Hydraulic fracturing is the propagation of fractures in a rock layer caused by the presence of a pressurized fluid. Hydraulic fractures form naturally, as in the case of veins or dikes, and is one means by which gas and petroleum from source rocks may migrate to reservoir rocks. This process is used to release petroleum, natural gas (including shale gas, tight gas and coal seam gas), or other substances for extraction, via a technique called induced hydraulic fracturing, often shortened to fracking or hydrofracking.
New York State Assembly members Robert Castelli and Steve Katz call for a moratorium on hydraulic fracturing in the Croton Watershed in October 2010.
Fracking poses serious dangers to both human health and the environment. The three biggest problems with fracking are:
- · Fracking leaves behind a toxic sludge that companies and communities must find some way to manage. Safely disposing of the sludge created by fracking is an ongoing challenge.
- · Somewhere between 20 percent and 40 percent of the toxic chemicals used in the fracking process remain stranded underground where they can, and often do, contaminate drinking water, soil and other parts of the environment that support plant, animal and human life.
- · Methane from fracture wells can leak into groundwater, creating a serious risk of explosion and contaminating drinking water supplies so severely that some homeowners have been able to set fire to the mixture of water and gas coming out of their faucets.
Methane also can cause asphyxiation. There isn’t much research on the health effects of drinking water contaminated by methane, however, and the EPA doesn’t regulate methane as a contaminant in public water systems.
Because of the high demand for natural gas, the controversial process known as hydrofracking has created thousands of jobs. Yet environmentalists argue that long-term negative effects outweigh the short-term economical gain.
Ongoing concerns about the potential impact of hydraulic fracturing (fracking) on drinking water have pushed the U.S. Environmental Protection Agency (EPA) to investigate public concerns in light of the growing importance of natural gas in the clean energy future of the United States. On 23 June 2011, the EPA announced plans to conduct a draft study of the impact of hydraulic fracturing on drinking water by conducting case studies at seven U.S. sites.
Resources:
http://en.wikipedia.org/wiki/Hydraulic fracturing
http://www.oswegonian.com/news/5145/hydrofracking-the-controversy/
http://ehsjournal.org/