Yes, the petroleum industry can be trusted to develop a set of sufficient best practices to prevent environmental damage from hydraulic fracturing, because they have a critical public to impress that is concerned about the environment. Without government regulations, each company will take great care to impress the public that they are acting in the best interests of the environment.
I am double minded on this issue. This is because the government we have in office now will make sure that sanctions to limit hydraulic fracturing are in place. Those who oppose hydraulic fracturing would like it to stop immediately. But my leaning is that Exxon Mobil and the other companies can handle it.
Of course we can trust the petroleum industry to develop a set of sufficient best practices to prevent environmental damage from hydraulic fracturing. Oil companies will inevitably follow the will of the people by follow certain standards because if they do not act in a responsible way the people will hurt their business or even boycott.
The oil industry has not proven itself capable of developing technology to help if there is in fact a spill or something that damages the environment. Drilling technology is state of the art, but clean up technology is pretty much the same as it was in the 70s and 80s.
When considering the merits of this issue, one would have to decide that it is not worth the trouble, the costs, or the headaches involved. Each side must contend with the repercussions of such actions, and there is no reason that anyone should take such risks. These problems are completely avoidable.