Hydraulic fracturing is a process used in nine out of 10 natural gas wells in the United States, where millions of gallons of water, sand and chemicals are pumped underground to break apart the rock and release the gas. It is also called fracking.
Scientists are worried that the chemicals used in fracking may pose a threat either underground or when waste fluids are handled and sometimes spilled on the surface. There is particular concern about fracking’s effect on drinking water.
As the spotlight shines more on fracking, it only becomes more controversial. Large and powerful oil and gas companies are literally staking their ground, and the practice has attracted the attention of government at all levels from local town councils to Washington. At the federal level, at the request of Congress, the U.S. Environmental Protection Agency is conducting a study to better understand any potential impacts of hydraulic fracturing on drinking water and ground water.
For ordinary citizens and residents of small, rural areas who are getting caught up in the controversy, the issue can be confusing. To assess fracking’s possible effects, you need to understand how it works. This graphic provides an explanation of the process.
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Click graphic to see a larger version
Graphic by Al Granberg and used here courtesy of ProPublica