How Can We Cope with the Dirty Water from Fracking? [View all]

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http://www.scientificamerican.com/article.cfm?id=how-can-we-cope-with-the-dirty-water-from-fracking-for-natural-gas-and-oil


FRACKED WATER: Hydraulic fracturing requires millions of liters of water, and some way of coping with the dirty water that results.
Image: © David Biello

The nation's oil and gas wells produce at least nine billion liters of contaminated water per day, according to an Argonne National Laboratory report. And that is an underestimate of the amount of brine, fracking fluid and other contaminated water that flows back up a well along with the natural gas or oil, because it is based on incomplete data from state governments gathered in 2007.

The volume will only get larger, too: oil and gas producers use at least 7.5 million liters of water per well to fracture subterranean formations and release entrapped hydrocarbon fuels, a practice that has grown in the U.S. by at least 48 percent per year in the last five years, according to the Energy Information Administration. The rise is quickest in places such as the oil-bearing Bakken Formation in North Dakota or the natural gas-rich Marcellus Shale underlying parts of New York State, Pennsylvania, Ohio and West Virginia.

The problem is that the large volumes of water that flow back to the surface along with the oil or gas are laced with everything from naturally radioactive minerals to proprietary chemicals. And there are not a lot of cost-effective options for treating it, other than dumping it down a deep well. But as certain states that are experiencing drought begin to restrict industrial water usage, fossil-fuel companies are experimenting with traditional and untraditional water treatment chemistries and technologies to try to clean this dirty water—or limit its use in the first place.

Recycling is not enough
The first option is to reuse wastewater in whatever ways possible. For fracking, "to the extent possible, fracturing fluid is recovered and recycled for reuse in future fracturing operations," says Reid Porter, a spokesman for the American Petroleum Institute, an industry group. "Recycling of flow-back water reduces demand for freshwater and reduces the need for disposal of wastewater."