Well, I haven’t seen any reference to the well flowing outside of the casing in the wellbore, and would welcome a link.
Either way, it isn’t just the quantity, it is the quality. the mud weight has to be enough to exert enough hydrostatic pressure to kill the well, regardless of whether the well is producing in an annular space or not. I am sure they will have a lot on hand.
Everyone, including BP, knows that the well is flowing outside the pipe. It has been talked about for days on the threads at http://www.theoildrum.com/node/6519#more .
Some of the folks posting there actually know what they are talking about.
That fact was recognized and discussed almost from the beginning here at FR.
http://www.freerepublic.com/focus/f-news/2498826/posts
Flow from the Macondo well is not travelling up the main well bore, BP operations boss Doug Suttles said Tuesday, a revelation that supports theories that a cement failure played a part in the blowout.
“We actually believe the flow path is between two strings of the casing and not up the main wellbore,” Suttles said.
Suttles said BP could not be certain of the flow path but diagnostic tests on the well seem to indicate the flow is not coming up main bore.