Oklahoma has shook, rattled and rolled through nearly 800 earthquakes in the past year, according to U.S. Geological Survey data.
That is more than enough for Cynde Collin-Clark, who is poised to leave her Edmond home for someplace without as much seismic activity.
“That’s all I can think to do anymore,” she said.
Questions remain about the source of Oklahoma’s earthquake swarm, but some studies have linked the temblors to wastewater disposal wells used by the oil and natural gas industry.
A number of area residents at a recent town hall meeting in Edmond called for a moratorium on disposal wells, although regulators said they do not have the authority to halt such activity. A seismologist with the Oklahoma Geological Survey also said additional data from disposal wells will benefit researchers.
Industry officials said disposal wells are a necessary part of oil and natural gas production, especially in Oklahoma.
A lot of water
Brian Woodard, the Oklahoma Independent Petroleum Association’s vice president of regulatory affairs, said water comes from the wellbore, along with oil and natural gas in areas like northern Oklahoma’s Mississippi Lime formation.
Wells there typically produce 10 times as much water as hydrocarbons over their lives, which can span decades. That leaves the industry to deal with a lot of water, considering the state produced about 10 million barrels of oil in April.
Produced water is many times saltier than ocean water. It also can contain toxic metals and radioactive substances.
“Water disposal underground is the most practical solution,” said Duane Grubert, executive vice president of investor relations at SandRidge Energy Inc., “given that water is produced from over a thousand square miles of productive acreage, and water treatment at the surface and subsequent transport of that water is both technically challenging and cost prohibitive.”
“Disposal remains the most economic method to date,” Grubert said. “Other treatment methods have yet to compete with what has been commonplace in the industry for decades.”
SandRidge has built a massive water disposal operation in northern Oklahoma and southern Kansas, with the capacity to inject about 2 million barrels of water a day into deep underground formations.
The company currently disposes of about 1 million barrels of water a day, according to its presentation at last month’s RBC Capital Markets’ Global Energy and Power Conference in New York.
Woodard said producers have been diligent in trying to reuse water in hydraulic fracturing operations with an eye toward preserving fresh water, but produced water poses a more difficult challenge because of its sheer volume.
Oklahoma producers injected more than 1 billion gallons of water into the ground in 2012, according to regulators. The Oklahoma Corporation Commission is compiling data on disposal wells to analyze trends.
Officials acknowledge it is more expensive to treat produced water, but are reluctant to get into specifics.
“We consider operations-related information to be commercially sensitive so I can’t specifically discuss water treatment costs,” Marathon Oil Co. spokeswoman Lisa Singhania said. “What I can tell you is that Marathon Oil is committed to environmental stewardship, including the responsible use of water resources.
“Marathon Oil continuously looks for ways to use less water in our hydraulic fracturing operations, including evaluating technologies for recycling and treating produced water for reuse in our operations.”
Re-using produced water
Bosque Systems LLC, a Texas-based water management company, focuses on helping producers get flowback and produced water ready for use in future hydraulic fracturing operations.
Peter Pappas, the company’s vice president of growth and business development, said the techniques Bosque uses vary around the country, but the goal is to help producers limit the amount of fresh water they use.
“It truly is dependent on what the chemistry of that water looks like,” he said.
Pappas said pressure pumping companies have improved their operations to make it simpler for Bosque and similar treatment companies to prepare water to be used in fracking.
“It’s easier to do today than it was five years ago,” he said.
Pappas said he expects the industry’s focus to remain on treating water so it can be used in completion operations as long as the current drilling boom continues. Processes that can treat produced water for industrial or other uses are more expensive at this point.
Coping with regulations
OIPA’s Woodard said there can be regulatory barriers to recycling briny produced water, which can be considered a hazardous material if it spills.
Woodard said producers in developing resource plays evaluate possible uses of flowback water as they consider the economics of their operations. Those that operate in Oklahoma and Texas have been blessed with access to the Arbuckle formation, which readily accepts fluids in high volumes, he said.
Woodard said there are alternatives to disposing of flowback water, but “each one of them has significant costs.”
He said halting the use of disposal wells, as some have suggested, would hamper producers.
“It would bar development in a number of plays,” Woodard said, as increasing costs overwhelm producers’ rate of return.
He questioned links between earthquakes and disposal wells, noting Oklahoma producers have been injecting water into the Arbuckle for eight decades. The state’s increased seismic activity started only the past few years.
The latest study by a group led by former University of Oklahoma researcher Katie Keranen suggested high-volume disposal wells can cause earthquakes more than 18 miles away.
Information like that has Edmond resident Collins-Clark looking for a new place to live. She said she just feels the area’s earthquake activity is here to stay.
“It doesn’t feel like it’s going to all of a sudden stop,” she said. “That makes me very, very sad.”
Collins-Clark said she is “profoundly saddened” to be leaving the home that she has shared with her husband for more than 17 years. He has been there for 26 years.
Collins-Clark said she hopes to move to a less seismically active area by August. She wants to stay close enough to maintain her counseling practice in Edmond, although she is semi-retired.
Collins-Clark said Oklahoma officials need to make immediate changes to how disposal wells are operated, making it a priority to protect lives and property.
“It needs to be done sooner rather than later,” she said.
CORRECTION: Incorrect names of the U.S. Geological Survey and Oklahoma Geological Survey were published in this story. (This story has been corrected.)
Water disposal underground is the most practical solution. ... Disposal remains the most economic method to date. Other treatment methods have yet to compete with what has been commonplace in the industry for decades.”
Executive vice president of investor relations