On the surface, this sounds like great news ... well, as great as news can be in the face of an environmental catastrophe:

BP PLC said Monday that it will pay for all the cleanup costs from a massive oil spill in the Gulf of Mexico that could continue spewing crude for at least another week.

But what does that really mean?

Energy giant BP vowed Monday to pay "all necessary and appropriate clean-up costs" from the US oil pollution disaster in the Gulf of Mexico.

And what is necessary and appropriate? According to BP CEO Tony Hayward:

This wasn’t our accident. This was a drilling rig operated by another company. It was their people. Their systems. Their processes. We are responsible not for the accident, but we are responsible for the oil, and for dealing with it and cleaning the situation up ... We’re responsible for the oil and cleaning it. We are responsible to deal with the oil, contain it on the surface, and clean it up.

Does this mean that necessary and appropriate responsibility starts and stops with what's on the surface? Is BP trying to limit their liability from the real environmental and economic impact ... that which happens below the surface and on the shore?