State officials propose extending limits on underground oilfield wastewater disposal

In the ongoing battle to reduce human-induced earthquakes in southern Kansas, state officials told the Harper County Commission on Tuesday that they want to add at least another six months to limits on underground disposal of oilfield wastewater.

The reduction that began phasing in six months ago is credited with reducing the severity of quakes that have rocked oil-producing Harper and Sumner counties for about the past three years.

Improved detection equipment has recorded 2,801 quakes in Harper County in the first nine months of this year, almost all of them too small to feel, said Rick Miller, a senior scientist with the Kansas Geological Survey.

Of those, 98 quakes were estimated in the “felt” category of magnitude 2 or higher, Miller said.

Officials of the Kansas Corporation Commission and the Kansas Geological Survey traveled to Harper County – the epicenter of Kansas quake activity – seeking to assure local officials and residents that steps are being taken to monitor and reduce the shaking.

Harper County Commission Chairwoman Carla Pence said that when she took office five years ago, she never dreamed she’d be leading meetings about earthquakes.

“It was not even remotely on the radar,” she said. “I always said I wouldn’t move to California, because while I can deal with tornadoes, I couldn’t deal with an earthquake.”

State geologists believe the seismic activity stems from disposal of the wastewater from oil production, primarily in Harper and Sumner counties. The salty, oily water is too polluted for practical above-ground disposal, so oil producers inject it into deep underground rock formations to get rid of it.

The geologists say the quakes are not a direct result of horizontal “fracking,” a process that uses high-pressure water and chemical mixes to fracture underground rock and free trapped oil. But it is related, because horizontal drilling and fracking has opened what was inaccessible oil to production, creating more wastewater as a byproduct.

The KCC issued an order in March limiting wastewater disposal to 25,000 barrels a day per injection well in Harper and Sumner counties and 8,000 barrels a day in seismically sensitive areas, said Ryan Hoffman, director of the commission’s conservation division, which deals with oil and gas issues.

So far, it seems to be helping, he said.

“We have seen a modest decrease in the amount of earthquakes within those areas, more specifically within those areas of seismic concern,” Hoffman said. “It’s a positive sign, and it’s encouraging to us that we’ve seen this. But at the same time, we know that’s not conclusive, and we still know there’s a lot left that we have to learn.”

The three-member KCC must approve the extension of limits on wastewater disposal.

Miller said the Kansas Geological Survey is tracking even the tiniest of earthquakes, as low as magnitude 0.1, hoping to establish a pattern.

“In theory, if you track the little ones, then you have some idea when the big ones are going to come or how big they might be,” Miller said.

“We’re seeing a lot more little ones and a lot fewer big ones,” he said. “We don’t exactly know why it is, but it is definitely positive.”

Meanwhile, Harper County residents are adapting to living on shaky ground.

John Gaffney, a lawyer in Harper, said he agrees with the scientists that the quakes “are not as severe as they were initially. I haven’t felt one in quite a while, actually.”

That’s a contrast to about a year ago, when his office got hit by one that shook the pictures off the walls – and scared some out-of-town clients who had never been in a quake before.

“I assumed the building would stand, and it did,” he said. “It’s a stout old building. But it scared us.”

Pence said Tuesday’s meeting came the day after her house was rattled by a quake, small in magnitude but whose epicenter was almost directly underneath her home about 10 miles from Anthony.

“After a while, you become kind of used to them,” Pence said. “But I won’t miss them when they’re gone. It’s kind of like a bad tooth.”

The biggest local concern is property damage, she said.

“I think a lot of people would tell you they’ve got cracks they never had before. We’ve had cracked foundations, walls, ceilings.”

She said she appreciated the state officials coming to Anthony to give an update on efforts to fight the quakes.

Some have learned to live with, and even laugh at, the threat of earthquakes.

After meeting with the state officials, the county commissioners moved on to planning their annual employee appreciation event.

As talk turned to the possibility of a family movie night, Commissioner Lee Adams quipped: “I know what we can do, we can get that movie ‘San Andreas.’ ”

This story was originally published September 8, 2015 at 6:16 PM with the headline "State officials propose extending limits on underground oilfield wastewater disposal."