A number of studies have been conducted in recent years by seismologists, indicating that the increase in earthquake activity in East and North Texas is related to an increase in fracking, particularly the injection wells that are used to dispose of oilfield waste.
For example, since 2011, the small town of Timpson, in Shelby County, has experienced a number of earthquakes, some measured as high as 4.8 on the Richter Scale, and has caused minor property damage and scared some residents into moving away.
Because of this, the Texas Railroad Commission this week voted unanimously to strengthen the rules for injection wells. From now on, companies that wish to drill an injection well will have to include additional information when they apply for a drilling permit. Among the information they will have to provide will be the historical records of earthquakes in the region in which they want to drill.
Once the well is in use, companies will be required to disclose to the commission in volume and pressure of their injections more frequently. In addition, the commission now has the power to stop or slow activity in an injection well that they consider to be a problem.
The number of disposal wells throughout the state of Texas has spiked during this latest oil and gas boom. In all, there are more than 3,600 active commercial disposal wells in the state, and the number keeps increasing. For example, the Railroad approved 668 permits for disposal wells in 2013, a number that was more than double the number of approvals in 2009. Unfortunately, during the same period of time, the number of earthquakes in communities that had never had a problem with earthquakes also spiked.
Just within the past year, the Barnett Shale in North Texas has experienced nearly 40 earthquakes with a magnitude greater than 2.0 on the Richter scale. A number of the quakes were strong enough to create cracks in the foundations and walls of a number of homes and other buildings. In September, three earthquakes shook up the Dallas-Fort Worth area, awakening some residents there from their sleep. Earlier this month, an earthquake measuring 2.2 on the Richter scale shook an area near Irving.
South and West Texas also have experienced an increased number of earthquakes, including a 3.2 magnitude temblor on Sept. 10 that shook up an area just south of San Antonio.
The Railroad Commission’s decision to modify the rules stems from some harsh criticism they received from several politicians in North Texas about the agencies slow reaction to the problem. Back in January, the commission hired a seismologist to take a look at the problem, and those recommendations were incorporated in the new rules.
The Texas Oil and Gas Association approves of the new rules, and the added effort to stem the tide of earthquakes in the state. It’s a good move, but will it be enough to stop the problem altogether? We still don’t know the long-term effects of a sustained series of small quakes on the structure of our homes, schools and places of work.