, True Energy Services of Ada, Okla., said in a prepared statement.
Clarita has no gas production unit in Arkansas, and its 10 employees at the well were “without jobs” Friday, he said. The company has about 170 employees, most of whom are truck drivers.
The company says its business has been “seriously damaged, perhaps permanently, by the persistent negative comments published in the media,” mostly quoting commission staff, he said.
Even if there is a link between the quakes and the wells, the seismic activity won’t stop immediately after the wells are shut down, Khoury said, adding that it expects a lag time of two to three weeks.
The hearing was held at the Game and Fish Commission building in Little Rock. Among attendees were people who live the quake area.
Ricky Harrington, a Greenbrier resident for 51 years, who said he’s felt the temblors at home and at his business, believes they’re related to the wells, which he wants permanently shut down.
“This is bad for our community up there because of the simple fact of who’s going to want to move up there in the middle of earthquakes? Property values are going to go down, and damage is being done to these houses.” In some of the homes, “there are creaks in the house, doors won’t close, cabinet doors won’t stay shut.”
“That’s not going to bother the gas companies, and we’re still going to have problems.”
The commission staff members said their opinion of the situation is based on research by the state’s geological survey and the Center for Earthquake Research and Information at the University of Memphis.
A statement on the center’s website states that deep wastewater injection has caused earthquakes in two instances in Colorado.
“Although there is only circumstantial evidence that links current earthquakes with wastewater injection in central Arkansas, we are concerned that continued operation of injection wells in the seismic area risks triggering more and possibly larger earthquakes,” the center said.
Front Section, Pages 1 on 03/05/2011