One month later, it has started. The leak, we pray, is going to be plugged. As Operation: TOP KILL KILL KILL is in effect, we can only hope BP isn't twiddling its thumbs while this happens there is a coast to clean:
The primary objective of the top kill process is to put heavy kill mud into the well so that it reduces the pressure and then the flow from the well. Once the kill mud is in the well and its shut down, then we follow up with cement to plug the leak.
For the top kill procedure we are designing equipment to pump the highest kill rate we can, irrespective of the flow rate of oil from the well, to force a downward flow of mud into the well. This, combined with the heavy drilling fluid is designed to eventually stop the flow. This has never been attempted at these depths. This is very complex and involves several complex procedures coming together.
This requires 50,000 barrels of mud, at the most, pumped down a 6 and 5/8 inch drill pipe through 3 inch hoses, then another set of hoses attached to the blowout preventer (BOP) and kill lines. Then there's the "junk shot" if necessary, basically shoots a bunch of random shit like golf balls and innertubes to stop the kill mud going through the BOP rather than down the well to cut off the flow.