Hydraulic fracturing, or "fracking," is the high pressure injection of water-based chemicals and sand into the ground. This process creates small fractures deep within the Earth to which natural gases and petroleum will inevitably disperse to and thereby be extracted from. Despite it's relatively recent inception, fracking currently yields approximately 60% of the Earth's oil/gas wells. However popular the process, hydraulic fracturing nevertheless has created a divide among the population with just as many critics as it has proponents.
Today, many government officials are establishing strategic zoning laws to appease opponents of fracking. These critics argue that the process poses serious risks such as the contamination of valuable ground water, the expulsion of chemicals to the Earth's surface, air pollution and the subsequent health effects caused by said risks.
Proponents of fracking urge the population to focus on the economic benefits of mining otherwise-unattainable oil and gas. They additionally argue that fracking is responsible for economic growth as well as increasing job opportunities. However, a study in 2012 by professors at the University of Wisconsin found that although fracking benefits overall income growth for a community, it has virtually no effect on employment.
I personally feel that, in terms of hydraulic fracturing, the potential risks of the means don't justify the end result. Phasing out fossil fuels altogether seems to be the safest and most reliable alternative to fracking.
Sources:
http://www.catskillmountainkeeper.org/our-programs/fracking/why-we-need-to-ban-fracking-and-adopt-a-renewable-energy-policy/
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1817691/
http://www.spe.org/jpt/print/archives/2010/12/10Hydraulic.pdf