The so-called clean-up is really more an attempt to manage the damage. Contolled burns release oxidized products from the crude oil including carbon dioxide, sulfur dioxide, nitrogen oxides, etc. Booms and other collection/prevention devices/materials simply trap the crude oil and render it potentially possible to recover. The approach of the 'top-hat', etc. that BP is working on is a way of trying to capture the gusher crude via a 5000 ft long pipe. The use of dispersants does two things. First, it disperses the oil (breaks it up into smaller units) that potentially makes it easier for the lighter components to evaporate and/or enables microorganisms to have more ready access to the crude oil for consumption. The second thing is that dispersants are complex chemicals (largely derived from petroleum) and they themselves have certain toxicity.
The change in practices is also complicated. The deep water drilling that BP did is necessitated by the fact that much of the easy to find and produce oil in the world has been produced. New oil finds are, in general, going to be in ever more challenging locations necessitating technological advances to enable production. That's what we hear when BP says things like "this has never been done before at this depth", etc. Tightening up regulations and oversight might help. Corporate leadership with ever improving recognition of societal responsibility is a second. But, at the end of the day, this is always going to be some risk and this risk will remain evolving as the exploration and production end of the oil/gas business continues to have to push the envelop to get at new sources of hydrocarbon.
I believe that the empahsis must be on corporate leadership and accountability more than any other piece.
The size of the petroleum/gas business is so very large that it will be many many years before there is actually a substantive replacement alternative in effect.
