Don T., did you listen to the "60 Minutes" interview that I linked to up-thread?    It's with Mike Williams, who was a member of the Deepwater Horizon crew, and he barely escaped with his life when the explosion occurred. He describes what happened over the weeks leading up to the blowout, and the sequence in which these things happened.

If not, I suggest that you do.

Here's a link to the YouTube breakout of the interview:      60 Minutes interview with Mike Williams

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Ignoring the biases of the various news services, but paying close attention to reports and commentaries in the British press as well as others, plus discussing the matter with my aforementioned friend, who has worked on oil drilling rigs and who has been following this matter with great interest. Incidentally, he is not an American, he is from Sri Lanka, and is currently living in the U. S. He no longer works on oil rigs, he is now an ecologist, and he takes these matters quite seriously. The following has emerged:

The sequence of events begins with the first bore hole that was drilled by the Deepwater Horizon drilling crew. Up to this point, it was the deepest well ever drilled. 35,000 feet. And also, up to this point, the Deepwater Horizon crew had had an excellent safety record.

The job was actually on schedule according to the Deepwater Horizon crew. BP's estimated drilling time was 21 days. But this estimate was far too low. At this point, it had actually taken six weeks—42 days. BP was not happy with the fact that it was not meeting their estimate. But to do the job safely, it takes as long as it takes.

They issued orders to—as Mike Williams said in the 60 Minute interview—"Bump it up." There was an argument. The BP manager threatened that if they didn't speed up the drilling job, they would replace them with a crew that would.

So with great reluctance and considerable apprehension, the crew obeyed the BP manager's demands. And what they were afraid might happen did. The hole split open, the drilling mud leaked out, and they lost their drilling tools in the hole.

But—their ultimate fear, a blow-out, did not happen.

If the Deepwater Horizon crew had been allowed to complete the job without interference, there is every indication that nothing untoward would have happened. But because of this, they had to back off and start again, thus precipitating a whole new sequence of events.

They had to drill a new hole. It should be noted that at this point, some $25,000,000 had been spent with nothing gained. All because of trying to push the job too fast.

Now—with the drilling of the new hole:

The timeline according to Reuters:

April 20, 2010 - Explosion and fire on Transocean Ltd's drilling rig Deepwater Horizon licensed to BP Plc; 11 workers are killed. The rig was drilling in BP's Macondo project 42 miles (68 km) southeast of Venice, Louisiana, in 5,000 feet (1,525 metres) of water and 13,000 feet (4 km) under the seabed.

April 22 - The Deepwater Horizon rig, valued at more than $560 million, sinks and a 5-mile (8-km) oil slick forms.

April 25 - The well's blowout preventer fails.

BP's position is that something went wrong with the blow-out preventer installed at Deepwater Horizon. Perhaps it jammed against a tube-joint that it couldn't cut though, or there was something inside the tube that blocked it, like a piece of cement or other obstruction.

According to Mike Williams, what happened was that they had been ordered to test the blow-out preventer when a crewman accidentally moved a joystick, applying hundreds of thousands of pounds of force, apparently damaging the "annular," a ring of rubber. Pieces of rubber were found in the drilling fluid, which he said indicated damage to a crucial seal.

But a supervisor declared the find to be "not a big deal," and to press on regardless.

All the focus on the blowout preventer is a distraction from figuring out what went wrong with the well in the first place. Why was gas able to surge up from the well onto the platform, where it ignited into a fireball?

Shortly before the explosion that ended in the sinking the Deepwater Horizon rig, a critical series of events took place.

The concrete plug, made by Halliburton, is designed to prevent gas from escaping up the pipe to the surface. Before such a plug is placed, the job of keeping underground gas from coming up the pipe is done by heavy drilling fluid inside the well, commonly known as "mud." The plug is normally put in before the mud is removed. But according to the account of Halliburton, Transocean, and the Deepwater Horizon crew, in this case, that was not done. The drilling mud was removed before a final cement plug was placed in the well.

So—why was the mud removed before the final plug was in place?

If a decision had been made to reverse the normal sequence of events, the order could only have come from BP.

A worker who was on the drilling rig testified that Halliburton was getting ready to set a final cement plug at 8,000 feet below the rig when workers received other instructions. "Usually we set the cement plug at that point and let it set for six hours, then 'displace the well,'" said the worker, meaning "take out the mud."

According to this worker, BP asked permission from the federal Minerals Management Service to displace the mud before the final plugging operation had begun. The mud in the well weighed 14.3 pounds per gallon; it was displaced by seawater that weighed nearly 50 percent less. Like BP, the MMS has declined to comment on this account when testifying before the Senate committee.

As the heavy mud was taken out and replaced with much lighter seawater, "that's when the well came at us," said the worker, who was involved in the cementing process.

Neither the MMS nor BP are willing to comment. Their silence raises a host of questions. Suppose BP did order Transocean to displace the mud before Halliburton set the final plug in place. What would be the reason for that? And why wasn't a current MMS official testifying before the Senate committee, to explain exactly what the role of the regulator had been on the day in question?

Disavowing any direct knowledge of operational details on Deepwater Horizon, BP's McKay kept trying to gloss over what had happened by stressing the unprecedented nature of the entire disaster: "We've not dealt with a situation like this before," he kept repeating.

My friend, experienced with drilling rig procedure, explained the following to me:

Drilling mud is not "mud" at all. It is a man-made heavy and viscous slurry. It's purpose is to lubricate the bore hole for the drill bit and to act as a plug to prevent oil and gas from seeping up around the bit.

"If you remove the mud before you place the concrete plug, it's like popping the top off a bottle of Coca Cola after shaking the bottle. The concrete plug must be placed first or you are risking exactly the kind of disaster that took place in the Gulf of Mexico!"

Why did they want to remove the mud? "Drilling mud is expensive in and of itself. Companies like to salvage as much of it as they can so they can clean it and reuse it. Drilling mud amounts to a good 10% of the total cost of drilling a well, and it requires 'mud engineers' who know what they're doing. And they don't come cheap."

In my friend's opinion, BP management was cost-conscious to the point of micro-managing the drilling operation when they should have left the job to the people they had hired who knew what they were doing.

There's an old English expression:    Penny wise and pound foolish.

Don Firth