EarthquakesTexas acts to reduce number of man-made earthquakes

Published 31 October 2014

The number of disposal wells in Texas has surged along with the number of drilling projects. Texas has more than 3,600 active commercial disposal wells. In 2013, the Railroad Commission approved 668 disposal well permits, twice the number of approvals in 2009. The growing number of disposal wells corresponds with an increase in earthquakes in communities where such seismic activity rarely existed.Officials in Texas have now taken steps to reduce the number of earthquakes caused by wells drilled for the disposal of oilfield waste.

Officials in Texas have taken steps to reduce the number of earthquakes caused by wells drilled for the disposal of oilfield waste. The three-member Texas Railroad Commission voted unanimously to pass new rules which will require companies to submit additional information, including historic records of earthquakes in a region, when applying for disposal well drilling permits. The new regulations also affirm the commission’s authority to slow or halt injections of oilfield waste into vulnerable wells and require companies to disclose the volume and pressure of their injections more frequently.

The Texas Tribune reports that Commissioner Barry Smitherman called the vote a “textbook example” of how the commission identifies an issue and “moves quickly and proactively to address it.” The Environmental Protection Agency last month expressed support for the bill, and so did a few mayors of affected cities. “The proposed regulations were reviewed by multiple Ground Water/Underground Injection Control program engineers and scientists,” William Honker, head of the water quality division in Dallas-based EPA Region 6, wrote this month in a letter to the Railroad Commission. “All applauded the RRC’s efforts to ensure it has sufficient regulatory authority to respond to any event of the type where concerns may arise.”

The number of disposal wells in Texas has surged along with the number of drilling projects. Texas has more than 3,600 active commercial disposal wells. In 2013, the Railroad Commission approved 668 disposal well permits, twice the number of approvals in 2009. Environmental advocates point out that the trend does correspond with an increase in earthquakes in communities where such seismic activity rarely existed. In the past year, roughly thirty-six earthquakes of magnitude 2.0 or higher have struck communities near North Texas’ Barnett Shale. Drilling areas in South and West Texas have also experienced an increase in earthquakes. As more seismic researchers connect drilling of disposal wells to earthquakes, mayors of affected communities are calling on state officials to issue better regulations to curb drilling in vulnerable areas.

In April, the Texas Railroad Commission contracted seismologist, Dr. David Craig Pearson, to study the issue and help develop the new drilling rules. “My objective is to develop a broad understanding of the impact of oil and gas extraction activities on the day-to-day lives of Texas residents,” Pearson said. “I believe the Railroad Commission must be able to quickly and factually determine the accurate location of all earthquakes in the state and be able to determine the cause of earthquakes, be they natural or man-made.”

“What they did, I think it’s acceptable,” Alan Brundrett, the mayor of Azle, said in an interview last month, after he called for more comprehensive seismicity tests. “It wasn’t every recommendation that we had, but it was quite a few of them.”