JIM LEHRER: This was another make-or-break day in the struggle against the oil spill in the Gulf of Mexico. BP crews launched a long-awaited operation to stop the oil at its source.
Monitor screens lit up with action at BP's command center in Houston this afternoon. Remote-controlled cameras a mile deep displayed multiple views as the top kill operation began. It came five weeks into the disaster, with a geyser of oil still gushing nonstop from the damaged wellhead.
BP's plan called for pumping heavy drilling fluid called mud into the blowout preventer that failed initially to stop the spill. Engineers hope the mud, followed by cement, would plug the well and stop the flow. It works on land, but it's never been tried at such ocean depths. BP gave the procedure a 60 percent to 70 percent chance of working, but some outside engineering experts warned, if it fails, it could make the problem much worse.
MAN: By imposing a high pressure, we may actually cause the flow rate to -- actually to increase, instead of decreasing.
JIM LEHRER: No wonder, then, that officials from President Obama on down were paying close attention. The president spoke in Fremont, California.
U.S. PRESIDENT BARACK OBAMA: If it's successful -- and there's no guarantees -- it should greatly reduce or eliminate the flow of oil now streaming into the Gulf from the seafloor. And, if it's not, there are other approaches that may be viable.
JIM LEHRER: And back in Washington...
MAN: Thank the secretary for coming as he departs.
JIM LEHRER: ... Secretary of the Interior Ken Salazar left a House hearing to monitor the preparations for top kill.
In the meantime, there was new focus on how the Deepwater Horizon oil rig exploded on April 20 and sank, losing the oil into the ocean. The Associated Press reported one worker on the rig told Coast Guard investigators BP was taking shortcuts.
And the chief mechanic on site on the day the rig blew spoke at a New Orleans hearing. Douglas Brown said he witnessed an argument between a BP official and drilling manages for Transocean, the rig's owner. He said the pressure to finish work was intense.
MAN: Prior to the event, were you aware of any type of concerns or pressures from either Transocean or BP personnel concerning completion of this particular drilling project?
DOUGLAS BROWN, chief mechanic, Deepwater Horizon: Yes.
MAN: When were those, please?
DOUGLAS BROWN: I didn't really hear anything verbal. It was just passed around via other people that this well was taking too long, and they were in a hurry to complete is it, so they can move on to the next.
JIM LEHRER: There were new calls for accountability at the House Natural Resources Committee hearing in Washington.
REP. NICK RAHALL, D-W.Va.: But I do think it is important to determine whether the Deepwater Horizon is the Wall Street of the ocean, privatizing profit, while the public bears the risk.
JIM LEHRER: The frustration from politicians on both sides was apparent. Arizona Republican Jeff Flake suggested government had learned nothing from past spills.
REP. JEFF FLAKE, R-Ariz.: We're still shoveling sand on the beach or doing some of the same things, washing off birds with, you know, handy-wipes or whatever else. And it just seems that we don't learn. Why aren't we, between spills, doing something that actually will inform us for the next spill?
KEN SALAZAR, U.S. interior secretary: There is a lot that has been learned. Maybe it's not everything that needs to be learned, and there will be a lot of lessons that will come from this particular response.
JIM LEHRER: BP said today it had paid out $36 million in damage claims. The current limit is $75 million, a ceiling that many, including New Jersey Democrat Rush Holt, are trying to modify.
REP. RUSH HOLT, D-N.J.: Would you support a legislative increase in the liability?
KEN SALAZAR: We are doing what we can within the limits of the executive branch to make sure they're held accountable. In changing the law, we are supportive.
JIM LEHRER: Tomorrow, the president is expected to call for tougher safety procedures and inspection regimes for offshore drilling.
We have more now on the top kill operation from Greg McCormack. He's the director of the Petroleum Extension Service at the University of Texas, Austin. For the record, the service partners with members of the gas and oil industry. He joins us tonight from Houston.
Greg McCormack, welcome.
GREG MCCORMACK, Petroleum Extension Service director, University of Texas at Austin: Thank you for inviting me.
JIM LEHRER: It's just after 6:00 Eastern time now, Mr. McCormack. And that means this operation, this top kill thing, has been under way now for four hours or so. Does the fact that it's still going after four hours mean anything?
GREG MCCORMACK: I don't think you can read anything into the fact that it -- the well is still flowing.
We would be able to kill this well a lot quicker if the blowout preventers were functioning properly. But with them not functioning properly, we're losing a lot of mud out through the blowout preventer.
JIM LEHRER: In other words, the mud is being blown out by the oil itself, right?
GREG MCCORMACK: That's correct. The pressure of the oil and gas flowing through the blowout preventer is going to carry some of the mud out into the riser.
JIM LEHRER: I assume -- have you been watching these live pictures from -- from the water, from the seabed?
GREG MCCORMACK: When I could -- when I could receive them, I have been watching them.
JIM LEHRER: What should we look for? A lot of people -- we have been running them live here online on the online "NewsHour." I have spent a lot of time watching it today. I didn't know what I was looking for. What should we be looking for?
GREG MCCORMACK: Eventually, we should be looking for a reduction in flow. That would mean that we're bringing the well under control and the top kill is working.
It's going to take a considerable period of time for that to happen. It's not an instantaneous kill. We have got to really fill all of the wellbore with this heavy-weight drilling fluid.
JIM LEHRER: And this heavy-weight drilling fluid, they call it mud, but it's not technically mud, is it? It's specially made for this kind of thing, right?
GREG MCCORMACK: It's specially made. It's a mixture of water, clay, to give it the -- the weight, and then some other chemicals to give it its property.
JIM LEHRER: And the idea is that the -- this thing they call mud, this liquid you were just talking about, is heavier than the oil itself, but there's a pressure collision. Is that correct? That's what's happening?
GREG MCCORMACK: That's what happening -- is happening.
Usually, when you're drilling, the weight of the mud keeps the oil and gas in the formation and stops it from flowing into the well until you need it. If you don't have a heavy enough weight, the pressure in the formation is going to allow the gas and oil to go into the wellbore. And I think that's what we saw here.
JIM LEHRER: But the fact that it hasn't -- that it is still flowing means only that not enough mud has gone in yet? Is that -- is that -- is that what you're saying?
GREG MCCORMACK: I think that's a correct statement.
We haven't put enough mud in to fill the total wellbore to create enough weight or pressure down where we need it at the reservoir.
JIM LEHRER: Now, the word going in, it might take at least two days of putting mud in there before we will know for sure. And you buy that?
GREG MCCORMACK: Well, I think it will take about two days for us to know if it's successful. We should see a reduction in flow after a period of time.
But we also have to remember we have to stabilize the well and make sure that it doesn't kick; in other words, the oil and gas flows back out of the reservoir and back into the well bore. So, I think that's why we need to wait the one or two days to make sure that this -- we have truly killed the well.
JIM LEHRER: What about the concern that was expressed that this -- this meeting of the two pressures could in fact damage the pipe itself and make things even worse? Are we over that, or is that still a possibility?
GREG MCCORMACK: Well, I think we have some restrictions, both of the blowout preventer and in the riser itself. And we want to make sure that we don't make those restrictions any less to impede the flow of the oil and gas there.
I don't know if we're past that point right now. I would think that if anything was going to happen, it would happen very, very early in the top kill operation.
JIM LEHRER: So, there is -- there is -- you could read at least that this -- up to this point, at least it hasn't gone -- that hasn't happened, that the pressure became so bad that it exploded again, exploded the pipe itself, right, or the...
GREG MCCORMACK: Well, I -- yes, I think you can make the statement that it hasn't destroyed any of the pipe.
JIM LEHRER: OK.
Now, the -- if this doesn't work, the word is from BP that they have got another dome ready to go. They have tried that one before, and it hasn't worked. What's going to be different this time, if it even comes to that?
GREG MCCORMACK: Well, I think they know what the problems with the dome was before.
When gas under pressure meets water, you form ice crystals. They're called hydrates. And those ice crystals like to join together and form great big snowballs. And those snowballs blocked off the containment vessel, so it couldn't allow the oil and gas to go to the surface.
They have learned from that. And what they're doing now in the containment vessels they're constructing now is having an ability to circulate warm author around the pipe and also to inject methanol in, which prevents the formation of these hydrates.
JIM LEHRER: Let me ask you, finally, you're an expert. You know what this is all about, and you know what's happened thus far. You know what is on the -- you just explained what is backup here. Do you, as a professional, have any sense of optimism that this thing is -- that this thing may suddenly or may soon be over?
GREG MCCORMACK: I'm cautiously optimistic, because I do want it over. I want it over for all the people of Louisiana and everyone that's been impacted by this.
JIM LEHRER: But the facts aren't there to make you any more than cautiously optimistic at this point, correct?
GREG MCCORMACK: That is correct, Jim.
JIM LEHRER: OK. All right.
Greg McCormack, thank you very much.
GREG MCCORMACK: Thank you.