As usual, in-depth of analysis of current events is best found at a place we call “not the media”. This summary, titled Congressional Testimony and the Deepwater Horizon Oil Spill, at The Oil Drum;
What caused that catastrophic, sudden and violent failure? Was the well properly designed? Was the well properly cemented? Were there problems with the well casing? Were all appropriate tests run on the cement and casings? These are some of the critical questions that need to be answered in the coming weeks and months.
Over the past several days, some have suggested that the blowout preventers (or BOPs) used on this project were the cause of the accident. That simply makes no sense. A BOP is a large piece of equipment positioned on top of a wellhead to provide pressure control. As explained in more detail in the attachment to my testimony, BOPs are designed to quickly shut off the flow of oil or natural gas by squeezing, crushing or shearing the pipe in the event of a “kick” or “blowout” – a sudden, unexpected release of pressure from within the well that can occur during drilling.
The attention now being given to the BOPs in this case is somewhat ironic because at the time of the explosion, the drilling process was complete. The well had been sealed with casing and cement, and within a few days, the BOPs would have been removed. At this point, the well barriers – the cementing and the casing – were responsible for controlling any pressure from the reservoir.
Read on. Some of the industry discussion in the comments is just as interesting.
h/t Adrian
The BOP stuff seems like a deliberate distraction.
The attention this has been given by the usual suspects….
The entire matter seems just too convenient.
It seems, to me, 11 men died for a political point.
Congressmen talking blather because they don’t understand how the hardware works? How can this BE?!!!
I think the answer lies with BP and their past history of buying political absolution and using it to cover disastrous short cuts and dangerous cost cutting procedures. Was it Not BP that payed BO’s election fund a nice chunk of change?
I’d take any info from a peak oil site with a grain of salt.
Yes, they did, Bill.
http://www.google.ca/search?client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&channel=s&hl=en&source=hp&q=bp+donations+obama&meta=&btnG=Google+Search
I don’t know much about oil exploration, but I do have some insights into aviation and aviation accidents.
It is almost always the case in aviation accidents that it is a series of smaller actions that if they had happened by themselves or in a different sequence, would not have caused an accident. But when they happen in some unique sequence, the results are catastrophic.
I’m betting we will find out that is what happened here.
I’ll second Fred’s comment, from the point of view of the oil tanker business which I was formerly involved with.
Tanker disasters are rarely single point of failure. A series of low probability events, bad luck, bad judgement, and screwups have to line up for truly monumental disasters.
Well said, Fred.
Unfortunately over my career (I am now retired)I have had to analyze a number of military training incidents where death or injury resulted. These things did not just happen. When a series of errors or omissions took place, the odds that something nasty will not occur get higher and higher.
One wonders how many times accidents did not happen because someone did the right thing and broke the sequence of errors?
What would people in the oil industry know? It’s not like they are journalists or politicians or stuff.
Comments here are also good:
http://wattsupwiththat.com/2010/05/01/the-gulf-oil-rig-explosion-on-the-scene-photos/
Waterhouse, the link was recommended by a reader in the industry.
Forgive my ignorance on matters of oil drilling but if the casing is deemed unsatisfactory for any reason, would the best course of action be to repair the flaw or find new casing? Why wasn’t that done?
When modifications were made to the underwater panel why would BP not have the configurations and the documentation for those modifications in their hands? It took them almost a day to figure that the mods had even been done and that they were causing that function to be opening, not shutting the well.
How can that be? If I have modifications done to a vehicle, I want to know what they are and how they effect the performance. This sounds like a complete lie or complete incompetence.
Osumashi-To save money. Same reason as 99.9% of all blowouts. When bean counters call the shots, people die.
Almost every blowout in Alberta was caused by someone trying to save a few bucks. If you look closely, you’ll see an alarming pattern. Many of the incidents can be tied to a select few operators. They weigh the odds of an incident against the cost of prevention, and sometimes they lose the bet.
glacierman, sometimes as-builting (the documenting of shop or field changes) is not done properly for a variety of reasons.
It’s utterly disgraceful, dp. People get killed to save a few bucks.
The crucial error seems to have been the replacement of the mud in the riser with sea water prior to setting the final cement plug. It also seems clear this was a decision made by BP. But there’s another aspect to this error that has gone un-reported for the most part. The Wall Street Journal reported on 5/11 (see below) that BP secured approval from MMS for this irregular procedure. If this is true, then a large part, if not all, of the blame lies with the regulators – the ones, you know, who many seem to think are the solution to all risks (including offshore blowouts, second-hand smoke, fat in our diets, dog poop in public places, and bubble gum on the sidewalk). MMS approval of the procedure is not, of course, an aspect of this catastrophe the Lame Stream Media have any interest in pursuing. Hearings this week in the US Circus are supposed to focus on the role of the regulators. It will be interesting to see if there’s any mention of MMS having approved BP’s request to displace the mud with sea water.
Note, in the excerpt below, that both BP and MMS have declined to comment on the assertion that MMS pre-approved the irregular procedure. If it weren’t true, wouldn’t they have denied it?
Excerpt from WSJ:
A different account comes from Halliburton, a contractor in the drilling. This account is corroborated to some extent by Transocean, as well as by two workers on the drilling rig, The Wall Street Journal has determined.
This account describes a failure to place a cement plug within the well. The plug 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 two workers, in this case, that wasn’t done—drilling mud was removed before a final cement plug was placed in the well.
It is not clear why such a decision would have been made. Rig owner Transocean says that BP, as owner of the well that was just being completed, made key decisions on how to proceed. BP declined to comment on this account of the drilling procedures.
Tim Probert, Halliburton’s president of global business lines, plans to testify Tuesday that his company had finished an earlier step, cementing the casing, filling in the area between the pipe and the walls of the well; pressure tests showed the casing had been properly constructed, he will testify.
At this point it is common practice to pour wet cement down into the pipe. The wet cement, which is heavier than the drilling mud, sinks down through the drilling mud and then hardens into a plug thousands of feet down in the well.
The mud then is removed and displaced by seawater; the hardened cement plug holds back any underground gas.
In this case, a decision was made, shortly before the explosion, to perform the remaining tasks in reverse order, according to the expected Senate testimony of Mr. Probert, the Halliburton executive.
“We understand that the drilling contractor then proceeded to displace the riser with seawater prior to the planned placement of the final cement plug…,” Mr. Probert says in the prepared testimony, which was reviewed by The Wall Street Journal. The “riser” is part of the pipe running from the sea floor up to the drilling rig at the surface.
Lloyd Heinze, chairman of the petroleum engineering department at Texas Tech University, agrees that this is an unusual approach. “Normally, you would not evacuate the riser until you were done with the last plug at the sea floor,” he said in an interview.
A worker who was on the drilling rig said in an interview 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% less. Like BP, the MMS declined to comment on this account.
As the heavy mud was taken out and replaced with much lighter seawater, “that’s when the well came at us, basically,” said the worker, who was involved in the cementing process.
The worker’s account is corroborated by an email account sent by another person on the rig. He said that engineers wanted to flood the well with sea water before setting the final plug. As they were taking out the mud, the blowout began with a flood of drilling fluid being pushed out of the well, followed by a series of explosions.
Halliburton’s Mr. Probert’s prepared statement says: “Prior to the point in the well construction plan that the Halliburton personnel would have set the final cement plug, the catastrophic incident occurred. As a result, the final cement plug was never set.”
http://online.wsj.com/article/SB10001424052748704879704575236553480511416.html?mod=WSJ_hps_LEADNewsCollection
And Grand Isle looks like a ghost town.
Hope them boys saved for a rainy day, because they won’t get squat from Obama and FEMA, Obama is too busy workning on his Spanish, and FEMA is working on their We Don’t Support Republican Projects List.
The Ixtoc 1 deepwater well blowout in Mexico 1979 was blamed on a blow out preventer failure. It seems the pipe joints, the threaded section joints, do not crush as easily as the drill pipe itself.
BTW, the Mexico Ixtoc 1 well blowout spilled about 190 million gallons and took 9 months to bring under control …
Osumashi-It certainly isn’t exclusive to the oil and gas industry. Think Toyota, Union Carbide, Ford Pinto, Firestone Tires, and so on, and so on. I guarantee that in some board room, some bean counter overruled an engineer’s recommendations for proper blow out protection.
What effect did the sinking of the rig have on the BOP and the sealing of the well? What effect did all that water they used to put out an oil fire have on the boyancy of the rig?
Kate
Excellent link. The site and the technical comments are fascinating and the first meaty account that I’ve read.
While it’s been 15 years since I set foot on a rig (and never offshore) some things are universal.
The lack of bond logs, caliper runs, suspect pressure testing procedures, extreme depth, cementing practices, string configuration and lack of experience with this particular formation and field is a very interesting developing story.
On my bookmarks and kudos to Adrien for the tip.
Syncro
They know what happened now, one of the workers was on TV the other night (60 minutes I think) and told the whole story of incompetence and greed.
One of those chain reactions, a series of stupid mistakes and outright dangerous drilling.
The BOP was damaged and they knew it was.
Stuff BP president’s head into pipe to plug temporarily at least.