In New York State, no issue is more controversial than using hydraulic fracturing to extract natural gas from the Marcellus Shale formation. Here a well is drilled vertically, then horizontally into the layers of gas-rich shale. High pressure injection of water and fracking fluid fragments the shale, releasing the natural gas, which then flows back to the surface along with some water, known as flowback water.
Opponents of hydraulic fracking cite potential contamination of ground water by flowback waters, which contain methane and specialty compounds that help keep fractured rocks open. Disposing of flowback waters, which often contain barium, strontium, bromine, radium and salt, is problematic. Wastewater treatment plants are not designed to remove these materials, and contamination of surface waters would be unacceptable.
Interestingly, a new study has found that production of natural gas by hydraulic fracture techniques generates 35% less waste water than the production of the same amount of gas from conventional wells.
Brian Lutz of Kent State University calculates that for 1 million BTU of energy from natural gas, 13.4 liters of wastewater are generated from a conventional well and only 4.8 liters from a “fracked” well.
It would be nice not to use natural gas, which is a fossil fuel that contributes to warming of Earth’s atmosphere. But, natural gas is a cleaner fuel than coal, and appears less polluting to waters when it is obtained by fracking.
The solution will be proper regulation of natural gas extraction and an active program to convert our energy-intensive society from fossil fuels to non-polluting, renewable energy.
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Photo, taken on September 7, 2010, courtesy of Marcellus Protest via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY, with partial support from the Field Day Foundation.