it took 50 minutes of taking the heavy mud and putting in the sea water to underbalance the well. that means that if the cement job is failing, the hydrocarbons will start entering the well. ok. a little after that, nine minutes after that, we get this subtle increase. there is anomalous drill pipe pressure. the symptoms are starting to show up. on the sperry you sun data -- sperry sun data we do not know what transocean's driller was looking at. now we get the pumps are off and the drill pipe pressure is going up more steeply. the b.p. is open. the cement is the only barrier. hyd hydrocarbons are going to get up in the drill pipe. when they do above the b.o.p. there is nothing you can do to top that. when above the b.o.p. you can't stop the influx of hydrocarbons. 2138 the b.p. report calculates hydrocarbons are now in the riser. the b.p. is open. they are above the b.p. if you shut it down you still have a phaoemile of riser full hydrocarbons. imagine the volume. they are going to come out on the rig. even if the b.o.p. is shut at that point you probably are going to have a big

>> that's correct. >> so it's in no circumstances where you are most likely to severely underbalance the well in a the procedure? is that right? >> that's right. unless you've taken the kind of preemptive measures that we've discussed. >> there are regulations on deepwater drilling; right? >> yes, sir. >> do you know why they didn't account for this procedure? >> well, i think the regulation that i read is the regulation that would require the operator to can be if they were going to remove the hydrostatic overbalance, to do something that prove the well was safe to do that. the only practical, responsibility approach to doing that would be to do a negative test. to remove that hydrostatic pressure in a control system as was done with the b.o.p. closed to verify the well will hold back that external pressure that you are going to impose on it. >> let's assume, hypothetically, that the men on the rig that night at 8 p.m. had concluded this is a failed negative pressure test. what steps would the crew and men on the rig then have needed to take to diagnosis what the problem was and pot

increase the hydrostatic pressure below the surface cement plug to account for the additional underbalance from the displacement above? >> yes. in concept the density of the fluid below the plug could have been increased in the way that mr. bourgoyne has described earlier, although the deeper the plug is set, the less practical that becomes. >> okay. but in this case are you saying that bp could have chosen to increase the weight of the mud that was actually down here below the cement plug? >> yes, sir. >> what would have been the process by which bp would have had to have set that heavy weight cement or set that heavy weight mud? >> the most straightforward method would have probably have been to have run the drill string or the work string down to a depth just above the shoe track in order to circulate that heavy mud in place to fill that, that space in the well below that depth, below the 8367. >> and how long would it have taken to actually perform that procedure, to replace the lighter mud with this heavier weight mud? >> probably somewhere between one and two days based on what mr. l

>> up to the point where we start noting [unintelligible] we do agree the underbalance point happen before 9:00. there were different things happening during that time. >> bp said 852 p.m. 9 >> the -- one of the things she said, you have to get into the heads of the people on the red. we can only suppose what was going through our crew's head. when you look at the trend on a minute by minute basis with 20- 20 hindsight, you see trends that when the dollar took action, he saw a trend expected to happen. there were points when things were masked. the flow started coming in. it is -- coincidence is not your best friend sometimes. >> he did the necessary thing at that point to put the 14 pound will based mud back into the mud. system. it is unfortunate that at that point, it masked what was the biggest influence at that point. >> that is an interesting point. have you as transocean gibbon attention since this, you said it was a coincidence and the actions -- have you thought about any different ways of conducting these activities that could avoid an unfortunate coincidence which masked what wa

. >> so it's in no circumstances where you are most likely to severely underbalance the well in a the procedure? is that right? >> that's right. unless you've taken the kind of preemptive measures that we've discussed. >> there are regulations on deepwater drilling; right? >> yes, sir. >> do you know why they didn't account for this procedure? >> well, i think the regulation that i read is the regulation that would require the operator to can be if they were going to remove the hydrostatic overbalance, to do something that prove the well was safe to do that. the only practical, responsibility approach to doing that would be to do a negative test. to remove that hydrostatic pressure in a control system as was done with the b.o.p. closed to verify the well will hold back that external pressure that you are going to impose on it. >> let's assume, hypothetically, that the men on the rig that night at 8 p.m. had concluded this is a failed negative pressure test. what steps would the crew and men on the rig then have needed to take to diagnosis what the problem was and potentially remediate