A white Chevy Suburban with “Railroad Commission of Texas” emblazoned on its side rolled north on Interstate 35. Behind the wheel sat Milton Rister, the commission’s director.
Trim and balding, Rister was a veteran political operator who had held influential positions in the Texas Republican Party for decades. He could smell political disaster from miles away – and this one reeked. As he neared the town of Azle, northwest of Dallas, Rister said to himself: Please let there be only 50 people there.
For weeks, telephones at commission headquarters in Austin had been ringing about earthquakes hitting Azle, which had never felt a quake before. Suddenly, ground was shaking under hayfields and homes, rattling windows, knocking pictures off shelves, and sending frightened children into their parents’ beds at night. One woman said her hens had quit laying eggs.
With more than 20 tremors in two months, locals wanted to know: were oil and gas operations causing this? What was the state’s energy regulator, the inaptly named Railroad Commission, going to do about it?
As the Suburban pulled in front of Azle High School, Rister surveyed the scene with dread. He had arrived an hour early for a public meeting on the quakes, but cars already filled the parking lot. A line of news trucks pointed their satellite dishes skyward.
Not good, Rister thought. His agency had no answers for the nearly 900 people packing the auditorium.
After an hour and a half of hostile questions, the sole railroad commissioner present disappeared down a back hallway. In damage-control mode, Rister stood before reporters.
“Obviously these folks have experienced traumatic events, and we recognize that,” Rister, then 62, said in his mild Central Texas accent. “We’re going to go back and take what we learned tonight from these people, work with the experts that are doing studies, and see if we can come up with the next step.”
In the end, that’s not what happened.
The meeting in Azle, on Jan. 2, 2014, pitched the Railroad Commission into a political crisis that would intensify over the next two years as more earthquakes rumbled across North Texas.
Top scientists, meanwhile, piled up evidence that the quakes were triggered by a byproduct of oil and gas production. Wildcatters had discovered they could pump millions of gallons of chemically treated water and sand into natural gas wells at extreme pressure to fracture rock and let gas escape. They combined that technique – fracking – with other technological advances to turn the U.S. into one of the world’s top energy producers.
But the process also produced toxic wastewater that was hard to get rid of, especially without threatening drinking-water supplies. So drillers opened wells in pastures across the countryside to bury the byproduct thousands of feet underground.
It was no coincidence, academic experts said, that the shaking occurred as wastewater disposal in North Texas soared from a few hundred thousand barrels in 2005 to more than 200 million barrels a year by 2013. Some experts have estimated that most of this fluid was from the fracking process itself.
The federal government weighed in, finding that earthquake rates had spiked in a half-dozen energy producing states including Texas – and that those earthquakes were primarily man-made.
But even today, the Railroad Commission has yet to publicly accept that finding as more than a possibility. The commission, while calling for “sound science,” has disregarded, downplayed and at times disparaged the scientists’ work.
Historically, the three elected commissioners have moved in step with oil and gas companies. Industry contributions fill their campaign war chests and industry operations fund most of their agency’s budget.
The commissioner who has shaped much of the agency’s response to the earthquakes is Ryan Sitton, an energy executive with political ambitions. He has collected more than $700,000 in campaign contributions since taking office in 2015, mostly from executives of oil and gas companies. One of them lent Sitton his private jet.
In one instance, Sitton accepted $20,000 from the CEO of a company just as commissioners weighed whether to hold it responsible for North Texas quakes.
“The notion that those dollars would influence me to do anything other than what I thought was the right thing to do is somewhat preposterous,” Sitton said in an interview with The Dallas Morning News.
As for the link between quakes and disposal wells in Texas, he said, “Unfortunately in the world of science and research, we very rarely have things that we consider to be conclusive.” So far, he added, “there’s been a large amount of assumptions, simplistic analysis and hypothesis in place of real data.”
The commission says it has addressed the possibility of future earthquakes by imposing new regulations on disposal wells in quake-prone areas. And the agency’s staff has negotiated with companies to curb the volume of wastewater at certain wells, and reduce the depth of two others.
For most of his adult life, Brian Stump had studied the shaking created by underground explosions. From his office at Southern Methodist University, he used a global array of seismometers to monitor nuclear tests like those set off by North Korea.
When tremors first started troubling North Texas in 2008, he began to investigate. He’d grown up in California and was used to feeling the earth shake. But not in Texas.
Scientists had known for decades that pumping fluid deep into the earth could disturb geologic faults. Stump and other researchers began collecting data that linked two clusters of quakes in North Texas to disposal wells nearby. In both cases, the operator shut the wells down.
After Azle, Stump, then 62, began putting together a team to study those quakes. Among the SMU faculty he sought help from was Heather DeShon, 36, a seismologist who had been fascinated by earthquakes and volcanoes since childhood and had studied them in the U.S., Costa Rica, Indonesia and – with the help of a satellite – even on Venus.
Another team member was Matt Hornbach, a 38-year-old geophysicist who grew up around Dallas. Specializing in how fluids and heat move through the earth, Hornbach spent months at a time at sea studying pressure changes beneath the ocean floor.
They wanted this study to be different. Until then, quakes in Texas had been linked to disposal wells mainly by proximity and timing. This time, the SMU team also wanted to understand how much pressure was building underground near the bottom of the disposal wells and in the surrounding rock. Was it enough to trigger movement along a fault?
Post Azle, Rister and the commissioners decided they needed to hire a seismologist. They settled on Craig Pearson, a 55-year-old from West Texas who had worked for Halliburton, a drilling company.
Pearson also had ties to the SMU scientists. He had earned a doctorate at the university under Stump and the pair had done seismic research together.
The commission touted Pearson’s hiring as evidence that it would embrace science. He explained to legislators how underground pressure from disposal wells can cause faults to slip. But he stopped short of conceding that had ever happened in Texas.
He helped create new rules allowing the commission to shut down wells suspected of causing earthquakes – though it has not permanently closed any wells.
Inside his office at SMU, Hornbach considered the forces that could disturb a fault. Natural earthquakes were unlikely given the Azle area had never felt them before.
But to understand the pressure changes caused by the disposal wells, Hornbach needed data from energy companies. How much wastewater were they injecting? How fast? At what pressure?
Railroad Commission regulations require companies to release only the barest information about their disposal activities – and only once a year.
Hornbach and his colleagues zeroed in on two wastewater wells closest to the epicenters of the Azle quakes. One was operated by EnerVest and the other by XTO Energy, a subsidiary of ExxonMobil. XTO started providing data, sharing daily injection pressures and volumes and helping the scientists map the fault that had shifted beneath Azle.
Sitting at his computer, Hornbach could watch his model come to life on screen. He clicked his mouse on a bird’s eye view of the two wastewater wells. A small red dot – a point of high pressure – appeared below the XTO well. As time passed, the dot grew and spread out like a drop of water on a napkin. Soon, a second dot appeared below the EnerVest well.
Finally, before the quakes started in November 2013, the two dots merged into a giant crimson blob.
Hornbach ran the model dozens of different ways and found that, in every case, pressure built to a high point soon before earthquakes first struck Azle. Based on previous studies, he knew the pressure change was great enough to activate a fault.
The model bolstered the conclusion that oil and gas activity had most likely triggered the quakes. Hornbach, DeShon, Stump and eight other researchers at three institutions – SMU, the University of Texas and the U.S. Geological Survey – submitted their study to a journal, Nature Communications. If the paper survived a peer review by independent experts, it would be published.
But Hornbach didn’t foresee the pushback that would come from the Railroad Commission and its newly elected member, Sitton.
At 39, Sitton had short blond hair, a photogenic smile and an air of unlimited self-confidence. He’d worked in energy since earning an engineering degree in 1998 from Texas A&M. In 2006, he and his wife had started PinnacleAIS, a company that helped refineries ensure that pumps, tanks and other equipment stayed reliable.
After an unsuccessful bid for the statehouse, Sitton jump-started his Railroad Commission campaign by lending it $1 million. Then he began repaying himself with contributions from oil and gas executives. This included $10,000 from EnerVest’s CEO and equally handsome sums from a long list of others.
During his campaign, he told a reporter he hadn’t seen any research to suggest disposal wells were related to earthquakes.
“When you consider the volume of earth that is affected in a disposal well and in a frack job and the pressures that we are talking about,” Sitton said, “it seems highly unlikely that those are having a direct impact on seismic activity.”
On Jan. 6, 2015, the day after Sitton was sworn in, a magnitude 3.5 earthquake struck North Texas. This time, buildings in downtown Dallas trembled, startling a city that had never felt a quake.
The quake was followed four hours later by another, slightly stronger one and then several smaller tremors.
Hundreds of residents later packed Irving City Hall for a meeting about the quakes. Members of the SMU team said it was too early to know what caused them _ the nearest disposal well appeared to be about 10 miles away. Still, previous studies showed wells could trigger tremors from such large distances.
The Railroad Commission’s new seismologist, however, said he had an answer:
“The evidence points to no injection well being a likely cause of these earthquakes,” Pearson told the crowd, while acknowledging he did not conduct research like the SMU scientists.
On April 21, 2015, the Oklahoma Geological Survey acknowledged that a surge in earthquakes in that state was probably tied to the proliferation of disposal wells.
At 10 a.m. that same day, Nature Communications released the scientists’ paper concluding that energy activity had most likely caused the quakes in Azle.
A media strategist for the oil and gas lobby had already begun emailing reporters. Before noon, he posted a column on a website sponsored by the Independent Petroleum Association of America.
Railroad Commission officials were far from admitting that disposal wells in Texas were causing quakes. But with the Nature Communications paper out, they knew they had to do something.
Inside a conference room at commission headquarters, Rister huddled with several top staffers to figure out the next step.
By the end of the day, two commissioners – Christi Craddick and David Porter – had agreed to call formal “show cause” hearings. The oil companies operating disposal wells near Azle – XTO and EnerVest – would be summoned to testify about why their wells shouldn’t be shut down.
Commissioner Sitton didn’t believe these hearings were necessary. He wanted instead to hold a less formal meeting at which the companies and the scientists could discuss the findings.
Though it was two against one, Sitton decided to move forward with the informal meeting on his own. So the divided agency set in motion both his meeting and the show-cause hearings.
On a Friday morning in early June 2015, the SMU scientists walked two blocks from a Hampton Inn to the government high-rise where the Railroad Commission has its headquarters to attend Sitton’s less formal gathering.
Inside a meeting room on the 12th Floor, they took seats along a wooden conference table. Seated around them were Sitton, three EnerVest executives and others.
After asking everyone to introduce themselves, Sitton opened the conversation with an acknowledgement that fluid disposal was known to have triggered quakes decades ago in Colorado. He said the meeting was part of his effort to “make sure anything that we do here is going to be based on good, sound science.”
SMU’s DeShon, one of the paper’s lead authors, began clicking through PowerPoint slides. The presentation featured seven questions to ask in determining whether earthquakes were man-made. Had there been quakes in the area before? (No.) Is there a clear correlation between injection and seismicity? (Yes.) Are pressure changes at well bottoms enough to encourage seismicity? (Yes.) And so forth.
One disagreement quickly emerged. Hill and EnerVest argued that the initial quakes in Azle occurred far deeper underground than the injection wells reached. To them, that showed the wells weren’t to blame.
The paper’s authors had heard this argument before. But EnerVest’s analysis had not been peer-reviewed, which to the SMU researchers meant it was unvetted. And in any case, they knew that scientists elsewhere had shown that pressure could migrate deep below a well, possibly through faults and fissures.
Much of the four-hour discussion was cordial but tense. The paper’s authors had hoped to discuss how best to address the quakes, which might involve decreasing certain wells’ wastewater volumes. Instead, the talks were mired in debate over the quakes’ cause.
EnerVest, meanwhile, had much at stake. Its only injection well in North Texas faced the threat of a shut-down. Trucking all that wastewater elsewhere would cost between $2,100 and $4,200 a day, the company estimated.
At one point in the meeting Hornbach and an EnerVest executive began talking over one another about pressure measurements.
Pearson, the commission’s seismologist, broke it up. “I’m going to step in here and say this is enough,” he said.
The meeting soon ended, with each camp pledging future collaboration. Before leaving, Pearson spoke to a reporter, saying he disagreed with the scientists. “I have not reached the conclusion that oil and gas activity is the causal factor,” he said. Pearson said he planned to respond in detail in a letter to Nature Communications. He never did.
Rister decided it was time to make a deal. The Railroad Commission did not want to look like it was doing nothing, and the companies didn’t want to shut down disposal wells important to their business. Nor did they want to become vulnerable to lawsuits from homeowners blaming them for foundation cracks and other quake damage.
Together they came up with a plan, Rister says. Without admitting fault, but out of an abundance of caution, the companies would cut their disposal volumes by half. By this time, XTO, which owned the highest-volume well, had already reduced its injection anyway because it was handling less wastewater, according to the company. The quakes in Azle had subsided. Over time, if the earth stayed quiet, the companies could slowly turn the volumes back up, under the proposed deal.
After several meetings with XTO and EnerVest lawyers, Rister took the idea to his bosses – who quickly vetoed it.
Rister called his contacts at the oil companies:
Looks like you’re going to the formal show-cause hearing. Get ready.
The Railroad Commission’s hearing room in Austin is laid out like a courtroom. Two de facto judges – commission hearing examiners – dressed in dark suits, sit in high-backed leather chairs behind a long, wood-paneled desk. A commission seal hangs on the wall behind them.
Across from them is a long table for the lawyers. On June 10, 2015, it was lined with XTO lawyers and their oil-executive witnesses. The table was filled with legal pads and presentations and accordion folders full of exhibits.
At the table’s far end sat a lone lawyer for the commission. If this were a criminal trial, he would be the prosecutor. He sat by himself, with no witnesses and only one exhibit – the well’s permit file. He passed up the opportunity to make an opening statement.
Pearson says he wasn’t invited. The Azle study authors received a hearing notice but didn’t feel it was their role to get involved in a regulatory agency’s legal proceedings. They believed their paper stood on its own.
So one of XTO’s lawyers began. He spent 10 minutes previewing his arguments, giving a summary of the dozens of slides, exhibits and witness testimonials coming during the next seven hours.
At one point the lawyer called a company executive to address the scientists’ paper in Nature Communications. After sharing a laugh, they began, lawyer and oil executive, tearing the paper apart point by point.
In an email to The News recently, an XTO spokeswoman said the company continues to believe the scientists’ Azle paper was flawed and that “regulatory permitting decisions should be based on science and not on a study that hypothesizes causation with a high degree of uncertainty.”
Commissioner Craddick, in an emailed statement, defended the process and cited the commission’s rules on disposal wells as evidence the agency is working “to keep our citizens and resources safe.”
Reflecting on the events, SMU’s Stump said the Railroad Commission and the oil companies set a high bar for linking the earthquakes to disposal wells.
“The fluids went down Hillcrest and took a right on Lovers Lane and that the pressures arrived at 12:07 on this part of the fault – we’re never going to be able to do that,” he said.
After heated disagreements with his bosses, Rister retired as the commission’s director. One of his big disappointments, he says, is that the episode that began in Azle ended without “anybody looking like we cared about the public.”
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