The bottom line, is that fracking is no more dangerous than conventional methods of hydrocarbon extraction... if i drill and oil well in your back yard and the drill pipe bursts, your water is going to get mumped. In Gasland, every case they cited was an incident of improper drilling techniques, not fracking in and of itself. Fracking is done at a depth far below groundwater... think of it this way, if stuff at that depth could get in your drinking water, you'd already have natural gas in it.