Fracking Texas, Recycling ‘Flowback,’ & Water Contamination

fracking wilson county texas
Drilling rig and flare operating beside a residential home in Wilson County, Texas. Image Credit: Greg Harman

Billions of gallons of water are wasted each year to fracture shale formations around the country and free trapped oil and gas. After the water is shot down a well, it returns to the surface heavily contaminated with hydrocarbons, fracking chemicals, heavy metals, and radioactivity. After the oil and gas is separated out, the water typically can’t be used safely for anything else. In Texas, that means it is usually shot down any of an increasing number of disposal wells.

In a state nestled deep in ongoing drought, that doesn’t go unnoticed. Neither do the earthquakes linked to the disposal operations.

This week, the University of Texas at San Antonio and Southwest Research Institute announced they are jointly investing $200,000 in research efforts to come up with a way to clean up fracking’s polluted flowback water.

Reads the UTSA news release:

UTSA mechanical engineering faculty member Zhigang Feng and SwRI senior research scientist Maoqi Fengbelieve that they can alter biochar derived from wood chips to create an economical and environmentally friendly solution. Produced from pyrolysis of biomass, biochar is a stable charcoal-like solid that attracts and retains water, absorbing up impurities such as hydrocarbons, organics, biocides and certain inorganic metal ions.

Over the course of the study, the researchers will isolate, prepare and characterize the biochar; test the biochar on flow-back water samples from the Eagle Ford shale; develop computer models of the biochar water treatment system; and assess the biochar’s performance for possible improvements.

If successful, they expect the biochar treatment to be the second step of a two-step water purification process. The first step would include filtration to remove the solids in the water remaining from the fracking process. The treated water would then be ready for re-use or safe disposal.

While none of the water used to frack in South Texas’ Eagle Ford shale play was being recycled when UT researchers surveyed fracking operations recently, about 90 percent was being recycled in Pennsylvania, where regulations are tighter.

Recently, I was told operators across South Texas have begun to use less drinking-water-quality water for fracking, and have even begun to recycle some. However, recycling water does nothing to address the Big Fear about fracking: the contamination of freshwater aquifers.

While the U.S. EPA has vacillated on this point, a new report (pdf) shows indications that water wells in Pennsylvania’s Marcellus Shale, at least, have been contaminated by fracking.

Writes Stephen Leahy at DeSmog Canada:

Researchers at Duke University were the first to independently study water contamination. In 2011 they looked at 68 fracking sites in the Marcellus shale region in the northeast US. They found groundwater with methane concentrations 17 times higher than in wells located where fracking was not taking place. Some of the recorded amounts were higher than “immediate action” hazard levels.

This year Duke researchers wanted to trace back the source and cause of the water contamination. They analyzed the concentrations and special ‘chemical fingerprints’ of methane, ethane, and propane in 141 private water wells in six counties in northeastern Pennsylvania and southeastern New York. The fingerprint work is key to knowing if these gases came from natural sources or were the result of fracking. 

Of the 141 water wells measured within one kilometre of drilling operations, 82% contained high levels of methane. Twelve of these wells showed “immediate action” hazard levels. About one third also had high levels of propane and ethane. Both are hazardous and flammable gases.

The cause of this widespread contamination is likely poor well construction, said Jackson. Unlike conventional gas production, fracking uses very high pressures. It is likely faulty steel casings and poor cement sealing were behind the leakage into nearby waterwells he said.

Others have reviewed the same report and come away less flustered.

Scott Johnson at Ars Technica suggests the finding — which targeted the presence of the deeper Marcellus Shale’s briny water (which includes methane, etc.) in shallower drinking-water aquifers — shows likely migration from those deeper aquifers, but not fracking contamination, per se.

“The effect could be minor—figuring that out will take a lot more work,” Johnson writes. “However, the Las Vegas assumption that what gets injected in the Marcellus stays in the Marcellus—at least in northeast Pennsylvania—appears not entirely valid.”

Faulty casings and poor well construction is something Texas has suffered from ever since Spindletop. However, new rules adopted by the Texas Railroad Commission in May that require pressure-testing those casings at fracking-related pressures, among other things, are intended to address those issues.

“Overall this is a very important rule that sets a higher bar for both traditional and hydro-fracking well drilling and casing,” Cyrus Reed, conservation director of the Sierra Club, told the Texas Tribune recently“We hope that this first good step will be part of a general move by the Railroad Commission of Texas to continue to upgrade their rules on injection wells, recycling of water and venting and flaring.”

While those are important rule changes, their implementation, effectiveness, and the ability of the RRC to enforce them remain to be seen.

And they do little, if anything, to stop ozone-forming air pollution that so concerns San Antonio residents or the release of large quantities of methane, a potent greenhouse gas, expected to grow exponentially worldwide as fracking operations expand.

Saddest fracking story ever? There are certainly many, but this week’s loser falls to New Mexico, where drought-plagued farmers in hock because of decimated crops are selling off their remaining water to stave off the bill collectors.

fracking texas
Same house as above, with a better view of an oilfield flare operating within sight of a child’s playground. Image Credit: Greg Harman