Natural Gas Drilling and Recyling Wastewater
Ian Urbina, New York Times, March 1, 2011
in a move hailed by industry as a major turning point, drilling companies are reusing and recycling the wastewater generated during the process of drilling for natural gas.
While wastewater reuse reduces freshwater demand, it does not fully eliminate environmental and health risks. Some methods can leave behind salts or sludge impacted with radioactive material and other contaminants.
In Pennsylvania, where the number of drilling permits for gas wells has jumped markedly in the last several years, in part because the state sits on a large underground gas formation known as the Marcellus Shale, such waste remains exempt from federal and state oversight, even when turned into salts and spread on roads.
More than 90 percent of well operators in Pennsylvania use hydrofracturing to get wells to produce, which uses large volumes of water. In the year and a half that ended in December 2010, well operators reported recycling at least 320 million gallons. Another 260 million gallons of wastewater were sent to plants that discharge their treated waste into rivers, out of a total of more than 680 million gallons of wastewater produced.
In addition to the potential ancillary impacts of salts, radionuclides, and other contaminants, there is currently no reliable tracking system of the wastewater's disposition.
Given that at least 50,000 new Marcellus wells are projected to be drilled in Pennsylvania over the next two decades, up from about 6,400 permitted now, the long-term environmental impacts and benefits of the drilling and disposal methods warrant further investigation.