A number of experts have already expressed the opinion that the original blow-out and the various top-down efforts BP has made so far to stop the SpillGate gusher may have weakened the well piping in one or more places below the sea floor. If the capping of the "Guillotined" riser caused any of these weak point to blow out, there would be absolutely no way of plugging them by top-down action.
This means that the gusher could continue, and there's no way to estimate the volume of oil this would release. It could easily be much more than is gushing out now. And this strikes me as a good reason to "Axe the Guillotine" and start trying to minimize the environmental pollution caused by the spilled oil while we wait for a relief well to by drilled.
Bringing in tankers and pumping up the oil as it boils to the surface above the well-head has worked to minimize the pollution from similar spills, but BP has claimed this won't work under the present circumstances because there are too many ships and oil rigs in the area where the oil is surfacing. This is true, but what they don't mention is that this equipment is there primarily to support efforts to cap the leak from the top down. Since these efforts have failed and the "Guillotine" seems to dangerous to try, there is now a good reason to clear out the ships and rigs and allow tankers to come in. The best to do this would be for the US government to take over direct control of the operation from the oil companies.
A third reason for an immediate government take-over is that most of the tankers would come from foreign countries, and U.S. diplomats would have to deal with the governments that sent them even if BP or other American oil companies were handling the technical details. And these technical procedures, unlike those involved in trying to stop an oil-well leak, would involve actions the EPA already has experience in taking.
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