“Oil serves you every minute of every day” reads a sign on the door of a pickup owned by the Nebraska Oil and Gas Conservation Commission. And that service comes with some byproducts, according to Stan Belieu, the commission’s deputy director.
“For every barrel of oil you produce you produce about 100 barrels of water. And our regulations require that this water be injected underground. And so the wells that we’re going to go inspect are those wells that will be injecting that salt water that comes from the production of this oil,” Belieu said.
With Belieu in the pickup is Mike Sutton, one of the commission’s two field inspectors. On a hot summer afternoon near Sidney in western Nebraska’s panhandle, Sutton points to one of the wells where the waste water is injected back into the ground. “This would be the injection well itself, and he’s got a gauge on that which is reading zero. That’s good,” Sutton said.
Good, because it shows there’s no movement of fluid in or out of the cement-coated steel piping as it passes through hundreds of feet of the drinking water aquifer, on its way to 7,000 feet below ground. Before Sutton opens the hatch on a tank where this waste water is stored and filtered prior to injection, Belieu provides a reminder of one reason you want to keep this stuff away from drinking water.
“The thing that you worry about in tanks is H2S (hydrogen sulfide). So you don’t want to be breathing right now,” he explained.
And Belieu says there’s a lot of this water to be disposed of. The commission’s two inspectors try to check each of the 657 injection wells in Nebraska once a year, or more frequently in sensitive areas, Sutton explains as he shows another well. “This well would be close to Sidney, and it’s in that wellhead protection area. So these are the ones that’s done quarterly,” he said.
Sutton says such wells surround a lot of Nebraska communities where oil is produced. “They’re all around Kimball, all around Dix, all around Sidney, all around Scottsbluff, all around Gering, all around Minitare,” he said. “Anywhere there’s oil production, there has to be these kind of wells,” Belieu added.
Belieu says most people from oil producing areas don’t think much about the wells. But a proposal to convert an old oil well in Sioux County for disposal of water from Colorado and Wyoming sparked controversy earlier this year. The commission’s approval of a scaled-back version of that proposal is now being appealed in the Cheyenne County District Court.
Issues involving disposal wells are not confined to western Nebraska’s panhandle. Sidney, where the Oil and Gas Conservation Commission is headquartered, was a hotspot for oil well development for three decades starting in the late 1940s. Now, Belieu says, the focus has shifted to southwest and southeast Nebraska. “The real oil activity is in southwestern Nebraska around the McCook area and Hitchcock, Dundee Counties along the Kansas border …and where the original oil was discovered down in Richardson County and Falls City there’s a lot of activity and a lot of drilling going on down around there,” Belieu said.
There’s also the potential for earthquakes in southeast Nebraska. That area of the state is part of a geological formation known as the Nemaha Uplift, which stretches to Oklahoma. As more and more waste water from oil drilling has been injected into the ground in that state, the number of earthquakes has skyrocketed.
In 2007, Oklahoma had exactly one earthquake of magnitude 3.0 or greater. Last year, it had 584. But Nebraska Oil and Gas Commission Director Bill Sydow says that increase is not necessarily linked to injection wells. “Where these earthquakes are happening is on top of the Nemaha Uplift or the Nemaha Ridge. And in the 1950s there was an earthquake swarm that was very similar to this, that went away. So this could be tied to that deep well disposal, or it could be a naturally occurring event and it’ll go away,” Sydow said.
University of Nebraska-Lincoln geology professor Cara Burberry is skeptical. She says if too much waste water is injected into the ground, that will increase the risk of earthquakes, like what’s happened in Oklahoma.
Burberry relies on what she says is the widely-accepted geological theory known as plate techtonics. Sydow favors a different theory. “There are fatal flaws in plate techtonics that people don’t get taught,” he said. “I personally like surge techtonics.”
Surge techtonics emphasizes the effect of magma flows in shaping the underground world and affecting earthquake activity. Burberry acknowledges some predictions based on plate techtonics have been wrong. But she says relying on surge techtonics could discount real risks posed by waste water disposal. “If you come from a framework where earthquake activity is caused by surges of magma, then my understanding of that theory doesn’t allow for any other mechanism of generating those earthquakes,” she said. “In a more plate techtonic-style framework, you would explain by what I would characterize as ‘overenthusiastic’ deep well injection, i.e. pumping too fast, pumping too much.”
Sydow says Nebraska’s oil and gas commissioners don’t have to determine which theory is right to evaluate risks from injection wells. “The commission is going to deal with the physical, geological facts that we are presented with, and however they got there is absolutely superfluous,” he said.
And Sydow says the commission can reduce risks of earthquakes or drinking water contamination by carefully calibrating what it allows injection well operators to do. “We want to be aware of that potential and we want to mitigate, as we always have, any potential for anything in a negative sense to happen by regulating that surface injection pressure,” he said.
Whether that will continue to be the commission’s responsibility, or whether a different agency should take it over, is among subjects a legislative committee will study later this year.