The Texas Railroad Commission, the state agency that regulates oil and gas drilling, declared on Friday that it found no evidence that a record 4.0 earthquake that struck North Texas last month was caused by injecting oilfield waste into underground wells.
“While we can’t say at this time there is a connection,” said Craig Pearson, the agency’s in-house seismologist, of the Johnson County tremor, “this is the beginning of the process, not the end in analyzing and understanding whether there is any correlation and what, if any action by the Commission may be necessary in the future to protect public safety and our natural resources.”
The Johnson County quake, which struck on May 7, was not one of the tremors studied by researchers who had declared in April a link between the disposal of fracking-related material and a swarm of earthquakes in the Fort Worth area. At the time, I wrote about how Texas policy-makers received that news:
“Key decision-makers have said there’s no clear link, including the head of a House subcommittee on seismic activity and the director of the Texas Railroad Commission, which regulates the oil and gas industry.
“‘This is not the definitive study,’ state Rep. Myra Crownover, who leads the House subcommittee on seismic activity, said of this week’s report by Southern Methodist University researchers.
Asked what it would take to change her opinion, she said, ‘In medicine, you have peer-reviewed science. You and I can speculate to anything.’
When told the SMU study, co-authored by scientists at the U.S. Geological Survey and the University of Texas and which relied on some industry data, was published in a peer-reviewed journal, Nature Communications, she said the issue ‘is fascinating, and requires more thought.'”
At the time, a Railroad Commission spokesman said the state agency, which regulates oil and gas drilling, “takes the issue of induced seismicity very seriously.” Its executive director invited the researchers to brief the agency’s commissioners and the agency’s seismologist said he was reviewing the SMU report.
Last week, XTO Energy challenged the SMU report, arguing before state regulators that it was not responsible for earthquakes that shook the towns of Reno and Azle in late 2013 and early 2014.
The university researchers did not participate in that hearing, issuing a statement that they would not provide comments “on any non-peer reviewed science being presented at the hearings.”
“We remain confident in the conclusions presented in our peer-reviewed publication, which was based on multiple lines of evidence,” they said.