Some 8,000 feet deep and 450 million years old, the Utica Shale has a lot of petroleum — crude oil, natural gas and byproducts like ethane.
Although no one really knows how much there is, oil and gas companies are flocking to eastern Ohio, home to some of the shale’s most amenable portions.
“Right now we’re still in an exploratory phase,” said Brian Hickman, a spokesperson for the Ohio Oil and Gas Association.
It’s also an experimental phase for the technology that makes shale extraction possible, Hickman said. Companies that have used horizontal hydraulic fracturing successfully in the Marcellus, Barnett and other shales are still trying to figure out how to best use it in the Utica.
In Ohio, 65 Utica Shale wells have been drilled so far, each requiring 5 to 6 million gallons of water, said Heidi Hetzel-Evans, a spokesperson for the Ohio Department of Natural Resources.
But as Utica drillers analyze early results, at least one company thinks water might be unnecessary — or even a hindrance — and that using a waterless, propane-based form of fracking called LPG might be more efficient and profitable.
That currently unnamed company has asked GasFrac Energy Services to frack two Utica trial wells in Ohio using LPG, short for liquid petroleum gas. Founded in 2006 and based in Calgary, GasFrac is apparently the world’s only provider of LPG fracking and has used it about 1,200 times, mostly in western Canada and also in Texas and Colorado.
LPG uses a mixture of propane (and occasionally some butane) that’s pressurized to the consistency of a gel. Then, like water-based fracking, it’s injected through pipes at high pressure underground to release oil and gas by cracking open rocks using sand (or another proppant).
Unlike water, though, LPG naturally mixes with petroleum, so it returns to the surface with the oil or gas being extracted. And since LPG is electrically neutral and lacks much friction, it doesn't dissolve any salts, heavy metals or radioactive compounds — compared to water, in which these things return to the surface and make a typically toxic mixture even more so.
Fracking, of course, is enormously controversial, mostly because of concerns of potential risks to water supplies. LPG fracking eliminates an entire wastestream — the copious amounts of toxic “flowback” water that has to be reused, treated and discharged into waterways, or disposed of in deep injection wells, which have been linked to earthquakes in Ohio.
But why would companies using hydro-fracking — which has proven to be pretty profitable — be interested in using a niche technology like LPG?
“I think the results they’re getting [in the Utica] are sub-par, and they’re looking for an alternative,” said Kyle Ward, GasFrac’s spokesperson.
GasFrac argues that LPG, compared to hydro-fracking, is both more environmentally sustainable and economically efficient in the the long run — a claim that has drawn some skepticism.
Terry Engelder, the Penn State University geologist who’s been dubbed the “Godfather" of the Marcellus Shale for his calculations of the rock layer’s natural gas potential, says water is the "mechanically most efficient fluid for breaking apart rock.”
Anthony Ingraffea, a Cornell University engineer who spent 20 years researching fracking for Schlumberger, one of the largest fracking companies, said: "I'll give [GasFrac] credit that geochemically, it's much better to use a hydrocarbon [propane and butane] to stimulate a reservoir...But I'm not sure how well this technique will work in a high volume long lateral shale formation [like the Utica or Marcellus shales] because they haven't released proprietary data. That's still unknown."
Petroleum engineers in the 1960s and 1970s tried using propane fracking, but the potential for explosion — which is still a risk today, if better managed — left the technology uneconomical.
Last year, the petroleum giant Chevron used LPG to frack several natural gas wells in the Piceance Basin, home to several lucrative coal, oil and natural gas deposits in Colorado. The company’s annual report, while not mentioning GasFrac, noted that LPG "significantly increases production while minimizing water usage."
The company BlackBrush recently announced a two-year contract with GasFrac in Texas’ oil-rich Eagle Ford Shale.
Offering an explanation for the dearth of public data on GasFrac’s work for other companies, Robert Lestz, the company's chief tech officer, said, “Because our results our so superior to what people have done before, they're not interested in sharing those results.”
In Ohio, GasFrac’s spokesman said the company hopes to start the Utica wells by the end of the month.
It could be a proving ground for the technology. “It’s no secret we’re going to the Utica,” Zeke Zeringue, GasFrac’s CEO, said in a May conference call. “Obviously we hope that leads to an establishment of some sort of base of operations.”
While GasFrac has been keen to note in its recent marketing efforts that LPG uses no water, the technology’s profitability will ultimately determine its potential, said Michael Mazar, a financial analyst who follows the company for BMO Capital Markets.
"The environmental benefits are secondary."
CORRECTION: Because of an editor's error, Robert Lestz was incorrectly identified as GasFrac's founder in an earlier version of this story.
Anthony Brino is a Springfield, Illinois-based freelance writer whose work has appeared in The Allegheny Front, InsideClimate News and Illinois Statehouse News.