— By CHRISTIN COYNE and JUDY SHERIDAN
PARKER COUNTY – Two earthquakes shook northeast Parker County early Saturday and Monday mornings, bringing the total number of earthquakes this month in the Azle area to 14.
A 2.9 magnitude earthquake south of Reno rattled the area around 3:45 a.m. Saturday, followed by a 3.3 magnitude quake several miles west of Azle around 1:45 a.m. Monday.
The recent spate of earthquakes in the area began on Nov. 5 and included a 3.6 magnitude shaking on Nov. 19.
Scientists say they aren’t sure what’s causing the swarm of earthquakes, though some believe oil and gas disposal wells may be contributing.
Cliff Frohlich, associate director and senior research scientist at the University of Texas Institute for Geophysics, recently studied seismographic data collected on the Barnett Shale from 2009-11 and hypothesized that earthquakes might be related to injection wells if certain conditions are met, specifically a nearby fault that is already under stress.
Parker County Commissioners voted Monday to have County Judge Mark Riley send a letter to the Texas Railroad Commission asking them to investigate any connection between the earthquakes and Parker County’s injection wells.
Parker County Fire Marshal Shawn Scott said the quakes were short in duration — a second or less to a second-and-a-half — and shallow in depth. In some cases they caused windows to rattle, he said, but there have been no reports of damages or injuries.
“If you remember a few years ago, when we felt the ground shaking, I think it was a 5.6 that shook Oklahoma City, that’s what we felt. So in the grand scheme of earthquakes, these have all been very minor.”
He reported “a lot of calls in the dispatch center.”
“I’ve had numerous calls,” Precinct No. 1 Commissioner George Conley said, “people concerned about the earthquakes and what we are going to do about it.”
“I’ve got one email right here, saying, ‘What concrete actions do you intend to take about these earthquakes?’”
Conley said he and the county attorney talked with State Rep. Phil King, who said they were going to do a study.
Scott told the court there is no standard insurance policy in the State of Texas that covers earthquakes, and that an additional rider must be added.
There is nothing the county can do at this point, Judge Mark Riley said.
“There’s no disaster structure at this point for what’s happening up there,” he said. “We can’t assist. Emergency management has no role. Obviously, if we reach some huge monetary damage, then ...”
“If something bad does happen — if a bad earthquake does happen — how would we respond to that?” Scott asked.
“You stay away from the hole,” Riley replied.
Other local response
The Upper Trinity Groundwater Conservation District, a groundwater regulatory authority for Montague, Wise, Hood and Parker counties based in Springtown, says it has been involved in ongoing studies relating to what, if any, role injection wells or fracking might have in the recent earthquake outbreaks in North Texas.
“We don’t have any authority to do anything about [the earthquakes],” General Manager Bob Patterson said. “We also don’t have any authority over hydraulic fracturing or injections wells. That’s all a function of the railroad commission.”
“Now we are definitely concerned about it because of the fact that it may affect groundwater. And so we’re doing extensive work with TCEQ, the railroad commission and about three different hydrogeological firms and looking into those issues. Plus we’re cooperating on the Environmental Protection Agency’s study on hydraulic fracturing as well as injection wells.”
“We are looking into it,” Patterson said. “There is no firm conviction at this point that it is due to either one of those processes. It’s too early to tell. There’s a lot of studying going on by different groups. In any case, it could be a serious problem.”
Study of the issue began following a number of earthquakes near Cleburne a couple years ago that were assumed by the public to be the result of the oil and gas industry, according to Patterson, who said the district is providing information such as the depth of ground water wells and aquifer layers to track the possible effect of fracking and injection wells.
“We don’t have the authority to actually do anything except supply some science to the railroad commission and to TCEQ,” Patterson added.
The district deals almost daily with the railroad commission on injection well applications, Patterson said.
“Even though it’s not within our authority, they have listened to a lot of our concerns and we have an oil and gas consultant that tells us when they make an application for an injection well. We go over the depths, we go over the pressures, we go over the completion process, all of those things to determine if it looks like there is a question of it creating a problem for groundwater. We’ve been doing that for a number of years now.”
“When you present some good information to the applicants, a lot of times, they’ll revise the applications and move on,” Patterson said. “That’s been the case in every situation so far. So we’re watching that closely, and, hopefully, we’ll have enough good science to present to the railroad commission by the midpoint of next year that we hope we’ll get some new rules proposed.”