EPA Administrator Lisa Jackson testified to Congress that EPA has not ONE confirmed case of fracking causing contamination or water pollution. See http://www.newsok.com/epa-chief-lisa-jackson-says-natural-gas-production-is-a-good-thing/article/3571012.
The EPA Administrator is using "fracking" to refer to the injection of fluids underground to break open shale and release gas. She is saying that no fluids have every come back to ground water and polluted it. She is not suggesting that spills or leaks at the surface have not caused problems or gas has not migrated from poor gas drilling.
Lisa Jackson's statement is completely consistent with my experience at the Pennsylvania Department of Environmental Protection.
The EPA favors strong regulation of the five stages of natural gas drilling to reduce impacts further. Lisa Jackson also recognizes that coal mining and oil production plus the combustion of coal and oil cause much more damage to health and the environment than natural gas.
As a result, Lisa Jackson herself said natural gas production is a good thing because it is already beginning to displace large amounts of coal and oil, thereby cutting total pollution to the environment.
Reason and facts have received support from Lisa Jackson and the EPA.