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Just from a public-relations standpoint, hydraulic fracturing and severe drought are poor companions. Although fracing does not use a high percentage of consumed surface and groundwater (less than 1%, generally), it is still significant. Just in Texas, according to recent (mid-April) maps, there is exactly one little corner in southeast Texas adjacent to the Louisiana border that is NOT officially under drought conditions. And a large majority of the drought-smitten areas range from levels D2 (severe) to D4 (exceptional). The Eagle Ford region, where fracing has been increasing exponentially, is also suffering the most severe drought. In the Permian basin out in West Texas, where demand for frac water is greatest, the drought is almost as bad. It’s not a cozy or sustainable situation.
Smell those brackish waters. We’ve already discussed possible solutions in previous issues. Most companies are taking a two-pronged approach—using less water overall, and using a higher percentage of brackish water. Compared to its tasty, potable cousin, brackish groundwater is quite abundant, and lies in vast aquifers beneath much of the state and, in fact, under large areas of the world. It is estimated that Texas aquifers contain up to 880 trillion gallons of brackish water.
There are some disadvantages to using brackish water for fracing. For one thing, it is usually deeper than fresh water, and hence can be more expensive to produce. In addition to salt, other minerals are present that can cause scaling, or damage a well if they are not removed. More significantly, “brackish” is a generic term covering non-potable groundwater with many different chemical compositions, meaning that there is no single strategy for fracturing with it. Every region has its own unique chemistry and its own solutions.
Nevertheless, companies are moving forward. The Midland, Texas-based drilling company, Fasken Oil & Ranch, is pursuing a pilot program to fracture with a mix of fresh water and brackish water from the Santa Rosa aquifer. Apache has also been drilling in the Permian basin using the Santa Rosa water, which is less saline than some brackish waters (and far less saline than sea water), though it contains sulfates that must be removed. The company also utilizes the produced water brought to the surface during oil and gas production, which has a higher percentage of dissolved minerals. Apache mixes produced water with brackish water, and in some cases has been able to eliminate the usage of fresh water for fracing altogether.
Even a large-scale switch to brackish water in fracturing may not be the end of the issue. Western cities are increasingly turning their dry eyes to the brackish water aquifers to meet future water demand. Desalination and purification projects are moving forward, or are in the planning stages, in cities across the parched regions, which means that in the future, oil and gas drillers may find themselves in direct competition with these cities for even brackish water resources. The city of El Paso, Texas, currently has the largest inland municipal desalination facility in the world, with a capacity of 27.5 million gallons per day.
Why bother with water at all? Eliminating or greatly reducing the need for water in fracturing is another approach that has industry’s attention. One solution that is meandering its way south is fracturing with propane or butane gel, a process developed by GasFrac Energy Services of Canada. (For a detailed discussion of the technology, see World Oil, July 2011.) When LPG gel is used as the fracturing fluid, its ability to mix completely with natural gas, as well as its miscibility into crude oil, eliminates the need to handle flowback water. Biocides are not required. The gel has a constant viscosity and a much lower specific gravity than water, lowering shipping costs to the drillsite.
The company has used the process over 2,000 times in Canada and, increasingly, the U.S. About 100 frac jobs have been done in Texas, mostly in South Texas, along with “a couple of prototype fracs” in West Texas, according to a company press release.
It has been pointed out by critics that, while water is a nearly perfect incompressible liquid, LPG requires more pumping force to fracture a formation, and may not work as well at greater depths. There is also a greater up-front cost associated with LPG fracing, though anecdotal evidence suggests increased overall recovery may more than make up the difference.
Fracing with carbon dioxide has been done for years, but is mostly limited to areas that have CO2 pipelines, such as Wyoming. For CO2 to be made available in sufficient quantities that the technique could displace some water fracing, a steady supply of cheap carbon dioxide plus a major investment in a transportation infrastructure would be required. It has been suggested that the best way to achieve this goal is a price on CO2 emissions. As politically sticky as that might be, it could allow waterless fracing to grow hand-in-hand with carton capture, another area of technology with lots of growth potential. CO2 fracing has the same advantages as other waterless technologies. The CO2 can be used and recaptured, and when the well is finally shut in, the carbon dioxide stays sequestered.
Water wars. According to an International Food Policy Research Institute study, about half the world’s population will be at risk of “water stress” by 2050, if usage trends continue. As nations struggle to obtain and maintain critical freshwater supplies, water as an essential commodity will become more valuable, and conflict is inevitable. Wars have been fought over less. For the energy industries, though their water footprint is relatively small, it’s important to not be seen as part of the problem. At least, not this problem. 
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