Gasland has a giant hoax in it. Let's talk about the iconic scene in this "documentary": the lighting of the water coming out of the pipe. It is blamed on natural gas and the scene takes place in Pennsylvania.
The problem with the scene, beyond the allegations it was faked[1], is that methane is naturally occurring in the water supply of Pennsylvania[2]. In fact, long before fracking, George Washington and Thomas Paine did a bit of of an experiment involving it[3].
Add to this the fun fact the fracking is occurring at 6,000 and 10,000 feet and aquifers are about 500 feet down. Meaning that the gas released would still have to find a way up through a lot of rock.
There are some environmental concerns with fracking, but this isn't one of them.
Sure, that might explain the PA cases (I trust the oil and gas industries self-interested "explanation" for the phenomenon even less than I trust a muckraking documentary maker's, and a plausible — to me — alternative explanation is offered in the Wikipedia link).
https://en.wikipedia.org/wiki/Gasland