Latest round in the fracking war
The EPA has a preliminary report indicating that hydralic fracking *has* contaminated well water sources of a community in Wyoming.
The article does note that the fracking environment there (depth of wells, geology, etc.) is different than that proposed in the northeast regarding the Marcellus Shale formation. Whether or not that means the Marcellus can safely be drilled without significant risk of contamination issues is still being hotly debated.
Also note from the article how the preliminary report is already being used as a political football to attack the EPA and the Obama Administration.