November 30, 2013

To the Railroad Commission: Do more than study Azle quakes

Near-daily tremors in Parker County justify a review of seismic safety and well restrictions.

For 10 years, the counties around Fort Worth have shared the 100,000-plus jobs, economic development and wealth from horizontal drilling for natural gas in the Barnett Shale.

We enjoy and expect gas heat for our homes and electricity from gas-fired power plants. We ride on cleaner, natural-gas buses and cheer for America’s energy independence.

But with the success of the Barnett Shale has come increased concern over the proliferation of waste-water injection wells, particularly when homes west of Eagle Mountain Lake shook at least 20 times last month.

As of late last week, the earthquake swarm near Azle, Reno and Springtown had not caused an injury or even broken a dish, according to authorities in Parker, Tarrant and Wise counties.

But what began as microquakes grew to two magnitude-3.6 earthquakes, one of them inside Azle that was felt from Weatherford to Denton.

That’s getting close to the magnitude-4.0 that starts causing damage.

Four years ago, when microquakes hit Cleburne in Johnson County, they were considered more nuisance than nightmare.

City officials finally tired of the jitters and hired an academic expert to track the source. Eventually, without accepting responsibility, an energy company voluntarily closed two injection wells.

That was before a 2011 Oklahoma earthquake, a magnitude-5.6 jolt that injured two, wrecked a junior college administration building and 14 homes, buckled part of U.S. 62 and was felt as far away as skyscrapers in Dallas and St. Louis.

A University of Oklahoma study suggested that injection wells in an old oilfield near Prague, Okla., intensified underground pressure and caused greater seismic shifts than previously seen. But the Oklahoma Geological Survey disagreed, calling it a natural event.

Since then, the lead researcher at the University of Texas Institute for Geophysics has found a probable connection between North Texas injection wells and some recent microquakes.

And an Arkansas earthquake swarm eased after state officials ordered one well closed and energy companies voluntarily closed others.

Last week, even Ken Morgan of TCU’s Energy Institute told KXAS/Channel 5 that the earthquakes might involve wells “that could be pumping too much water out, or putting too many fluids in, industrial or municipal fluids.”

U.S. Geological Survey scientists have also found that the fivefold increase in central and eastern U.S. earthquakes in recent years is probably related to waste-water disposal.

That report suggested that cities, counties and states regulate wells based on seismic activity along with environmental safety.

That brings us back to Texas, and to Parker, Tarrant and Wise counties.

The Railroad Commission, led by an elected board, regulates the energy industry and the related underground storage of 1 billion barrels of waste water in 50,000 injection or storage wells, some no longer active.

The commission says it finds no “significant correlation” between quakes and injection wells but “welcomes more data.”

Even at that, Railroad Commission inspectors should be doing more to ensure that Texas’ wells are not pumping more than the licensed amount of waste water — up to 30,000 barrels a day at one of several wells near Azle — and that the licensed amount still makes sense.

Parker County commissioners and Azle city officials have asked the Railroad Commission to do more.

One microquake doesn’t hurt. But 20 earthquakes in a month, some of escalating intensity, can hurt property values and might discourage other industries from locating in an active seismic zone.

The people of Parker, Tarrant and Wise counties deserve a better answer than “we welcome more data.”

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