well, lets see, if my car was leaking gas and destroying sea life in a daily widening plume, threatening potentially thousands of miles of coastline, making clean up workers sick, costing me over a billion in claims and growing, destroying the industry and livelihood of tens of thousands of people... and giving my company a name even more infamous than “Exxon Valdez”......
hmm, decisions, decisions
The ‘earlier’ efforts that BP used were to SLOW DOWN, and try to CONTAIN the leaking oil and gas. Neither the TOP HAT nor the INSERTION TUBE were meant to be complete SOLUTIONS to the spill. They were designed to limit the amount of oil/gas lost to the ocean.
The TOP KILL method has been planned from the very start. It took every second of time from then til now to get to the point where they are pumping ‘mud’ down the hole. Until the cement is pumped in, I would expect the ‘outflow’ of gas/oil/mud to continue (mostly mud, now).
The TOP HAT method was tried first, because it would not add any ‘stress’ to the wellhead, which is damaged, or to the foundation (ocean floor), which is apparently not very solid.
The TOP KILL method requires much more time to enact, and COULD cause more damage to the wellhead, and more leaks, or completely disrupt the integrity of the ocean floor around the wellhead. If it ‘blew’ the wellhead out of the ocean floor, say right where the faulty single cement plug between the liner and bore (annulus), then we would have new meaning for the word disaster.