Fracking seems like the dirty lovechild of mountaintop removal (e.g. for coal) and drilling for oil, a child that is just way crazier than what the genes of its parents would make you imagine.
Like drilling for oil, the natural gas that fracking tries to reach is stored underground, thousands of feet underground. But rather than having the pressure of the oil well pump oil to the surface (think of how the Macondo well spewed high-pressure oil into the Gulf), to get the natural gas, you have to fracture the rock structures in which the gas is trapped. This fracturing requires significant amounts of water, and of course, toxic chemicals (I mean, it just wouldn't be fun without toxic chemicals, right?!). This is a trait inherited from fracking's other parent, mountaintop removal. Just like mountaintop removal, we basically need to blow apart rock to release what it is we want. Mountaintop removal exposes coal, and fracking releases natural gas. What mountaintop removal is capable of doing, and has done to wonderful effect, is contaminate streams and on-land water sources (while at the same time potentially burying them altogether, drastically changing ecosystems). Fracking takes this a step further; fracking contaminates surface water and ground water and aquifers. The toxic brew of chemicals and water from the fracturing of rocks is either stored in containment ponds (basically a liquid landfill, actually just like the storage of sludge from mountaintop removal! Like parent, like child!), or released into streams and rivers. Of course, water treatment facilities are not equipped to treat water for the chemicals used in fracking.
Hmmm, so we're told that fracking is different, that it is safe, and that it is "better" for the environment. Well, it is hard for me to see the difference between what we've done in the past, and what we're doing now. Indeed, a toxic child is continuing and worsening a toxic legacy, just with a different face, a doe-eyed face. So in the end, while natural gas is "cleaner burning" than coal or oil, and releases more energy per unit mass of fuel, it still doesn't address the issue of what it is that is driving ecological degradation - a constant thirst for energy at any cost, a constant appetite to dominate nature, a willingness to treat air and water as dumping grounds. I would hope that people that are pressured into leasing their land for fracking can understand this. And I hope that my parents and their neighbours can fight the companies trying to get their land to frack it up.