A similar procedure is being fought against in Canada right now. I have read some of the studies done on it and to be honest right now I haven't made up my mind. There is a lot of suggestion that fracturing introduces pollutants into the ground water and some communities in Quebec launched complaints about it after their water had to be shut off due to fuel contents in the water. But the problems were corrected, or so they say.
We have been told for a long time that natural gas exploration is far less detrimental to the environment but there is growing evidence that it may be just as bad. In any case, I know that any number of studies saying it's not healthy will not stop the exploration. My uncle works for an oil company in the tar sands and I hear all about the mentality of the companies there. Seriously... you cannot meet a more greed-driven bunch. They will stop at nothing.