What caused the Deepwater Horizon disaster?
Posted by aeberman on May 21, 2010 - 10:28am
Author’s Note: I am grateful to the many drilling and completion engineers that consulted with me on this post to arrive at plausible explanations and interpretations of what happened in the final hours on the semisubmersible drilling rig Deepwater Horizon in the Gulf of Mexico. The analysis that follows is based on these discussions as well as my own 32 years of experience as a geologist working in the oil and gas industry.
It is early in the process of discovering what really happened. Because of the gravity and potential impact of this disaster on the nation and my industry, however, I wanted to provide an early and more investigative perspective than much of what has appeared in the media to date. The risk, of course, is that more information will invalidate some of what follows. I, therefore, wish to clarify that this is a fact-based interpretation of what may have happened on the Deepwater Horizon on April 20, 2010 but, in the end, it is an interpretation. - Art Berman
The blowout and oil spill on the Deepwater Horizon in the Gulf of Mexico was caused by a flawed well plan that did not include enough cement between the 7-inch production casing and the 9 7/8-inch protection casing. The presumed blowout preventer (BOP) failure is an important but secondary issue. Although the resulting oil spill has potentially grave environmental implications, recent efforts to limit the flow with an insertion tube have apparently been effective. Continuous efforts to slow or stop the flow include drilling two nearby relief wells that may intersect the MC 252 wellbore within 60-90 days.
On April 20, 2010, the crew of the Deepwater Horizon was preparing to temporarily abandon BP’s “Macondo” discovery well in Mississippi Canyon (MC) Block 252 (Figure 1).
In a few hours, they would have been ready to move the drilling rig off location so that a completion rig could move on. At about 10:00 p.m., the rig unexpectedly began to shake and a loud surging noise was accompanied by natural gas, drilling mud and sea water that shot high above the floor of the drill ship. The gas exploded and the rig was engulfed in flames. A second explosion followed and the electricity went out. Eleven men died instantly and 115 others rushed to the lifeboats or jumped into the Gulf of Mexico. This all happened so fast that those who died probably had no time to understand what was happening. Two days later, the Deepwater Horizon sank to the bottom of the Gulf of Mexico, and oil has been spilling into the Gulf at rates of at least 5,000 barrels per day since then(there are 42 gallons in a barrel).
The MC 252 well is located in 5,067 ft of water about 50 miles from the coast of Louisiana. The total depth of the well was 18,360 ft below sea level (13,293 ft below the sea floor). This is not an unusually deep well nor was it drilled in exceptionally deep water compared to many other wells in the Gulf of Mexico. The Gulf drilling depth record was set earlier this year at more than 30,000 ft below the sea floor (The Oil Drum, January 18, 2010: http://www.theoildrum.com/node/6135#more), and the current water-depth record of 10,011 ft was set in 2003 (http://www.deepwater.com/fw/main/Home-1.html).
Much information has surfaced since the accident through congressional and Mineral Management Service (MMS) hearings, public statements from the companies involved and, on May 16, a feature report on CBS Television’s Sixty Minutes program. Most of this information comes from eye-witness accounts by people on or near the Deepwater Horizon at the time of the blowout.
I consider most of the publicly available accounts so far to be potential hearsay although they probably contain some good observations and elements of truth. I discount the value of the testimonials chiefly because none of these people were on the rig floor at the time of the blowout. In addition, the only people who have a comprehensive and fact-based understanding of the events leading to the accident are either sequestered by the companies involved or are dead.
Chronology of the Disaster
1. The well had reached a depth of 13,293 ft below the sea floor. The final string of production casing from the wellhead at the sea floor to total depth had been put in the hole, and cemented in place on April 19, 2010.
2. Only 51 barrels of cement were used according to the well plan. This was not sufficient to ensure a seal between the 7-inch production casing and the previously cemented 9 7/8-inch protection casing (Figure 2).
3. Mud had been lost to the reservoir while drilling the bottom portion of the well (this is called “lost circulation”). It usually indicates good reservoir quality, an interval of lower pressure or both, and can result in an enlarged wellbore or “washout”. The significance of this is that it might have been difficult to create a good cement seal between the casing and the formation. It also would have been impossible to ensure the effectiveness of the cement seal without running a cement-bond log, and this was not done.
4. The cement contained a nitrogen additive to make it lighter so that it would flow more easily and better fill the area between the casing and the lost circulation-washout zone. This also may have decreased its sealing effectiveness. Gas from the reservoir may have further diluted the viscosity of the cement.
5. While waiting approximately 20 hours for the cement to dry on April 20, the crew began displacing the drilling fluid (“mud”) in the wellbore and riser with sea water before setting a cement plug and moving off location. This mud was pumped into tanks at the surface, and then onto a platform supply vessel alongside the rig (whose captain gave testimony before an MMS hearing last week).
6. Sea water is much lighter than drilling mud so there was less downward force in the wellbore to balance the flow of gas from the reservoir. The drilling supervisors knew that there was gas in the drilling fluid because a gas flare can be seen in photos probably coming from a diverter line in the riser (Figure 3).
7. The chart of drilling parameters for the last two hours before the blowout suggests that the riser and upper 3,000 ft of the wellbore were fully displaced with seawater by 20:00 on April 20, and the crew was circulating the drilling fluid Beginning 10 minutes later, at 20:10, the mud pit volume began to increase probably because of gas influx (Figure 4). The volume increased so much, that the recorder re-zeroed four times. When the crew stopped pumping at 21:08, the mud pit volume decreased and this may have alleviated some concern about gas influx.
8. At 21:30, they stopped pumping again and circulated, but the pit volume continued to increase(Figure 5). Standpipe pressure increased and decreased twice between 21:30 and 21:42 (standpipe pressure generally reflects bottom hole pressure). This, along with a steady increase in mud pit volume, suggests that surges of gas were entering the drilling fluid from a gas column below the wellhead, and outside of the 7-inch production casing. Gas had probably channeled past the inadequate cement job near the bottom of the well and, by now, had reached the seals and pack-offs separating it from the riser at the sea floor.
9. At 21:47, the rate of standpipe pressure and mud pit volume went off scale, and water flow was measured at the surface. The blowout had begun.
Between 21:47 and 21:49 the gas behind the 7-inch production casing apparently overcame the wellhead seals and pack-offs that separated the wellbore from the riser. Almost instantaneously, the gas shot the water out of the riser and above the crown of the derrick. Then, the gas ignited and exploded.
Issues That Can and Cannot Be Addressed
There are many disturbing issues raised by the MC 252 well blowout. The Sixty Minutes report leaves the impression that there were clear indications of things that went wrong in the weeks leading up to the blowout. It further implies that BP and the other companies involved with the drilling operation ignored these problems in the interest of saving time and money.
I do not believe that there is sufficient and credible publicly available information to address those issues at this time. Based on the chronology presented above, it seems strange that so little was apparently done in the hour-and-forty minutes between the notable increase in mud pit volume and the blowout, except to stop pumping twice. At the same time, it is easy to see the warning signs now that we know the outcome, and we do not know what was done or discussed at the time--we only have recordings on a chart.
What can be addressed now is the larger issue that a flawed, risky well plan for the MC 252 well was approved by the MMS, and BP, Anadarko and Mitsui management. Similar or identical plans were undoubtedly approved and used by many operators on other wells drilled in the Gulf of Mexico. A plan that does not include enough cement to overlap the final and previous casing strings, and that does not require running a cement-bond log to ensure the integrity of the seal is a defective plan. The fact that there have not been blowouts on previous wells does not justify the approval and use of an unsafe plan.
Interior Secretary Salazar has announced a suspension of offshore drilling permits and an indefinite ban on new offshore drilling. This will have a profound economic impact on many thousands of rig and associated service jobs. The result will undoubtedly be new regulations. More regulation will accomplish little, however, if the underlying problem is a lack of critical thinking by the companies that drill oil and gas wells and the government agencies that oversee their activities.
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I thought that Mike Williams, who was interviewed on 60 Minutes, very eloquently summed up the situation:
http://www.cbsnews.com/stories/2010/05/16/60minutes/main6490197_page6.shtml
Proving once again the old industry adage I was weaned on-- "cut corners all you want, but never downhole".
A multi-hundred million dollar project over a two stage cement job, bottomhole liner hanger, or worse yet maybe 10 hours WOC time. Talk about the failure of the BOP all you want, everything meaningful in this business comes from an understanding of what happens in the formation and at its face.
Ignoring it will bite you in the ass every time.
FF
PS that little grill dulf or something like that was really on to something about the casing collapse I think... don't assume it was HOWCO's seal assembly-- it was tested.
BTW, if you haven't seen the extended interview with Williams on the 60 Minutes website, it's pretty riveting. He describes his rescuers rescuing Andrea, who jumped off the rig after Williams. Incidentally, does anyone know where the rescue boat came from? (I assume from the supply boat.) If there is a designated group of heroes in this situation, I think that it was the crew of this rescue boat. They went back to the burning rig to tow a liferaft away from the fire.
Here's one of many things I'm not clear about. If BP had not displaced the mud, and gone ahead and set the final plug, what are the chances that the will would have blown out anyway?
About you blowout question that is what I am trying to get out of what appears to be a really good completion man Dolph..... but we have communication issues... below is what I would like a GOM expert to comment on...
If the top plug was set and the pipe collapsed deep after this then the completion crew would have been dead men when they drilled out that plug... there would have been no way to see the pressure underneath the plug. If the well failed at the surface seal assembly, one would expect the choke and kill lines would be showing 13,000 psi above the plug when the completion rig moved on and thus there would be warning.
FF
That's a good point I have been pondering for a few days. Thanks for pointing it out.
FF,
I think that you see things as I do. Before I saw the wellbore schematic, I assumed (incorrectly) that the production string was hung somewhere in the 97/8 and that, if a plug had been set above, it would save this crew and kill the next when they drilled out the plug. As I wrote in my post, I believe the problem was the last cement job and the critical interface was the surface seal.
My drilling engineer friend says that he would have used a DV tool and port to put cement between the production casing and the 9 7/8 at the bridge plug ~3,000 ft. It's easy enough to say anything in hindsight, but he has 45 years of offshore experience and says this is just good sense, given the well design.
AEB
My accounting theory friend says you can never trust engineers because they are overly cautious and waste way too much money and time on worries over contingencies that never can happen in the first place according to generally accepted accounting principles.
Very few accountants are hurt or killed on drilling rigs.
The only ray of hope would have been that maybe somebody (a fresh team) would have made sure the BOP was operating before proceeding. Possible?
A horrible image to go along with your comment WT. Some 25 years ago or so a drill crew had to abandon the rig in very rough seas. For some reason a hand open the hatch on the capsule and it started taking on water so they bailed. A commercial fisherman was standing by and began pulling the hands out of the water. Very rough seas. One of the drill hands starting going under. The fishing hand didn't have a choice: he hooked the drowning hand in the shoulder with a gaff and pulled him on board. I don't recall a statement from the drilling hand but the fisherman said that it was such a horrible feeling that as soon as he rescued that hand he immediately vomited. After all these years I can remember the fisherman's interview like it was last week.
Just an opinion....but I think it hastened a process that was already in place. I don't think they would have gotten off this well without a disaster.
Think about it, if they had gone in to @ 8,000' and set the final cement plug in the 14.0 ppg mud, they would probably have pulled up above it, given it four hours or so to set up, then lowered the drill pipe to the plug until they saw it supporting some of the weight of the drill string on the weight indicator. That's how you check and make sure a plug has at least some integrity.
But then they HAVE to remove the riser to move the rig off location. That riser is @ 5,000 ft long and is @ 22" in diameter. That means it contains @ 2,350 bbls of synthetic oil based drilling mud. They either replace that mud with sea water or they release that 2,350 bbls of mud into the gulf.
What do you think they are going to do? They are going to displace the mud with sea water. Just would have bought a few hours time.
If the casing seals are prone to leaking, either way, the displacement from mud to sea water COULD provide the pressure release, hence the impetus, to bring the process to a rapid conclusion.
Hope this helps, and thanks for an excellent question.
Deeper
Westexas:
Here is a quote from "Rock Mechanics:Petroleum Applications" by Philippe A. Charlez "Recommendations for dealing with casing collapse in a compacting environment"
Quote:" At the present time, there is no solution which can prevent casing collapse in a highly compacting environment. However there are a number of precautions which can considerably delay (sometimes by several years) the phenomenon"
It may be when all is said and done that Mississipi Canyon 252 as well as being a new discovery may be a unique geologic environement. The author states that using Q-125 grade casing and double cemented liners are one approach to "delay the phenomenon".
I wonder what his opinion of using aerated cement would be. Although much discussion has been on the well design and casing schedule, most likely the casing points were the result of what was required to drill the well- not something they would have known when they spudded. A casing schedule for a wildcat is often "as necessary". The pore pressure profile would not have been known when they spudded.
Probably should have been a plug and abandon (not temporary) and a development well based on known pore pressure and appropriate casing schedule be drilled separately.
I'm just glad I made a decision to never return to offshore long time ago.
When i was a project engineer (not in drilling) the saying was "There's fast, there's cheap, and there's right, and you get to pick two."
hi west texas
am brand new at this [30 year offshore floater toolpusher and driller, now retired] can't navigate this thing yet so am just tagging allong on yours. hope you don't mind.
I have been on thes PC most of the last three days trying to find out the the ACTUAL ram components and thier order in the stack.
read the congressional testimony {boring] but I can count sworn testomoney from suposedly top oil men that mentions at least 6 different types of rams [many of which I have never heard of ie. what the heck is a "TEST RAM", you test all of them!
This BOP has only 3 ram cavities.
mitchblack
mitchblack111@yahoo.com
580 891 3389
Many thanks for this thorough assessment. One question - you say
How many wells have been drilled to this depth and deeper? I mean, is this a 1 in 10 failure, or 1 in 100, or ...? That bit of info would help put this disaster in better perspective.
clarification - I mean in the Gulf of Mexico, how many wells have been put in at this depth (not the entire world).
thanks
This Map of wells drilled in federal waters, Gulf of Mexico, says 50,686 wells, this file linked at Offshore oil and gas in the US Gulf of Mexico - Wikipedia, the free encyclopedia. EIA page on Distribution and Production of Oil and Gas Wells by State in the Fed GOM gives 3,286 producers in 2008.
Thanks - it seems from the map on the first link that Mississippi Canyon 252 is the farthest 5 percent or so from shore. However, there are at least 50-100 or more farther out.
dovey -- don't have a tally but there have been many dozens of wells drilled in Deep Water GOM. AFAIK this is the first DW spill of any significance out. IMHO the statistics don't really mean anything in this circumstances. It's not a card game: conduct business properly and safely and the odds of such a development are very low. Conduct your business in a sloppy and unsound manner and such a problem is almost certain to occur eventually. the only question is the magnitude and loss of life. In my 35 years I've never seen even one accident of any sort that was a result of "bad luck". Almost 100% of the time it was human error: a poor plan or a poor execution of the plan.
I was on the second deepest well drilled in the GOM a few years ago. But depth (either water depth or drill depth) isn't really the defining issue with regards to risk or difficulty. I've drilled wells onshore shallower than 12,000' that were much riskier and difficult than the typical DW well. Actually safety efforts and protocols are much tighter on DW wells if for no other reason than their costs. Someone has $500,000 spent on an onshore well might cut corners. But when you have over $200 million spent on one well and could produce $1 billion over time, you can imagine folks would not only be more careful but also willing to spend a little more to keep it that way.
That's what makes the BP accident so odd and inapplicable when it comes to statistics. There really should have been as close to a zero probability of a blow out as you can reach. They were well past the riskiest stages of drilling/completing in the DW GOM. And that fact alone may be the best explanation for how the accident came about. I gave a simple comparison a while back. When you slide behind the seat of your car in a parking lot do you immediately put your seat belt on for fear of someone running into you? I would guess that virtually no one considers that possibility. But many years ago I did read a story of a woman who was paralyzed from a broken neck resulting from her head being slammed against a steering wheel in just such an accident. Two teenagers were racing each other across the parking lot and one lost control. But even after hearing that story whose going to rush to slap their seat belt on after the get into the car?
OTOH I can assure you every operator in the GOM has new revised and very strict protocols for testing cement and displacing casings and risers. And that takes us to what APPEARS to be the base cause of the problem: it wasn't the cmt failing and the well coming in on them. There are procedures to handle those situation. IF the accounts are correct they weren't monitoring for flow back of drilling mud from the well as they were displacing. Monitoring well flow is THE primary safeguard in DW ops. I can promise you that such efforts were conducted 100's of time on just this one well while they were drilling. Back in January I drilled a deep well in the La. swamps. Every time we stopped the mud pumps, like when adding a section of new drill pipe, my company man would walk to the mud pit and observe flow back. There's usually a little flow back (30 seconds to a couple of minutes) even if the well is stable. He would do this even though the driller and the mud engineer were suppose to be watching also. That's how you take care of business properly. But it's easy to envision how no one was watching for the well flowing. One, it was cased and cmtd so it was "safe". Second, there always a big rush at the end of a well to offload equipment and personnel. After the BP incident there will never be another case of not watching for flow when displacing the riser ever again. There will be overkill by every operator out there. There will be multiple people and new system watching for it. But there will always be opportunity for other human errors and poor procedures IMHO.
I'm a big proponent of "never say never", but in this case Rockman is probably correct, given the finite life expectancy of the oil industry due to ... peak oil.
Doesn't peak oil ensure that hard oil, like deep water/deep wells become more commonplace? As the first world decreases its demand, the developing world will increase theirs. Especially countries like Norway aren't going to give up their cash cow cold turkey, and countries like Brazil aren't going to give up seeking their own cash cow, so to speak.
US gov't energy information people choose to believe that there is a peak of oil demand, not peak of oil supply. Since a collapse of world economy is a likely consequence of very high oil prices, it may happen their way. The decline of economic activity out pacing the decline of oil supply, in a race to the bottom. At some point there is no further financing for attempts to produce hard oil, and hard oil turns from plentiful to scarce. Here scarce means less plentiful in barrels per day the it had been in the recent past, not to mean supply is less than demand. People will be dropping out of the market to fast for supply to ever be less than demand.
But the developing world will have their plastics, tractors, and even if it were only mopeds for transportation, there are billions of them. They'll take up our slack, and perhaps then some.
The more they consume the sooner the collapse happens. You aren't addressing the issue that I am trying to raise. After peak the total rate (not merely per capita rate) of consumption and of production both go DOWN. If we don't find an alternative to oil, many people die of starvation on the way down. They do not buzz around on mopeds. Their aggregate compumption decreases because they are dying. When the music stops there will not be billions of them.
My comment is based on my expectation that at some point in the downward spiral, mankind will gets its act together and figure out an alternative life style that does not involve continued attempts to produce petroleum. And from that point forward there will surely be no more outer continental shelf drilling accidents.
The developing world might have plastics, but it won't be plastics from oil. They might have tractors, but the tractors won't run on petroleum sourced fuel. And we in the 'developed' world will have a similar restricted set of options.
Actually that is usually (although admittedly not always) the first thing I do when getting into my car. Perhaps because I had an accident 40 years ago in which I would have been dead if I hadn't had my seat belt on. I just do it on automatic tho, not because I fear someone running into me where I am parked.
However what you do personally to protect yourself is a far cry from what you do when the activities you are involved in have the potential for grave harm to a large number of people and the environment. If you are in a bioweapons lab every action with dangerous germs should we hope be done with an excess of caution. If you run a nuclear power plant every action should be done with an excess of caution. The more harm that can be done by a mistake the more caution called for. The parking lot seatbelt analogy doesn't work because the harm is to you alone, while drilling in the gulf the harm is to multiples of humans, economies, and an already fragile environment. If these things cannot be done with an excess of caution then they should not be done at all.
That's funny about the seat belt, because since I married an EMT 25 years ago, I've buckled before key insertion, out of fear :-)
Lately, I've been hitting the hazard flashers, in line with my longtime motorcycle theory that in order to avoid me, people have to be awake. I do LOTS of things to make people wake up, including two strips of truck bumper tape (hugely reflective) across my ECHO's bustle butt.
I listen to your story about your people checking other people and I nod my head. There is NOTHING like having your non-friends watching you to keep you awake.
These cozy team arrangements are hell on safety, because everyone excuses everyone else's sloppiness. Unfortunately as the old grumpy guys die off, to be replace by kids raised on "Greed is good!" we might see more GoM BOP disasters.
Good work. Best site, least crap.
Thanks Rock. I appreciate these comments. It does seem from the other links provided that maybe 100 or more wells at this water depth have been drilled in GOM ... so obviously it can be done. However, the deep water aspect adds an extra level of complexity, is less forgiving, and so is more likely to expose bad decisions.
From my understanding they were rushing at the end, and took their eye off the ball. Maybe because every minute out there costs a lot of money. With that incentive, there is always a possibility that people will rush.
Safety is a cultural thing. It comes down to good habits and thoughtful people. If BP is going to screw up like this, perhaps they shouldn't be involved in such a potentially destructive activity.
PS - I put on the seatbelt as a habit, without thinking. My boss used to poke fun at me for doing so when we drove from one side of the workplace to the other.
That's normal. I put on my seatbelt as part of the starting routine. That's simply the way I've learned it. It's the same reason I use my indicators on the driveway.
.
RockMan
Good comment about monitoring back flow. This is critical. The mud log posted is so obvious of an influx that I can't believe no one saw this. The only thing I can think of is that the increase in pit volume was occuring during the displacement which would be normal. If you are taking seawater suction from one place and taking mud returns to the mud system then you will have a continuous mud pit increase and detecting a kick is a little bit trickier. The best way to check would be to stop pumping seawater and observe the return flow. If this pit volume increase occured after getting seawater in and out with a "normal" circulation path, then its a sin and shame as there was ample warning. In that case ANY pit volume increase would trigger a flow check at the very least and a shut in and check for drill pipe pressure in my book. I just can't beleive on such a project that this type of oversight would have occured. Hopefully, we'll get the real story soon.
Boss was just reading in the paper that a partial BOP test had been run about 3 hrs. before the blowout....I thot that that was mentioned here previously, and a bunch of people said that that was not a typical time to run a test....Anybody got insight on that???
And this does sound like Rock's comment re: it might coulda been prevented if somebody was watching the pits more closely....
That well log looks an awful lot like an Epoch Well Logging Mud Log, back when I was a mudlogger I watched (in no particular order): total gas, flow, and pit volume, like a hawk. However, the operators always got us off the rig ASAP, usually within a day or two of TD. If the well was successful (like this one) and they were going to drill more holes in the area with that rig we wouldn't rig down and just left all of our gear in place--in addition to automated parameter logging, which is what I suspect we are looking at in this case.
Everybody who has ever worked offshore knows mudloggers aren't held in very high regard, but I have to think it would have served them well to keep somebody around, and pay attention to their sensor output.
I'm going to hazard a guess that when everything is processed, it's going to be the same thing as the Challenger disaster; the peons (and I include the engineers in this category) were overruled by the management.
Obviously, we are both speculating, but I concur 100%.
I have left behind my petroleum geology days and now work in safety, where a common phrase is "good enough is good enough--until it isn't."
I get the feeling that BP had concluded that they had historically been a bit over-cautious with well construction in the past and were working on creating a new efficiency.
Project management is all about on time, on budget. Look at BP's compensation & bonus policies for the managers to see why this happenned. The managers who got promoted woud be the people who always came in on time, on budget (under is better).
paddle -- I,for one, hold mud loggers in high regards. Hands working for me either give the mud loggers their due or they get run off. Tolerating stupidity is a good way to insure problems. OTOH I've run off my share of mud loggers: got respect for the good ones and no patience with the bad ones.
Yeah, I suppose I should've qualified that! I usually managed to get along with the folks out there--professionally as well as personally--but only after I'd been out for a week or two and had proven myself to some extent. I did work for a company that tried to only hire loggers with a four year geo degree, so we were sort of "the cream of the crop."
After a year or so, I hopped over to an outfit and did MWD work and got to see the spectrum of mudloggers that were out there; I'd say a diplomatic way to put it would be that quality was "uneven!"
I can say this, while I took my share of chops busting, in a few dozen wells I was never run off.
The data presented is from the Sperry Insite program and not all of the variables were shown. This data was transmitted by satellite to whatever Real Time Operations Center that BP had. There would have been operators there. Most significantly absent in my opinion is the pump strokes. Mudloggers would have been released probably when they reached TD and after the liner was run. They may have been onboard however, I guess we will find out eventually.
I gave up on offshore long time ago so I'm not sure about when they would have been normally been released at the present time, but I can find out.
As an old hand once told me.."Don't blame you, Don't blame me...blame the mudlogger behind the tree!"
Thanks for the excellent summary. A couple of thoughts
1.) What is the most common result of an unsafe act? Answer: Nothing, in retrospect we inadvertently do things which are unsafe all the time and nothing happens. Unfortunately it is only after the accident things are recognized having been unsafe.
2.) People do not get hurt doing things which they
believe
are dangerous. It is those things which are dangerous which we did not believe to be so that get us.
Throughout my careers in both the Navy and the Oilfield, how many times have I looked and said, "There, but for the grace of God, go I"
It is a risky business. I have been on blow outs and other accidents. Seen wireline cables part at the rig floor, seen equipment fail in un-expected ways. It takes these types of incidents to remind us that it is risky, and raise our awareness from cognition to belief.
Be safe,
ej
estamos jodidos -
Words of wisdom, to be sure!
I happen to have spent many years conducting environmental and health & safety audits in a variety of industries. After a while, you start seeing certain patterns.
In reviewing past accidents and injuries, it has always struck me that most serious events are not the result of some major design flaw or equipment failure, but rather the right combination of a bunch of stupid little things coming together at the wrong time.
As I keep telling my grown son: watch out for the little things, as they are ones that are likely to do you dirty.
Being an industrial safety officer is a losing game. You will never know about the catastrophe your actions prevented, but you will be continually blamed for wasting time and money in doing so. And of course you will be blamed when something does go wrong. It's a lose-lose proposition.
estamos, since you know it is a risky business, why did BP assert that it was not?
Twelve months ago BP dismissed the possibility that a catastrophic accident could happen at its offshore rig Deepwater Horizon, it emerged yesterday. An exploration plan and environmental impact analysis for the well, produced by the company in 2009, concluded that it was virtually impossible for there to be a giant crude oil spill from it...Yet BP's plan for the Deepwater Horizon well, filed with the federal Minerals Management Service, repeatedly said that it was "unlikely that an accidental surface or subsurface oil spill would occur from the proposed activities". The company conceded that a spill would have an impact on beaches, wildlife refuges and wilderness areas, but argued that "due to the distance to shore [48 miles] and the response capabilities that would be implemented, no significant adverse impacts are expected".
http://www.guardian.co.uk/environment/2010/may/02/bp-oil-spill-costs-impact
What you have seen BP has seen or knows about. So to assert in its plan filed with MMS that it was unlikely, is in fact a lie is is not. If they lied then you can be double sure they are lying now. Trouble is that people begin to believe their own lies and cut corners because they have already determined that an accident is unlikely.
If we go to a Dr. for major surgery we would like to know his track record for that surgery. We know an accident can happen no matter how carefully the Dr. is vetted, a knife slip perhaps, but we want a Surgeon who is declared competent by the AMA, follows accepted procedures, doesn't cut corners to get to the next surgery, and has a record of success with the surgery. Time to hang up BP's shingle. If they were a Dr. they would have lost their licences to operate after the TX refinery fire. Who of us would want a surgeon to operate on us who has been convicted of a felony in relation to a previous surgery.
Art, you state that the cause is that there was not enough cement between the 9 and 7/8's and 7 inch casings. Is this based on the fact that it failed to hold the pressure, or is there an amount of cement, say yards per inch of casing length, that is known as a standard and not applied? Thanks for your reply.
Not an oil expert by far, but I have read everything, including this last well thought out piece. For me, these are the areas to focus on:
1) MMS approved flawed plans for the project.
2) The Schlumberger crew was there to do the definitive wire tests on the cement job.....they were told to stand down by the BP company man.
The details of how #2 occurred are going to at the heart of any criminal trial IMO.
Um...another version of SLB rumor....From the other discussion mentioned downthread.
http://www.flickr.com/photos/uscgd8/4551846015/page9/
About the Morgan City rumor--I call it that because smb from Morgan City told me this about two weeks ago. Apparently in the day of the accident the Schlumberger people were there to do a CBL. The well had been acting up already that day, and they were chasing a phantom pressure anomaly all over the place (remember also that a couple of the pressure tests failed before they got one that supposedly passed). Schlumberger wanted them to keep the mud in the well for them to do the CBL, but the BP man wanted to evacuate and plug. Apparently there was a tiff when the BP man said he didn't want a CBL (it would be difficult to know WTH they were doing out there if they weren't anticipating running one) and the Schlumberger people pulled their crew, got in their helicopter and took off. That evening the rig blew up.
Please send me an eMail
alan_drake at juno dott conn (convert to standard form).
Best Hopes for Finding the Truth,
Alan
That's a copy of the post made 2 days ago by user IntellectuNeck on Flickr which tollertwins just spotted. You might be able to get in touch with IntellectuNeck on Flickr though.
I searched Flickr for "IntellectuNeck" and got nothing. Could you provide a link or at least a way to find this post ?
Thanks,
Alan
I searched Flickr for "IntellectuNeck" and got nothing. Could you provide a link or at least a way to find this post ?
http://www.flickr.com/photos/uscgd8/4551846015/page9/#comment72157624103...
Rockman addressed this here: http://www.theoildrum.com/node/6462#comment-622744
Thanks for your reply. Based on Rockman's comment on your link above, it seems it is just add enough cement to fill a known volume of displaced drilled material. Which would get tricky with a washout of material from the hole. So the CBL seems even more imperative, funny it isn't required in such cases. Probably there must be some indication within the quantities of mud returned to the surface, but it still appears to be a lot of seat of the pants guesswork.
'funnu it is not required' ? let's not forget 11 hard working people died, nothing funny here!
Dolph-
What is the current "accepted" wait time for a CBL?
Thanks
FF
Most give it 24 hours but I prefer 48. I have seen bad CBL's that became 'good' when repeated years later.
For sure they should have waited longer testing the casing and not start already after 10 hours. A 2,500 psi pressure test could have been done when they bumped the top plug straight away!
I don't think he meant "funny, ha ha". Due to the imprecise nature of our language, funny can mean "odd" or "strange" as well. You could re-write it as "It's strange that it is not required". That's how I read it, at least.
It's not funny in that sense at all. I meant meant strange, or WTF, can't believe it, etc. But also from that thread of Rockman's, Amaco's ~1980 study shows doing it right the first time is better insurance than a CBL. Esp. with BP buying Amaco, you can bet that study will resurface. But that assumes they did it right the first time, which obviously they didn't. I wonder if the study has been repeated.
At least during the intitial drilling phaeses, washout or caving is sometimes quantified by pumping a "pill." That means a few pounds of calcium carbide is placed in the drill string at the rig floor, the string is re-connected and circulation restarted. the Calcium Carbide releases acetylene in contact with water, and acetylene can be detected by the mudlogger's gas chromatograph and will not be mistaken as normal reservoir gas. When this is done, expected hole volume is calculated and divided by pump stroke volume, givining an expected stroke count until the acetylene shows up. If a greater number of strokes is required to move the acetylene from "surface-to-bottom-back-to-surface" you can conclude that the hole has caved and expanded in volume.
This can tell you you will need more cement (as well as letting you know your calibration from bottoms up is a bit less certain) but, while this is fairly common, it isn't done automatically.
Having been once a wireline engineer with SLB I find it hard to believe that they would have tried to save some money by not running a cement bond log. This would imply that this sort of cost cutting attitude must have been going on for some time. I have been on far less spectacular exploration wells where every thing on our racks was run into the hole. Now we have an ultra-deep where they skip obtaining valuable information about the integrity of the well construction. AMAZING !!!!
The deeper we went with the logging tools the more we charged, reason for my guessing that it was cost that was an issue. In Hostile environment, we added extra charges. Not sure any more what additional charges in such a logging operation would make the logs SEEM expensive to BP to make them think that skipping it was OK, but cost seems to me to have been their reason.
One possible factor in the accident that I haven't seen mentioned was the presence on the rig of the officials from BP for the safety award/celebration. In my experience the presence of such a group can add tension and/or pressure to what otherwise might be a more 'relaxed' normal work flow. It may seem a little silly, but I have seen it happen more than once.
[edit] another possibility is that one or more pairs of eyes that normally would have been occupied with overseeing the finishing up of the work was instead occupied entertaining the guests.
I also had wireline experience. I don't think they would have bypassed the CBL to save on cost of the logs, but rather cost of rig time. I also believe that while SLB had a crew on until shortly before the mishap, I understood it to be a crew to log the open hole section rather than cased hole. In the US/GOM, SLB normally, atleast or used to, segregate the services by OH/CH so the crew on site may not necessarily have had the equipment for CBLs. Why they would have remained onboard during cementing is a mystery. Again, I don't know the details, but just how things used to be. Could be different now.
ej
Doug,
The statement that there was not enough cement is based on a volume calculation from the 51 barrels (cited by Halliburton in House hearings) made by an unnamed company with all of the credentials. It is also based on the well schematic diagrams presented in the House hearings from which the schematics that I show are modified.
Good question.
Art
Fantastic post. I really appreciate how you did not try to allocate blame to individuals on or off the rig. Eventually, after an extensive investigation, one or more people may be found directly responsible. For now, it is far too early to tell the human error side of the story.
By focusing on the mechanics of the blowout and the system in place that may have allowed for a faulty well plan, your post has much more impact.
I hope a nation that reminds itself, from time to time, to "Support Your Troops" also takes a moment to reflect on the incredible work, and the occasional sacrifice, of those people that produce and deliver our energy. To all those serving our the energy industry: Thank You!
Gave you all a passing mention on my little blog, in a view from the ordinary guy.
http://www.mentalcrumble.com/
It is my understanding that the casing string is a full string of 7in by 9 7/8. The 51 bbls of cmt was designed to back up the 7 in and did not overlap into the 9 7/8 by 11 7/8 annulus or even cover the entire 7 in by open hole annulus. Haven't seen anything that said the cmt inside the 7in was tested with weight and pressure. Also don't understand why the seawater displacement was so hurriedly done without setting a cmt top plug and testing that before displacing.
One possiblity driller: last January I had to re-enter a well that had OBM (oil based mud) left in the csg. No problem...just circ it out and set my whipstock..right? Two weeks and $500,000 later finAly got the whip set. Could not beleive how the OBM set up on the csg walls along with a bunch of metal. maybe that's what they were trying to avoid: displace so they didn't leave OBM below the top plug.
So many factors are different, granted. I do find it odd no one recalls Ixtoc I to use for comparison. Instead, Exxon Valdez is invoked; a poor comparison.
Ixtoc was a shallow water well (the BOP and wellhead could be accessed by divers) that experienced a complete loss of control at the time of the blowout. Despite the size of the spill a relatively small portion of the oil made it to US shores because of the well location (600 mi from Texas) and ocean currents in the area. It was a 'foreign' well.
The Valdez was a surface spill near shore and the oil washed up rather quickly.
Each event is unique to some extent and direct comparisons are not straight forward.
We should look at it more in detail: (everything below assumes a 13.7 ppg equivalent reservoir pressure)
The differential pressure is what counts, meaning, if the cement was leaking:
There could have been 13,000 psi reservoir pressure in the 16" x [9-7/8" x 7"] annulus with 2,240 psi inside the [9-7/8" x 7"] casing, filled with seawater, giving a differential of 10,760 psi which is too high in design terms and for sure in real life, if the 9-7/8" 62.8 HCQ-125 casing collapse pressure is 13,840 psi theoretically, but (13,840 - 30%) = 9,690 psi including design & safety factor.
Now for the 16" if we assume the strongest casing, the theoretical burst pressure is 10,900 psi.
For design we subtract again 30% leaving 7,630 psi.
In the annulus 16" x 22" is filled fresh water of 8.345 ppg for a minimum.
This gives at 5,067' wellhead depth x 0.052 x 8.345 = 2,200 psi.
Differential over the 16" casing is 13,000 - 2,200 psi = 10,800 psi which is far too much.
So if the 16" would burst the 13,000 psi pressure could get to the wellhead seals of the 22" & 28" causing them to burst, since they have a much lower rating normally, ending-up in a blow-out at wellhead.
Another senario could have been a blow-out via the 18" liner top to the 22" shoe and then up to surface.
Even if the expected reservoir pressure was much lower or even zero, still the whole design of the casing programme is wrong.
- first of all it seems they never heard of 'buckling' since they leave a heavy casing string 9-7/8" 62.8 ppf x 7" 41 ppf hanging free over 12,100 ft on the casing hanger???
- What do they think will happen when they run completion and start flowing the well and is warming-up?
- if you have so many strings/liners,each with minimum cement behind it, for sure you will do a CBL at the end to verify you have isolated everything
- why is only the upper prt cemented back into the previous casings and the rest not, weak zones which cannot support cement column? never heard of external casing packers or stage cementing, specially for the production casing?
- the reservoir is probably drilled in 8-1/2", if they would have had a 13,000 psi kick, even with the BOP functioning properly and ultra heavy casing everywhere, how where they going to control this? Certainly not with the 7,500 psi max. WP mud pumps, remaining the Halliburton HP unit (probably 15K rated) but at which flow rate??? Pissing against the wind!
This design is so wrong I almost cannot believe that the data provided by Halliburton are correct.
Now next is why to have a 9-7/8" casing on the top? Of course you will answer: to allow to run a 7" completion string! Why they would like to run a 7" completion? Because there is plenty oil. 5,000 barrel/day can be easily produced through a 3-1/2" completion string. Now if there is plenty oil they could have invested a little bit more money in the well isn't it?
VERY IMPORTANT REMARK: THEY DID NOT WAIT 20 HOURS TO TEST THE CEMENT - in the drilling report one can read that already at 10h30 AM [this is only 10 hours after completion of the cement job which was at 00h35 as per the same report] they closed the BOP and pressured-up to 2,500 psi through the kill line in order to test the casing for 30 minutes, this test finished at midday. Now when cement is setting it is not smart to put this on since the casing is 'ballooning', when the pressure is bled-off the casing will come-back to its original position and micro cracks may remain, allowing gas to migrate through them.
Could you give me the rationale for the tapered production csg of 9 7/8" to 7"?
And why hang it off the csg hanger at the top of the well?
And could they not have drilled to TD with 9 7/8"?
As a geologist I've worked Hibernia, Sable Island, Shallow Panuke and Deep Panuke, but never GOM.
Great post. I want to look at this bit of your post:
>- the reservoir is probably drilled in 8-1/2", if they would have had a 13,000 psi kick, even with the BOP functioning properly and ultra heavy casing everywhere, how where they going to control this? Certainly not with the 7,500 psi max. WP mud pumps, remaining the Halliburton HP unit (probably 15K rated) but at which flow rate??? Pissing against the wind!
Remember the pressure increase due to gravity as you go down the pipe. With 18000 feet of mud, they could hold it but it is so tenuous. It does not seem safe to "count" the extra pressure at the sea floor due to a standpipe of high density mud...is that how they were getting it to work?
There is an ongoing discussion of the technical aspects of the well hardware and implementation here for those who might not have seen it:
http://www.flickr.com/photos/uscgd8/4551846015/page9/
would buckling really be a problem ? 7" casing couplings would have a maximun of about 3" clearance inside the 11 7/8". 7" casing is bent from vertical to horizontal in about 500' for hz drilling all the time. i'm just asking.
or are you concerned with buckling of the 9 5/8" ?
the id of 9 5/8 62.8 ppf is about 8.34 inches. or is the 9 5/8 liner at the bottom lighter than 62.8 ppf ?
i dont get the tapered casing design either. wondering if they were planning to run a huge submersible ?
elwoodelmore
The casing is 9 7/8, I was surprised to find it in the book ID=8 5/8"
If they were planning to use it as a production well, the tapered string could have allowed 6 5/8" production tubing to be used, which is all the go in big bore wells, full bore Sub Surface Safety Valves (SSSV)is another reason to go with a tapered string, though for 6 5/8 tubing it would require a 10 3/4 casing and this size had already been used.
Has BP said they were going to use it as production well, or was the idea to come back to it, to do a production test? The reason I ask is, I believe but can't confirm that production well heads are differant to throw away wells in the fact that they have the ablity to read annulus pressures once the christmas tree is attached. From what I can gather this was a pure exploration well.
To rig up for production testing is a major task, and the DW Horizon was a straight drilling. Meanwhile the Enterprise drill ship is on contract for BP and is equiped to collect produced oil during production test. Is this not a more likely plan? What are the flareing rules in the Gulf, I hear they are very strick.
While I am the subject of flares. The photo at the top pointing to a flare, I think you will find that it is the open diverter. It would have been opened either to dump the returning water after displacing the riser, or opened when the gas was expanding up the riser.
i see that now.
i havent read where bp says that. only the report of what dr. bea or somebody from berkley said stating they were in the process of converting the well to production.
someone on here asked about dst's. does the mms allow dst's offshore ?
Great Post
These are theoretical volumes do we know if a caliper waqs run before the liner? I understand from a previous thread that foamed cement is hard to pick up from a cement bond log. these have never beeb totally reliable in my experience anyway so running one would not necessarily have prevented events happening, How could the design have been so inadequate?
Folks:
First of all, may I please thank you for providing a clear understanding of what is happening with both the incident itself and the follow-up. The information here is much more substantive than what I see in the media.
There is one thing that I need help with, though. And I might not be in the correct forum for asking this; please refer me to wherever would be a better place if this is not it.
I am having trouble comprehending the discussion on the pressures. Gail and HeadingOut (I hope I have the names right) cite some pressure values that I am having trouble visualizing. I think it was Gail who mentioned something about the well pressure of 18,000 psi and the water pressure of 8,000 psi, meaning a difference of 10,000 psi, which is the pressure of the oil in the pipe.
What my issue it (and I am not disputing your figures), is just what is 10,000 psi, or 18,000 psi.
I have an air compressor in my studio that maintains a pressure of about 120 psi. When I open the outlet (which is about 1/4 inch in diameter), and stand about 12 feet from the opening, I can just barely feel the air rushing toward me.
What would happen if that were, say, 10,000 psi (the difference between the well and water pressure at the floor (where the BOP) is?
Another question, at 10,000 psi, and a 1/4 inch hole in the pipe; how many barrels per day would that mean?
Thank you for helping me with this.
Respectfully,
Mark Allyn
An earlier calculation (8,000 or 9,000 psi below BOP, 2,400 or so above) of a 1/4" hole gave 5,000 b/day (hot API 35 oil, mixing in gas complicates the calcs). Pressures came from Thad Allen early on.
This hole was expected to erode quickly due to the sand produced with the oil (very normal, but could be worse in a wild well).
Hope that helps,
Alan
The pressure of the sea water at the blowout preventer at a depth of 5,067 feet should be about 2,300 psi. Estimates for the reservoir pressure have varied from ~13,000 psi (figure 2 in this thread) to ~18,000 psi. Using Heading Out's approximate calculation for the pressure under rock (13,293 feet for the Macondo well) in Tech Talk: Revisiting Oil Well Pressures and Blowout Preventers after BP's Gulf of Mexico Oil Spill and adding the sea water pressure, I get ~15,600 psi for the reservoir pressure. Heading Out also mentions that 3,000 psi is "roughly twice the water pressure in the wand you use at a car wash."
Use Mud Weights to Estimate Original Bottom Hole Fluid Pressure ~13,500 psi
Partial Scout Ticket info posted on drillingclub says they drilled the last section of the well with mudwt in of 14.1# (shorthand for pounds, really means pounds/gallon, or density which is equivalent to a pressure gradient) after getting a LOT of 15.9# (thats the point at which the formation or cement began to fail on the previous (9 7/8" liner shoe). At the bottom of the hole, presumably in the pay zone (that's the oil-bearing zone) they mudded-up (raised the mud weight (really density) to 14.4#, but lost circulation (i.e. they broke down the formation or flowed into an underpressured zone. Bottom line is that 14.4# was too much and 14.1# was too little (approximately, because other things affect the effective mudweight, pump rate, cuttings, gas cut, etc -- don't ask).
So, at 18,260 tvdkb that would be a static formation fluid pressure at the bottom of the well between
14.1 ppg * 0.52 (psi/ft)/ppg = 0.733 psi/ft
18260' * 0.773 psi/ft = 13,388 psi
and
14.4 ppg * 0.52 (psi/ft)/ppg = 0.749 psi/ft
18260' * 0.749 psi/ft = 13,673 psi
Shut-in pressure at the top of the well would be this pressure minus the weight of the fluid in the hole -- let's assume its a light oil with about .3 psi/ft -- that gives
13,500 psi - (18000-5000)*0.3 = 9600 psi
gas is, of course, much worse, brine or seawater better -- the right mud gets you to zero.
I have no idea how to calculate the dynamic pressures - I'm just a dumb geologist, but the static calculations are trivial.
BTW, posted scout ticket indicates that they took geotap pressures and I assume they also got highly accurate reservoir pressures from MDT tool.
Bottom line: approximate bottom hole formation fluid pressure was about 13,500 psi, but could be less now.
and the bht ?
Thermal gradients vary areally and with depth, but 1.2 degF/100' is probably close. Temperature at seafloor in deepwater about 40 degF.
(13000/100)*1.2 + 40 = 196 degF.
So, roughly 200 degrees Fahrenheit.
Thank-you for the better estimate of the original reservoir pressure.
Here's the /., Reddit, Digg, and SU links, if you're interested in helping this piece get more eyes. (We do this each day with all of the pieces, I just haven't been putting them in threads lately.)
http://www.reddit.com/r/energy/comments/c6qhd/so_what_actually_caused_th...
http://www.reddit.com/r/science/comments/c6qhf/so_what_actually_caused_t...
http://www.reddit.com/r/reddit.com/comments/c6qhj/so_what_actually_cause...
http://digg.com/d31Rkzd
http://su.pr/2Fs6NG
Thanks for your help. :)
Re: pressures. To put some of these pressures in context. I was on a frac job once with a pipe failure - running a 4000 psi or so, with a 4" pipe. When it ruptured it stripped the paint off a truck in 5 sec, at a distance of 100 ft....
The underwater cam is back up and working from its massive overload last night for those interested. http://www.cnn.com/video/flashLive/live.html?stream=stream2&hpt=T1
This incident reminded me of some rumors I heard a few years ago...
2. Only 51 barrels of cement were used according to the well plan. This was not sufficient to ensure a seal between the 7-inch production casing and the previously cemented 9 7/8-inch protection casing (Figure 2).
I work as a consultant in a different business unit for BP in the E&P segment. A few years ago, there was a mild shake-down at the main office. Apparently, BP had a stable of Schlumberger engineers in the BP office writing all the cementing programs for drilling. It seemed to me at the time, BP just didn't have enough resources (or the resources they did have were too lazy) to write there own cementing programs and they were relying way to much on contractors. I know that our management promptly kicked out a majority of the SLB engineers from the office and made sure BP engineers started writing the cementing programs. At the time, I think the motivation was that BP was getting bilked by SLB for the cementing jobs, but this situation in the gulf clearly shows why you would want to have your own staff writing and reviewing cementing programs.
Makes me think that perhaps they might have had a similar problem in the gulf.
Another thing people just don't seem to get. There is an extreme shortage of qualified people to do this sort of work in the states today. Sure the technology has progressed by leaps and bounds, but there are so many fresh out of college engineers replacing all the people with 30 years of experience in the industry, it is impossible to transfer all that knowledge.
yeah...i had wondered if part of the problem was too many people w/ not enuf experience.....
This also gets to a problem many companies find themselves in today...subcontracting and outsourcing important work that used to be in-house. Sure, it save immediate money on the bottom line, but can hurt unforeseen things down the road.
This isn't a question of whose employees should have run the wire test......there were no in-house testers, and SBM were on the rig. The question is why the wire tests were not done and I will bet a round of drinks that decision was made by BP, who figured that in worse case the BOP would close off the well.
Guess what?
It's not only a question of who was running tests....
It's also who/what experience level did the well design, what eperience level in the people making decision to displace the riser and then not watch the mudpits, etc....
Matthew Simmons highlights this issue of severe shortage of skilled oil workers in his presentations addressing Peak Oil. This BP blowout underscores the critical importance of experience.
What happens to the gas meter after 20:10? It seems to flatline or zero out? even as the pit volume continues to increase, the gas meter is showing nothing...
On the other side of the chart, the drill string load meter seems to be showing that the drill string is being 'pushed' out of the hole by something after 20:20?
We can only speculate what was going on on the rig while all these signals that something is wrong are there to be seen. To get the bottom of that will require suppoenas.
Everything I've seen here indicates shortcuts taken to save money. Shortcuts which resulted in a dreadul distater. The men who followed that plan are dead, the people who pushed the plan need to be called to account.
I wonder when we get to see the logs from earlier in the day - during the negative pressure tests on the concrete?
Not sure we get to see them unless they had telemetry on....Transocean has no records of anything after 3pm. Their replication to the office hadn't happened yet and the records are at the bottom or incinerated.
What's your source for that? The Congressional testimony? I'd like to look that over and try and 'read between the lines'.
I know they had a ship-to-shore data system (from about 2002), in Norway, they run a lot of that kind of stuff in 'near real-time' to the shore and stuff it into a data historian.
can't find the source, but can second the statement as I remember reading/hearing it also.
transocean's data was replicated back onshore every 8 or 12 hours, 3 pm that afternoon was the last replication. Everything else is on the sea floor.
There has never been any mention that I have seen of data that was being sent to BP's offices, so not sure if that was happening or not.
Slatz
Source was Transocean CEO I believe in answer to a question in the hearing I saw.
Right on. The more advanced solutions to this problem use a pub-sub model to queue up data posts to shore so that the onshore is never more than a few minutes at most behind the rig. The idea being that the drilling engineers can get help from onshore in a very timely fashion and spend less time in helicopters. Would also function as a kind of 'black box' in case of disaster...
Wonder what Halliburton has, having the last two hours and not having the previous 12 while the concrete is drying and being tested doesn't sound logical.
Unless there's some jiggerypokery clearly on display in the negative pressure tests that someone's lawyers would prefer not come out at present.
Or some other, better reason (I hope).
Just a guess....but I'm guessing that not everything that happens on the rig is attached to telemetry...
I'd be willing to bet that one of the changes that comes out of this whole sad mess will be that telemetry of EVERYTHING relevant is REQUIRED.
Of course, there will be discussions (arguments?) about whether the conversations in the galley are RELEVANT, but I don't think there will be any question about anything like the drilling parameters!
Nowhere to date have I seen any mention of the TO Toolpusher or the BP Company Supervisor on board the rig. Where were they and what were they doing during this critical operation on the rig, displacing the well with sea water? Did they see and have an interpretation of the data being received or were they at the "party" in the quarters with the Driller being in charge of the operation?
I don't think I have seen this in the above posts - but can someone explain why they replaced the mud with seawater at the point in time they did?
I know the geology but these completion discussions are a bit above my pay grade.
They were preparing to pull the BOP/Riser and move off location. The riser needs to be full of seawater before they diconnect or else all the mud empties into the gulf.
do you know what was the bottom hole temperature ?
A little off topic, but what sort of pay do the various professionals on a rig make? There was a comment above regarding the shortage of qualified workers....Also, what kind of schedule do the workers keep--I assume that very few commute back and forth to shore daily, but are they "on the clock" the entire time they are rigside, and is that for 1 week, 2...? Are unions big players?
Well site leaders as consultants for BP make around $1300-$2000 per day on a weekly or bi-weekly rotation in my business unit (grated, the WSL doesn't see all of that money, a good chunk goes to the consulting firm for insurance, beni's, taxes etc), actual BP employed reps make around $150k per year, also on a rotation and generally come with some sort of degree.
We have a much higher cost of living than most places, so pay will vary from location to location, but I think these rates are pretty common given that a lot of people I know have shipped off to places like the Gulf, Pennsylvania, North Dakota and Algeria for better day rates in the past few years.
As a WSL, I generally work 15-16 hours per day, everyday when I am on site and am available 24-7.
It is a great job, but very, very stressful. Most people either start out with a 4 year engineering degree or wash out working their way up through the ranks and / or take a different career path in the industry.
Good points. I went from service firm to operator, from Libya (land) to N. Sea. From shallow water to deep water, from jack-ups to DP drillships and the stress was more and more. I was a mud engineer and had to learn Italian to work on Agip rigs (the had wine) and same with Forex French rigs. N. Sea was tough commute from London to Stavanger to Barents Sea, long hours. Crew had 12 and 12 and I had 24/7. Our rig had shallow gas blow out and I was on time off. Then, I was in Aberdeen headed to Piper Alpha for a re-drill (new technology) and it blew up. 167 died. By then, I had wife and two young children. I went into management with operator (Conoco) and did not go offshore much - better pay and less risk, except for IRA terrorist bombs in London. I like offshore but stress of 24/7 for two weeks was too much. You think the airlines can do it (unions) why can't oil be more like 747 pilots with the pay and union protection? Oil uses too many young and inexperienced offshore and the older guys are in the Houston offices. Should be the other way around. Maybe this disaster will change the culture - more unions, more whistle blower protections, etc. Norway has powerful unions.
For those who missed the press briefing today I posted a few points on the the "EPA" earlier thread.
Art, this is the best and most understandable analysis of what happened I have seen.
I can't help wondering if management obsession with workflows contributed to this accident. The concept of workflows is that understanding detailed sequences of work, together with the resources required for each step, allows efficiency to be improved by doing everything according to a standardized workflow. In a repetitive process, such as manufacturing or distribution, this can improve efficiency, reliability and safety, because nothing unexpected happens, and what's more costs are lower because each person in the operation only has to know one part of the workflow. Knowing how to implement the workflow becomes much more important than knowing why each step is carried out.
The problem when such concepts are applied to drilling is that every well is different. The standard workflow may be neither the cheapest method nor the safest method in a particular well. The risks are heightened by having fewer people around who really understand what is happening when something starts to go wrong. I'm not an engineer, but I do understand the physics of drilling a well, and if I was seeing that mud pit volume log in real time I would immediately conclude around 20:15 that a lot of people were about to die, real soon. As Art concluded, this was probably due to gas entering the hole, and with the riser full of seawater rather than mud it's hard to see what should have been done at this point, other than shut everything on the BOP and get the rig off site, or if that couldn't be done, abandon ship.
But did anyone on site realize just how serious the situation was?
The history of engineering is littered with major accidents. The early efforts in a field are often overly cautious, and as experience is gained the operators refine the design and reduce safety factors, until eventually something goes horribly wrong, and the bridge collapses or the well blows out. For the next few years everyone is more cautious, designs improve, then efficiency becomes the rage again. And the next accident happens.
There is so much info available about this wreck that it is hard to assemble it, disseminate it, understand it, etc.
Donch'a just wish those same CSPAN cameras the pols who are whoring those cameras would have been equally enthusiastic abou reading, telivising, and helping us understand ObamaCare as President Mubarak Hussein Obama so faithfully promised us before the debate began!!!! I wonder if "transparency" will some day come to mean...."Yeah, buddy, I can see right through you...."
Now if someone will remove that soapbox so I don't trip over it later.......
Mr. aeberman, two of your analyses of the data you presented in your post are basically and critically flawed:
Re: Chronology Item 1.....They pumped "only" 51 bbls of cement to secure the 7" X 9 5/8" casing string on bottom. You further state (by what authority???) that "This was not sufficient to ensure a seal between the 7" production casing and the previously set 9 7/8" liner."
Posted by cutting and pasting from you:
2. Only 51 barrels of cement were used according to the well plan. This was not sufficient to ensure a seal between the 7-inch production casing and the previously cemented 9 7/8-inch protection casing (Figure 2).
Did you editorialize a bit when you injected the word "only"???
I did a quick calculation of 1,192' of open hole drilled (based on your diagram) with an 8 3/4" hole size, then inserting a string of 7" casing, and I come up with a volume of .0268 bbls/ft or a total of 31.91 bbls of cement required to fill that "newest hole dug" annulus. 31.91 bbls required and 51 bbls pumped.... Looks to me like they pumped the required job plus @ 20 bbls of cement. You note the lost circulation problems they had at the end of the job. As a company man of some 27 years of experience, I don't know if I'd have recommended an @ 60% excess of cement on this job.
Neither of us has access (yet) to the open hole log run over the lowest section of the hole, so we don't know what the hole average diameter (caliper log) or gross volume contained. Just rest assured that when you say they pumped "only" 51 bbls of cement, I think you need to repost. Especially in light of the fact that you have no idea the weight of the cement in pounds per gallon. You run without that, and you are pulling numbers from down south instead of pulling them out of a calculator or out of your head.
Secondly, and more important:
In your analysis of the chart of drilling rig parameters (two charts), you "note" (your interpretaion) that they stopped circulating at 21:30hrs and continued to have rapid pit gain. This is absolutely incorrect, and if you don't repost and correct, that will stand before you as an intentional misrepresentation of facts. You either clearly don't know how to read these graphs, or you editorialized the results to your own gain.
Please note the column labeled "flow in gpm" just to the right of the time track. It clearly shows they were pumping @ 1,000 gals/minute during that rapid pit gain. They were clearly still displacing the hole when you say they had shut down the pumps and were taking a pit gain.
You may have an agenda. I obviously have an agenda, and I'll tell you what it is. Some good ole' boys and gals from Louisiana, Oklahoma, Texas, Mississippi, etc. were put in harms way. Eleven of them died. Several (seven or more) were injured, some of them critically. I don't want their efforts or their sacrifice to go unrecognized. Your post with basic critical engineering flaws points fingers at BP because of a judgement call (cement volume), but more importantly, that somehow those in harms way did not react or do the right thing with the equipment they had.
Maybe you just got tired, but you somehow didn't have time to post the fact that the sudden and dramatic increase in standpipe pressure in the last two minutes (from @ 1,200 psi to @ 5,800 psi in @ two minutes) could only result in the fact that the boys in the moon pool shut the well in, and the equipment failed after that.
This was a tough well. I'm not offshore deep water, but I've never seen a well that required four drilling liners. BP made a judgement call that I have made before. Without reward, no one will take risk.
Again, sir, repost. Your original is flawed.
Deeper Cheaper, your thoughts on the cement job test by Schlumberger that never happened........did Obama order that too?
Andy,
I haven't a clue of what you speak. Please link me to some information that Schlumberger tested the cement job.
And as for President Hussein ordering that? tehehehe.....If he reports results, are you going to believe him? Did you go for the campaign promise of transparency?
Respectfully, I would like to have any info about Schlumberger testing the cement.
Deeper
Schlumberger's crew were told to stand down by BP--they were prepared to do a wire test. Read the other comments below.
Andy-
Thats why Hillary killed Vince Foster-- he had a dream this was going to happen.
The Queen of England lent The Royal Black Helicopter to protect BP.
Hillary hid the gun in Lenin's Tomb.
What other explanation could there be?
I'm looking at the two graphs and wondering if you mistook the 2030 reading on the first graph for the 2130 reading on the second graph?
Nope....
Look at item #7 and the chart immediately below it.
d
DC,
At the risk of looking like I have a serious brain cramp, the chart below item #7 ends just after 2100. The second chart after that seems to indicate at about 2130 the GPM (blue line) went to zero. But this is the first time I've tried to read these type of charts so if I'm still way off don't worry about trying to hold me by the hand until it clicks;-) I'll just let it go.
You guys can see the full chart at this link: http://energycommerce.house.gov/Press_111/20100512/Halliburton-Last.Two....
Art
The time of 21:30 would be on the chart below item #8, I believe.
21:30 - no riser flow, no gpm....concommitant increase in pit volume.
Below #8.
deleted
You are correct, the chart interpretation comments are VERY WRONG. It is suggested that there is a pit gain [gas influx] as of 20h12 but this gain just comes from displacing the well to seawater [at almost 1,000 GPM], so mud flows back in the system and is recorded as a gain where no fluid is taken from the system but direct from the sea.
The gas increase seems minor and is normal for such an displacement although I cannot judge the scale 0 - 200.
Question: I have some experience with air entrained concrete. Is this similar to the "nitrogen cement" used in this well?
If so, the entrained bubbles would compress as the pressure around them increased. So 51 barrels at the surface would not have been 51 barrels at the bottom of the hole.
Air entrained concrete is normally 6-8% air by volume. Do we know what the nitrogen cement was?
++PLS
Hi Guys, Did they run a DST? [Drill Stem Test] Would they or should they have? If so, are the results available or will they be made so? Are DST's required? Are they generally part of the 'public record?' Are/would the results be relavent/important? This is a great site and discussion, thank you for it. Jay
Hey Jay,
No, A DST (drill stem test) had no application here. They knew from logs it was going to produce. They knew from mud weight (14.0ppg) that the bottom hole pressure was @ 13,000 psi.
Wouldn't have told them a thing.
Deeper
Hi Guys, OK, so there was a SlumberJay log? If so, how available is it to the public and/or those doing the mitigation? Jay
The collective TOD wisdom seems to be that the technology is fine and the disaster was caused by human error/bad apples.
This often the attitude of 'experts' who overestimate their expertise and underestimate
Donald Rumsfeld's 'unknown unknowns'.
One can't help sneering at the fact that the experts still can't come up with a reasonably precise estimate of the leak.
It appears that the Top Kill will happen on Tuesday.
Anyone wanna bet that Top Kill will be the end of this leak?
IMO, the industry's technological reach is exceeding its technological grasp.
Sorry, but due to their record over many years those experts do not often have to do a calculation in this situation. The prez said he was upset and was going to send his top folks. Okay ,even they say they will not have a better one until next week(and you think that will be exact?). The bigger issue is people who focus on precise numbers when ranges are good enough when dealing with a problem. The experts are working 24/7 on more important things than satisfying press demands for a "number". Many of those complaining the most have little problem solving skill and often no ability to critically analyze the stream of "factual" articles floating around the internet, this includes the admin and congress and reporters themselves.
I suppose that if you don't know anything at all why do a calculation?
Actually, that's completely wrong.
The public and the politicans are covering their eyes hoping it will all go away and journalists are practicing their PR skills.
You shouldn't discourage interested amateurs.
People searching for answers can uncover a lot, like the prof who is an expert in determining flow from realtime images. Surprise, he was right and wow, BP lied.
Engineers always do calculations but managers rarely do. They go with their gut, shoot from the hip, etc.
This on-going hourly disaster has upper management written all over it.
We might revisit the words of Richard Feynman regarding the Challenger Shuttle disaster in 1986 Appendix F - Personal observations on the reliability of the Shuttle:
In the case of this disaster compared to that one, it just sounds like its a different technology but same kind of flawed thinking process going on. My question is, why can't we seem to be able to apply the knowledge gained from such tragedies and use it as a form of reality check in a more general across the board form. There has to be a better way.
"We" can't learn from "our" mistakes since there is a stratification of human specimens that occupy different jobs. It basically looks like managers are pathologically incompetent and things function only because underlings compensate for the idiots ordering them around. This covering eventually fails. Supposedly there are engineers in management but they must be few and far between and also not able to act like engineers since there is a management culture to which they have to conform.
As long as the same pattern of management selection and behaviour persists nothing will change. I am always amazed by people claiming that managers deserve to be paid more since they take higher risks. This is utter rubbish, it is always the underlings who take the fall for management mistakes (and naturally their own as well).
dissident, the only thing utter rubbish is the content of your post. I am an engineer by training and a drilling manager by experience. You know not what you are talking about.
I don't know you and this is not a reflection on you personally. However it has been my experience that there is definitely a general cultural difference btwn hands on managers with engineering backgrounds who are on the job in the field and (usually upper management bean counters) far removed from operations.
This cultural difference has been well documented as a cause of tragedy across very different enterprises over and over again, this is not a surprise, there is a trend here.
You may be more the exception rather than the rule. I strongly suspect that when the investigation into this tragedy is concluded we will find that this cultural divide is a significant component at the root cause of what happened here.
I'm an engineer who did the management thing for a while, and found it pretty much as Dissident described. I then asked to be demoted to engineering, in part because of this. Naturally this depends a lot on the corporate culture, and perhaps more importantly on the size of the organization.
Overall though, I find it sad that people are surprised when corporations betray the "public trust". Corporations, especially large ones, have no interest in the public trust, except so far as they may be forced to. The idea is specifically to pass of any personal liability to some other entity so that the people who make the decisions are not held personally responsible. Their only risk is loosing their job, which allows them to take risks they would not otherwise be comfortable taking. And it does not matter much what individuals within that corporation may believe, as corporate structures are designed to limit such influences, which they do pretty well to varying degrees.
Apparently the rumour about BP telling Schlumberger where to go was correct all along. This was posted by DickB on HPCA around the 15th May:
What is HPCA?
Link please.
And before you ask, yes I did. I got only 90,500 hits.
http://www.google.com/search?hl=en&as_q=&as_epq=HCPA&as_oq=&as_eq=&num=1...
D
This missive has been sliced, diced and dissected several times already.
But it has been reported that SLB personnel left the rig on the day of the accident. It seems to me that there are two key questions: (1) Did the SLB supervisor express concerns about the hole conditions to the BP company man and (2) Did the SLB supervisor insist on SLB personnel being evacuated. As several people have pointed out, we probably won't find out answers to these questions for a while.
Two legitimate sources.
Schlumberger has reported their crew left at 11 AM that morning.
Transocean's rig report from 8-11 AM makes numerous references to "well static". So Transocean is part of a larger conspiracy or the story is BS.
FF
What's "well static"? New term....
There was no gain or loss being measured. Probably visually confirmed on the rig floor through the table.
AH! As in 'well is static'! Thanks!
Trip tank would be a better place to observe it.
Apparently the rumour about BP telling Schlumberger where to go was correct all along. This was posted by DickB on HPCA around the 15th May:
Not sure what "HPCA" is, but the account you posted is word-for-word identical to the one AlanfromBigEasy posted here on May 14. So either this particular written account was making the rounds, or HPCA got it from Oil Drum.
Now this is circular. That's what started the "rumour" off (on the web at least) and it was posted here on the 14th May by AlanfromBigEasy and subsequently picked up and copied all over the net.
Original post at http://www.theoildrum.com/node/6464#comment-623420
I believe I posted that first.
Alan
Amount of oil flow now set at about 70,000 barrels/day
Excellent article. One might restate one line as "estimated rates between 5,000 barrels and 100,000 barrels per day".
According to some fairly understandable processes of estimating. See for yourself in congressional investigation... check about 28 or 29 mins into the testimony.
http://energycommerce.house.gov/index.php?option=com_content&view=articl...
Download http://energycommerce.edgeboss.net/download/energycommerce/2010.05.19.br...
Streaming video http://energycommerce.edgeboss.net/wmedia/energycommerce/2010.05.19.brie...
rpauli,
While anything is possible, the estimates must be calibrated with reality.
The highest oil flow rate that I know of in the offshore Gulf of Mexico is Thunder Horse at 50,000 bopd (http://www.offshore-mag.com/index/article-display/7929620548/articles/of...). The highest flow rates in the North Sea are 46,000 bopd (http://www.offshore-mag.com/index/article-display/24567/articles/offshor...).
These are from wells with fully functioning casing and tubing. The MC 252 has highly compromised plumbing. So what is the reality? I don't know, but I think that 100,000 bopd is highly unlikely, and I would be surprised if rates exceed 25,000. These are obviously guesses.
Art
Reading through Werely's presentation, he does nothing to account for the gas nor type of flow (turbulent, not laminer). He simply takes what he feels is the apparent velocity (debatable) and pipe diameter and determines a flow directly.
Its completely irresponsible for an engineer to do what he's done and I'm sure it will get him the federal funding he so desperately wants for his visual flow meter.
The basic equation for measuring flow rate is Q=VA. where Q is the flow rate, V is the velocity of the flow and A is the area that the flow is going through. It doesn't matter what the pressure, phase state, friction loss, or if the flow is laminar or turbulent. In using the equation the main issue is determining the velocity as the area is generally fixed. Within a moving body of whatever substance the velocity can change as a function of distance from sidewalls, surface, etc.. If the flow is turbulent is simply means the velocity of the flow change over short distances and time intervals. Take an average or extend the distance that the flow is measured over. This is why for accurate stream flows the velocity is taken at two depths, but in general a single depth some distance from the wall of the pipe, shoreline, etc. where friction losses significantly slow down the flow, will get you fairly close. Single point velocity measurements are routinely used. You will have a greater range in errors but its better than any other method tried so far.
I personally feel the value derived from measuring V and A are reasonable. I would agree that the flow rate seems to change over time along with the percentage of oil to gas, and therefore multiple assessments of the velocity and flow composition should be taken and averaged out.
I've seen a lot of discussion on this, and its obvious BP can not give an accurate value. It would be asking them to perform Seppuku, as the natural resource damage assessment against them will be based on this value.
I've also seen the use of anecdotal evidence that other wells do not produce as much oil as this one might. That might be true, but it needs to be remembered that those wells did not blow up. So, while useful to know, its not that convincing, as its still unknown has much an anomaly this well was.
Finally, it would not be that difficult to get good measurements for the leaks. It would not take that much effort to place a velocity measuring device, mag meter, doppler, or whatever that was self contained with it own power and data recorder. It could be placed and retrieved whenever the ROV comes to the surface, or put one on each leak and leave it there till the leak is stopped.
BP would have to be forced into collecting this information as again its asking them to commit corporate suicide. If BP doesn't agree with a flow rate value it would not be that difficult for them to take their own measurements. They have not done so, nor shown any inclination to do so.
Thus a suspect should not be allowed to manage his crime scene and collection of evidence.
I've changed my opinion - I think the flow rate is relevant to what BP tries. The higher the flow, the more risk BP should be willing to accept. If it's 5,000 out of a maximum 50,000 the "first, do not harm" approach is appropriate. But if you're at 45,000 out of 50,000 the risk/reward shifts. Stuff they've avoided due to risk - like cutting apart the riser and attaching a new BOP - become worthwhile.
The fact that maximum flow is around 50,000 bpd, and they are so cautious about messing with the BOP or the riser, they seem to believe these are both substantially constricting the flow.
Speaking of which, can someone explain the fluctuation in the amount of oil they're getting from the RIT? If it's 3,000 on Wednesday and 2,200 on Friday - what does this mean? Less volumes coming from the well? A different mix of oil/ng? They made a mistake at some point?
xazp
In the May 21st news conference the BP rep said it was due to different volumes of gas over the 24 hour period. There is also a need I believe to continually optimize the flow rate to insure sea water does not get sucked up the riser insertion tube. Not sure what that entails but it could increase or decrease the flow rate of oil during the 24 hour period.
Thanks for the link.
http://energycommerce.house.gov/documents/20100519/Wereley.Presentation....
In a couple previous comments I have been pretty derogatory about Prof Wereley's calculations resulting in the infamous 70,000 bpd flow rate from the end of the riser, but I had no idea how far off he was.
For someone who "wrote the book" about flow measurement; when presented with a real life problem he made a number of very basic factual mistakes. I don’t dispute his ability to measure particle velocity but when many of his other assumptions are wrong then the results are also wrong.
Giving him the benefit of the doubt I will assume that at the time he made his calculation he did not have access to materials other than what was being presented by the media or easily available on the internet. I will also give him some slack in not being aware of things that are peculiar to the underwater or offshore industry.
This also a good demonstration as to why obtaining an accurate flow rate is not as easy as it looks on TV and why I think this new task force is going to run into a lot of problems.
BASIC MISTAKES:
1 - He calculated the cross section of a 20 inch ID pipe, the riser is 19.5 inch ID - this error overstates the flow by 5.2%
2 - A video with wide internet exposure filmed May 1 from the other side of the riser clearly shows the drill pipe coming out of the riser and bent to what appears to be almost a 90 deg angle. Assuming the drill pipe has an OD of 6-5/8" (it may be larger) then just the area of the drill pipe entering the riser would result in an error overstating the flow by 12.3%. The error could easily be twice that due to the restriction by the bent piece of the drill string.
3 – He assumed the entire cross section of the riser was flowing oil when it clearly shows that a substantial portion of the flow is gas, not oil. At the time he did his calculation the information was that the GOR was 3,000. With complete oil/gas separation and the compression from the external pressure at 5,000 feet that would mean there would be 20 cubic feet of gas per barrel of oil. As a barrel of oil is 5.6 cubic feet that would make the ratio of gas to oil about 4 to 1. But some of the gas must still be in solution as from the video it appears that the ratio is more like 1 to 1. This probably means he overstated the amount of oil by at least 50% and maybe as much as 75%.
I will assume that as his expertise is flow measurement that his particle velocity of 25.8 inch/sec is correct (see below for some reasons why that may be off as much as 10% or more). Using that as a basis and recalculating the flow using his numbers but correcting only for the above mistakes we get the following:
Cross sectional area is 264.1 sqin based on 19.5 inch ID riser less the 6.625 in drill pipe.
Volume of the total flow at 25.8 in/sec is 6,814 cuin/sec which is 60,679 bbls/day. Just to this point he has overstated the flow by 19%.
Assuming that 50% of the flow is gas reduces the oil flow to 30,340 bpd. This is 58% less than his published estimate that caused all the media hype.
The errors above are not some special knowledge limited to the oilfield. They are errors that any freshman engineering student should be able to catch. I have a hard time believing a professional would make such mistakes, announce his finding on NPR and then go on to talk shows and testify before Congress. I wonder if he will apologize to the American people for deceiving them.
If you are think about getting a good engineering education Purdue might not be the best choice.
MORE ADVANCED MISTAKES:
The following errors are more understandable as the professor has stated that he has no involvement with the petroleum business and presumably no experience in underwater engineering. At the same time it seems incredible that a degreed and presumably registered engineer would blithely assume that he could do an analysis like this without doing even minimal research into the fundamentals of the subject he is expounding on.
4 - The videos from the opposite side of the riser leak show a piece of drill pipe impeding the flow. Not only does this reduce the flow area as mentioned above but it is also positioned so it appears that it diverts the flow up and towards the side that he used to measure particle velocity. That diversion could accelerate the velocity which is the basis of his calculation.
5 – ROV video lenses are very wide angle. As objects move out from the center of the picture they elongate, or if in motion from the center out seem to accelerate. If you are doing a pixel based measurement you would need to know the lens distortion and adjust for it. In some cases the visual distortion can be as much as 25% to 30% by the time you reach the outer edge of the field of vision. As shown on his slide the area where he calculated his particle velocity is about halfway between the center of the screen and the right hand edge. This would indicate that it is possible that the particle velocity is actually slower than shown on his computer by as much as 10% or more.
6 – The riser section was broken and deformed at the end. This will have resulted in some degree of out of round. It is difficult to tell from the video because of the distortion of the lens but from the other side it does appear the riser is flattened to some degree. Without knowing the exact ovality it is difficult to say what the reduction is but it is probably at least 15% to 20%.
I don’t know if the following items will make any appreciable difference but they are certainly questions that should be addressed before making definitive statements about the flow rate.
7 – This is mixed phase flow which any process engineer will tell you will add considerable confusion to flow measurements.
8 – The flow is at an ambient pressure of about 2,250 psi. I know that gases can have a substantial change in properties when under pressure and some liquids also.
9 - A portion of the gas is probably going into phase change as it combines with seawater which might change its real or apparent volume and velocity.
10 – The optical qualities of water are different than air and may compound the visual distortion discussed above.
11 - It is difficult to tell from the video but the flow appears to be laminar changing to turbulent on exiting the riser.
If you take all these facts, and assuming the particle velocity he measured is representative of the entire flow, above I think it is possible to argue a valid case for oil flow rates anywhere from a low of 8,000 bpd to a high of 25,000 bpd emanating from the end of the riser.
But, there is no way to take Professor Wereley's velocity observations and get even 30,000 bpd, much less in excess of 70,000 barrels per day.
The good professor also states that the hole in the kink of the riser is 1.2 inches diameter. I'm not disputing that measurement but I would greatly like to know where he got it. I have spent almost 4 decades working underwater or viewing underwater videos and I certainly could not get that dimension from any of the videos or photos I have seen. Even ignoring the distortion of the wide angle lens the riser is so severely deformed it cannot act as a baseline and the piping off to the side appear to be some distance behind the leak so even if you know the pipe OD you can not use it as an accurate scale.
BP and the task force - how ever their chain of command is set up - allowed a clearly low-ball estimate of the leak rate circulate in the media until it became clearly untenable. During this period the leak rate was steadily increasing, and BP knew that it was, but they said nothing about this fact. When the video was released it became possible for those on the other side of the fence to make a new estimate that also circulated in the media. Two wrongs do not make a right, however the consequence of hiding or obscuring pertinent information from the public has led to an entirely predictable consequence. I predict that the end result will be that reasonable estimates WILL be publicly released for the leak rate over time that account for the gas fraction and the condition of the riser.
I expect that estimate to be closer to what was discussed in this forum.
The information is important for understanding the consequence of this mess - and that includes monitoring the sub-surface movement of the oil and how much and what portion reaches the surface - in order to better understand, characterize and deal with what ever environmental consequences there turn out to be, to plan for the future, and to stop unwarranted speculation in the media (to the degree possible) replacing it with improved understanding of the consequences of our societal choices.
Shelburn, I see your contempt for the 'good professor'. Please remember, this is not the oil industries private playground. Eleven people have died and unknown environmental, social, and economic costs incurred. I frankly don't give a rat's a** what BP's legal problems might be, I don't give a d*mn what kind of 'proprietary' information about the oil field becomes public knowledge. Trust has been violated - there needs to be some leadership here - from the oil patch if you will - there needs to be some acceptance of responsibility - there needs to be some d*am hard work done to fix the problem as soon as is safely possible AND to adequately characterize what has and is happening.
I hear you folks bad-mouthing the 'government' - incompetent, self-serving, making the mess worse, etc. Well take a good long look in the mirror my friend. You don't want the 'government' running the show? Well then let's see some adult behavior from the industry folks - get them out of the back room where they are whispering with their legal department reps and let them see a little sunlight - and maybe a little oily water.
I mean no personal disrespect here, but frankly I'm a bit ticked off.
Interested - I pretty much agree with everything you said above, and it is absolutely true that I have contempt for the "good professor"
As an engineer I am ashamed that anyone claiming to be an engineer, even worse a professor of engineering, could do such as shoddy job of attacking an engineering problem. And to compound his mistakes he pulls in the national media, who don't know any better, and feeds them a lot of baloney all the while holding him self up as an expert in areas where it is is clear he is not an expert.
I don't doubt he is an expert on the optical calculation of particle velocity and I don't question that part of his research, after all I am not an expert on particle velocity. But he did not do even minimal checking of any other portion of his assumptions before reaching a conclusion and announcing it to the world. That is against any engineering principal that I know. And it just plain isn't ethical.
I feel about him as I expect most MDs feel about those few doctors who attach themselves to the Michael Jacksons of this world and feed them drugs while collecting outlandish fees and basking in the reflected glory.
Certainly BP has done a terrible job communicating what is really happening at the well head. The leak has almost certainly been growing on a daily basis and probably still is and BP waited until it everyone in the world could see it before they would admitted it. Makes them look like a bunch of idiots.
You say that BP knows what the flow is but that is only true if you are talking about a possible range, a large range.
Certainly they have a much better idea what the flow is than we do. But would you, or the general public be satisfied if BP announced that the flow was between 10,000 and 30,000 bpd? I would guess that the backlash would be that the answer was completely inadequate, after all a professor from Purdue was able to get an answer plus or minus 20% and all he had was a degraded video to work from.
As I said, I can make a strong engineering defense, using Professor Purdue's velocity, that the oil flow out of the riser end is only 8,000 bpd. I can make just a strong a defense that is 25,000 bpd. And I think the task force that everyone expects to come up with a firm number will have the same set of problems.
By the way I don't believe I ever bad mouthed the government. From what I see I think the USCG is doing a good job (I was going to say a heck of a job).
The only possibly negative comment I have said is that the government does not have the expertise to drill relief wells or do the work being done on the BOP and underwater. In the same post I believe I suggested it might be better if the government took over the clean up and environmental survey operations, although I think for all practical purposes they have already done so.
Shelburn, in my response I was directing some frustration collectively at 'the industry' rather than you specifically, particularly regards the comments about government intervention. The tactic of trying to subvert regulation and oversight because it increases costs but then behaving irresponsibly is offensive and a violation of trust.
Regarding the professors estimate, lets look at it another way. NPR was attempting to do some actual reporting - having sensed that there might be a way to test the official leak number, and given that BP and the response team had not been forthcoming, they took a youtube video to someone who had experience estimating fluid flows from imagery and asked him if he could estimate the oil flow. He did so with very limited information and the number was rather large - the consensus here is impossibly large. I agree that the task was 1) outside his area of expertise and 2)simple context checking could easily confirm that the estimate was likely too large.
However, BP deserved for that very large number to be released. The situation had become a poker game and the stakes had to be raised considerably in order to effect a change in behavior. The message to the general public was that the official number was likely in error, possibly by a very large amount. The professor and his crude estimate did a public service - one he will no doubt take some professional heat for. He has my thanks for being willing to stand up and make that claim and for accepting what ever criticism will come his way. If he gets some funding to improve his methods - scale them up and apply them properly to this situation - then more power to him. I have no doubt that the interest generated about this problem will result in better technical and analytical means to measure fluid flows and would not be surprised if the oil industry found such technology of use.
I am not sure I said "BP knows what the flow 'is'", I'll check what I wrote, however I am very certain that they had a great deal of information regarding what was happening at the leak site and were inappropriately withholding that information from the public - given what had occurred under their stewardship.
You ask "would I be satisfied with any number BP released?" Let me rephrase that to "would I be able to determine the difference between a good faith effort, one undertaken with genuine concern for the public consequences of private behavior and with a sense of urgency, and an attempt to cover their corporate a**?" The answer is absolutely - and about me personally you should already know the answer, or I would hope you would. Beyond that BP's help is required to mitigate the situation and yet they also need help in dealing with a situation they had not anticipated, had not planned for, and don't have all the expertise, equipment, or knowledge to deal with on their own. The situation demands transparency and cooperation and the best efforts of a diverse range of people - including scientists and professors as well as technical people, engineers, and the best the business has to offer.
There remains a distinct possibility that the leak will continue for several months. There is a greater than zero probability that the situation will actually worsen - despite or perhaps even because of the best efforts to stem the flow. Adult behavior, leadership including public leadership, and responsible, effective cooperation is sorely needed.
One can at least hope.
Sorry, I reread your post and you didn't say that you believe "BP knows what the flow is", I misinterpreted a sentence.
I agree that BP would have been much better served by practicing full disclosure but it certainly would not have stopped the clamoring for an exact number or stopped the claims from politicians, etc that BP knows the exact number but is withholding it.
I also believe that BP has a much more accurate range of flow estimates than anything that has been made public. Even if they think they don't need that information to enhance the spill response, they certainly need the most accurate estimates possible for designing the top kill and junk shot.
I think the hyperbole being printed by the media is very damaging. For just one example the beaches in Florida are to this point unaffected and should not see any significant effects of the spill for weeks or months or hopefully never. But tourists are canceling in large numbers due to misinformation presented by the media. This brings an economic hardship to people who depend on these tourists for their livelihood. Its bad enough that entire industries in Louisiana are decimated without extending that disaster without valid reason.
When a professor of engineering from a respected school make a series of definitive statements it is natural that the media will run with it and it is natural people will believe him. For someone in that position of responsibility to feed out that level of misinformation is abusing a position of trust.
One more point before I quit beating this dead horse.
Every engineering student is exposed to the Code of Ethics for Engineers. I doubt if 10% of them could outline that code 5 years after graduation.
As an upper level manager in a multinational corporation I was required by law to sign a letter every year stating that I had reviewed the Foreign Corrupt Practices Act, a several hundred page document. I think every engineer should sign a similar letter annually that he has reviewed the Code of Ethics, a two page document.
The Code of Ethics for Engineers starts out as follows. Please especially note Canon 3, and also 5 and 6. IMHO the professor violated all of those. If we can't count on the ethics of our educators who is going to instill any ethics in the next generation of engineers?
NSPE Code of Ethics for Engineers
Preamble
Engineering is an important and learned profession. As members of this profession, engineers are expected to exhibit the highest standards of honesty and integrity. Engineering has a direct and vital impact on the quality of life for all people. Accordingly, the services provided by engineers require honesty, impartiality, fairness, and equity, and must be dedicated to the protection of the public health, safety, and welfare. Engineers must perform under a standard of professional behavior that requires adherence to the highest principles of ethical conduct.
I. Fundamental Canons
Engineers, in the fulfillment of their professional duties, shall:
1. Hold paramount the safety, health, and welfare of the public.
2. Perform services only in areas of their competence.
3. Issue public statements only in an objective and truthful manner.
4. Act for each employer or client as faithful agents or trustees.
5. Avoid deceptive acts.
6. Conduct themselves honorably, responsibly, ethically, and lawfully so as to enhance the honor, reputation, and usefulness of the profession.
I certainly understand your position and the code of ethics could serve as well for any number of disciplines. It's the cynic in me that can excuse the hyperbole in service of getting some action sooner rather than later, or never. That said succumbing to cynicism is neither particularly noble nor to be recommended to any side in the debate. Its a rough and imperfect world and human failings a fact of life, yet noble aspiration, true competence and skill, ethical behavior, hard work and satisfaction in achievement - these are also facts of life.
I came to this discussion knowing next to nothing about deep water oil production and have learned a great deal - I am sure I am not alone, and I would offer that as encouragement that 'the public' does in fact have the capacity to understand the situation and its complexity. Lets not be too quick to write off the importance of dialogue and the search for a responsible way forward - no matter that the end result will be less than perfect - when is it ever?
In the end we're all in it together, for better or worse.
I agree and the reason I post here is that there is a section of the public that does share my burning desire to know and to learn. I learn a great deal from other posters.
Unfortunately over the last 10 years I have gotten cynical and I have come to believe a large segments, large enough to make a difference, of the general public are no longer interested in knowledge or facts but only what they last heard from some commentator with an agenda - left or right.
When a professor of engineering from a respected school make a series of definitive statements it is natural that the media will run with it and it is natural people will believe him. For someone in that position of responsibility to feed out that level of misinformation is abusing a position of trust.
IMHO, so is the media abusing their position of trust with the public to repeat what the professor says uncritically, no matter how respected his school. The media tend to get caught up in an appealing "narrative," in this case The Gulf Is Doomed Starring Evil BP, and simply report whatever fits that narrative as if it were gospel. The public assumes the media wouldn't be reporting it if it weren't true, and it becomes Established Fact in the public mind, with repercussions that aren't grounded in reality and could conceivably make the situation even worse.
Absolutely. And we can probably add BP to the list of violators of the public trust.
Turns out the professor has been invited to be part of the prestigious panel put together to finally determine the amount of oil leaked since the start of the tragedy. This tidbit came from the May 21st news conference.
I guess the simplest way to look at it is it's a way to ward off media and public outcry that the "hero" was not included. Some how I imagine the rest of the panel may not be so enthused about the professor's contribution.
So much of this is just Oil Spill Theater. As long as the masses are being entertained with tales of heroes and villains, the gummint and the folks dealing with the mess can quietly go about their business behind the curtain.
Whether Prof Wereley is/was wrong in his calculations isn't the point. The fact is he knew that the initial calculations given out (whether by BP and/or the gov't) were incorrect. And was willing to challenge these numbers. As were others.
AND THAT IS THE POINT.
So he is off in his calcs. So what? He did what he thought was best. I'm sorry, the same can't be said of BP.
Both the 1000 and the 5000 rates were obviously wrong. And just as obviously, BP refused to acknowledge anything differently. Until forced to do so.
And again:
THAT IS THE POINT.
Personally, I'm very convinced by Shaelburne's critique of the Wereley numbers, backed up as it is by a broad and deep understanding of the industry, and sub-sea ops. I also think that BP's lack of transparency has somewhat backfired, in terms of public trust / PR.
But ultimately, the severity of this tragedy can't be expressed accurately as a number of leaked barrels. They include, but are not limited to, 11 dead humans, severely damaged ecosystems, jobless communities, etc, etc.
And BP, as the legally responsible party, needs to address these consequences adequately, regardless of how many barrels of leakage they represent. Whatever they amount to, whatever it costs BP, however much it depresses their share price, or even if it bankrupts them. Those are the rules.
I think that the numbers are very interesting, and I'm not disparaging the thought and effort that's gone into debating them. But they aren't that important - it's the real consequences that matter.
IMHO - THAT is the point.
Just my 2 cents, Regards Chris
Chris, I'm thinking that if a more realistic set of numbers hadn't come out (regardless of how they were calculated) which in themselves puts increased urgency for some kind of solution, BP would have been quite content to simply wait on these 2 new wells being drilled. Just remembering how BP initially challenged the CG re the validity of the 1000 vs 5000 numbers.
I am not very optimistic in BP being able to solve this in 2-3 more months of drilling. Hurricane season is approaching. I wouldn't be at all surprised to see this effort taking the rest of this year. In which case, the gulf states are in serious trouble. I live in Mobile and can see the very real possibility of desperate times ahead for those of us here.
I hope BP (or anyone else) can pull some rabbit out of the hat to solve this. Quite frankly I don't give a rip who is at fault, how numbers and solutions are derived and arrived at, none of that is important right now. Doing whatever it takes to solve this problem is what counts.
I'm just not sure BP has the horse-power to do so.
Josh, thanks for your response
Trouble is - does anyone? Shelburne has given us some insight into the effort that BP will be putting in here, and I believe he knows what he's talking about (excerpt from post on an earlier thread)
It's understandable that a lot of people are angry, and a lot of them say that BP are a**holes, but can these individuals suggest any better way of dealing with the spill at source? Well there's the "how many relief wells?" debate, - only time will tell if that was relevant, but apart from that...
And in the meantime, the physical, ecological, economic, and psychological consequences of the spill are getting relentlessly worse, every hour that passes.....
....which returns me to the point I was making. Be very angry at BP for screwing up in the first place, be very angry if they fail to adequately discharge their reparation responsibilities.
But be angry at them for not releasing accurate numbers? I think that's misplaced anger (and I'm talking about many opinions here, not particularly yours).
Regards Chris
Quite frankly, the ONLY method that is likely to work is a successful relief well.
There is a VERY high risk that any one relief well will run into delays at any (or several) of several steps.
The current well spent slightly more than twice the scheduled days of active drilling that were originally planned, and it did not have to mill through steel in the final foot.
I hope and pray that RW #1 will go smooth as silk and inject a kill pill on Father's Day.
The odds are against it.
And BP is gambling with something worth much more than their corporation's market value on a quick and smooth completion of at least one of the two relief wells.
I want better odds. I want more relief wells !
Best Hopes for RW #1,
Alan
It is incredible that the professor is being attacked for being off by a factor of 2-3 when the official BP propaganda is off by a factor of 5-10. This is pure shill obscenity.
The 5,000 bpd actually came from US government sources based on the oil on the surface. Since then neither the government or BP have been willing to hazard a guess as to the actual amount although many people with some technical background who are watching believe the flow went past 5,000 bpd the first week of May, or sooner.
If BP was to actually tell the truth, under oath, say in a Congressional hearing, the conversation might well go like this;
Sen BM: Is the spill more than 5,000 bpd?
BP Exec: Yes
Sen BM: Is the spill more than 10,000 bpd?
BP Exec: Most likely
Sen BM: Is the spill more than 15,000 bpd?
BP Exec: Probably
Sen BM: Is the spill more than 20,000 bpd?
BP Exec: It might be
Sen BM: Is the spill more than 25,000 bpd?
BP Exec: Its possible
Sen BM: Is the spill more than 30,000 bpd?
BP Exec: Probably not
Sen BM: Is the spill more than 35,000 bpd?
BP Exec: Very unlikely
Sen BM: Is the spill more than 40,000 bpd?
BP Exec: No
That would likely be a truthful and accurate assessment of the flow as it can be measured.
I attacked the professor because he is in a position of responsibility and implied expertise, and was disseminating false information that scared a lot of people. Moreover he based that estimate on easily provable false premises, but nobody has challenged him.
It is more than a factor of differential, a factor that entirely depends on choosing a starting point that is an unknown quantity.
There is a considerable difference between the unjustified withholding of an increase of 10,000 to 25,000 bpd and scaring the public with pronouncements of leakages of 50,000 to 60,000 barrels more than actual. The Purdue estimate is over 97,000 bpd.
The media has always treated the governments numbers sceptically but many news outlets presented the Purdue numbers as gospel. If you were to poll the general public I expect the majority would say the spill was about 70,000 bpd, a few would stand by the old 5,000 bpd figure and even less (mostly readers of TOD) would pick a range that is in the area of most probability. And the 70,000 number is directly attributable to Professor Wereley.
None of this in any way justifies BP not being more transparent.
There is also considerable difference between installing a false sense of apathy by grossly underreporting the flow with pronouncements of 1,000 b/d and giving the public, emergency responders and government accurate information from which to make decisions. A legal term that comes to mind is failure to mitigate damages.
BP sticking with 5,000-barrels-per-day estimate for Gulf oil spill, May 15, 2010:
Somebody should invite him here so he can have his work peer-reviewed.
I think that if someone were to point him to the actual data, with which which he could verify for himself that the best producing wells ever, in the Gulf had come in at around 50,000 bpd and that this particular well had not been expected to be among the all time best producing wells. I suspect he would very quickly have revised his maximum flow estimate downwards to be at or under 40,000 bpd.
BP could have come out and said that themselves. Unfortunately they decided to lie about this from the beginning when they decided to allow the media to run with the ridiculous 5000 bpd figure. There is no way that anyone at BP could possibly have believed that number themselves.
If you actually look at the data starting from the day the rig sank there is every reason to believe that the leak started off small and has grown every day since as the restrictions are eroded away by the flow and the sand contained in the oil.
At the time the estimates of 1,000 and 5,000 bpd were made by the government they were probably a reasonable guess, but about the first week of May, when it was alredy obvious the flow was increasing (like from 1,000 to 5,000) somebody made the decision not to explain that to the public.
Maybe they were afraid of starting a panic but, IMHO, the level of distrust is worse.
Shelburn: Finally decided to talk to some friends who have partnered with BP and who have nearby leases and know a lot more about the geology etc. and who are currently having wells drilled in much deeper water. They just laugh at some of the statements coming out of the press and lack of basic knowledge of the public. The gas and the high condensate level of this well does explain some of the lack of surface oil. They concur with yours and other estimates regarding volume ranges. He gave me some other info about the area in particular that makes me doubt the higher rates in the press, but we shall see. Keep up those good posts.
I accept that as being close to the truth back at the beginning of May. When all is said and done I think the experts will tell us that at some point the flow was at least 4 or 5 times higher than 5000 bpd number, maybe even higher for a while.
Whoever had made the decision not to explain the 1,000 to 5000 bpd increase to the public back then, made an even worse decision (granted from the perspective of hindsight) not to explain to the public that things had become even more dire than that...
Sometimes, as hard as that might be, for people who are trying to cover their asses to believe, complete openness and honesty are the best policy. People actually tend to be more willing to forgive if they hear how bad things really are in an open and frank admission, that there is a very serious problem and even that things are completely out of control.
But nobody likes to find out that they have been lied to or misled! Especially when the ones doing the obfuscating are previously convicted felons. I think that BP may have really cooked its own goose here.
I have been reading all of your discussion about what possibly happened and the conditions, procedures, etc, on typical rigs. I've only been involved in the oil industry very marginally, as a student intern during my years as a Purdue student--then I ended up in Midwestern climes working in the steel industry. So I don't claim to know anything at all about this, other than I have seen multiple instances of corporate culture pushing against safety practices, especially when there is a reason to hurry, as some of you have indicated might have been the case on this rig.
It seems like now the main issue is how can we get this gusher stopped, and 60-90 days is not liveable for those who are affected and the seashore, marshes, wildlife, etc.
You all seem to have a lot of collective knowledge. How can we get all the knowledgeable minds actually there and helping to solve the problem? I would love to see all of you there, for example.
Thanks for your discussion.
Hi All, new to the forum. Excellent source of rational, technical, non-politicized information. A few things I can add...
As to Dove's question earlier about the number of wells drilled in the GOM in 5000 feet of water or more, the total number of boreholes in that water depth or greater is greater than 500. That includes sidetracks and bypasses, since frequently operators will bypass a well to take conventional core , or sidetrack out of an existing well to delineate the size of a discovery. Based on the spud dates and TD dates of all the wells, I would guess that more than 100 years of cumulative continuous drilling time have been completed in 5000 feet of water prior to this accident without a significant accident.
As to the logging by Schlumberger as ordered by BP, I believe they ran Openhole wireline logs at TD including Resistivity, Neutron, Density, Sonic, Magnetic Resonance, Oil-based Imager, Rotary Sidewall Cores, and Formation Pressures (and maybe fluids). This says a few things : (1) they were not doing anything with the motive of saving a few bucks - this whole logging procedure is very expensive (2) They absolutely should have had a caliper log to see what the borehole looked like prior to the cement job, and should have been able to plan for any borehole washouts - perhaps that's why they went with the nitrified cement, and (3) it seems improbable after spending that much money on wireline logs that they would skip a Cement Bond log to save money - more likely it involved a separate logging crew (cased hole vs open hole) and they figured they would run the CBL when the completion crew got out there to fracpac the well (big mistake in hindsight)
As to realtime data, I would be shocked if BP and partners weren't receiving every bit of downhole data in realtime via telemetry right up until the moment of the blowout. The costs of setting up such a system so that the engineers and geos in the office can monitor things constantly is trivial.
Does the MMS have requirements for how high into the previous casing string you have to bring cement? Where I work, they typically plan to put TOC 50 m inside the previous casing at minimum. Assuming an 8 1/2" hole, getting 50 m (164 ft) into the 9 7/8" would have required minimum 52 bbl of cement. That's assuming gauge hole. Most places I've been will figure up a gauge hole volume and slap on a 20% excess (minimum) if they are not sure of the hole size due to washouts.
How did you calculate this?
The bottom part of the well [reservoir section] was drilled in 8-1/2" and cased with 7" OD casing.
Bottom part open hole 18,360 - 17,168 = 1,192 ft
Capacity of space between 7" OD casing and 8-1/2" hole = 0.0227 bbl/ft
1,192 x 0.0227 = 27.05 bbl, so if they pumped 51 bbl this would result in a top cement inside the 9-7/8" liner.
Assuming the liner is also 9-7/8" 62.8 ppf, drift 8.500" --> Capacity of space between 7" casing & 9-7/8" casing = 0.0401 bbl/ft
51 bbl total pumped - 27.05 bbl volume used in open hole, leaves 23.95 bbl available to fill the space between 7" & 9-7/8" giving top cement at 23.95 / 0.0401 = 597 ft inside 9-7/8" liner [at 16,571']
Now there is just a minor reduction due to the shoe track which is/was filled with cement.
However, I suspect they had losses during the cement job, this is also illustrated by the Halliburton schematic where the cement also does not reach the previous casing. During drilling they had losses and this was also the most likely reason why they used the light cement.
This is the system they were using:
http://www.halliburton.com/ps/default.aspx?pageid=453&navid=545&prodid=P...
Do you think that the pressure tests would have been on telemetry? They were asked for in the Congressional hearings, and everybody said that they didn't exist. The only thing presented was the log info from Halliburton that is at the top of this post.
Yes
Have to take your word for it...I can only get to the geosteering and MWD bits. But it DOES make me wonder why nobody could produce test results when asked for them.
I believe the data is there. "Test Results" would be subject to the interpretation of the data on the system as there would be no annotations. This is a very powerful system with capabilities to record almost every variable in any aspect of drilling, formation evaluation, cementing, etc. How much was implemented is a guess. The "log" at the hearing is only a selected presentation of select data. It was generated by picking various variables from the database and creating a custom plot. There would be data continuous from spud to the time the satellite transmission stopped.
It is not just a simple "charting" program.
"Production, production, production.
What about production?"
I can hear the refrain in the Supervisor's head.
The gas wasn't the only thing under pressure that night.
If you drive a car and want cheap fuel the blame rests with you.
If you are a banker and charge interest, the blame rests with you.
If you are a real estate dealer selling outer fringe suburbs, the blame rests with you.
If you are a Roman catholic priest opposed to conception control, the blame rests with you.
If you are a landlord charging the maximum rent, the blame rests with you.
If you are an academic teaching the necessity of growth, the blame rests with you.
If you contributed in any way to that pressure, you share the blame.
Their blood is on our hands.
I am always struck by what they call the "chain of events" for any disaster, where severing any one link in the chain would have prevented the disaster. And with this disaster it seems like there are many links in the chain.
My wife was just asking me about the disaster preparations for something like this, and I was just thinking about the links in the chain just related to the failure of the BOP to seal off the well. But there are many links going back from there - some of which we don't know all the details for.
I guess I tend to agree that it is too early to really say with certainty what the important links in the chain really were. I suppose it isn't important that we have all of these answers right this minute - I am sure all of us would agree that the highest priority is to plug up the leaks.
This is my first post here.
Many thanks for the huge effort in preparing such a well though out summary of events. And thanks to the others for valuable insights. My only contact with the industry has been from the exploration side, and I'm mostly a computer guy. Some time ago I used to teach software engineering, and we used to spend a lot of time on safety critical systems, and a lot of the issues that surrounded them. That plus issues of professional ethics. A few thoughts come to mind.
A few people have related this incident to the loss of the Space Shuttle Challenger. There are clear similarities, but I would suggest that looking at the Columbia accident is much closer.
The loss of Challenger is much better known, more dramatic, and in a simplistic analysis at least, derived from a single flawed decision. The decision to launch. What I see here with Deepwater Horizon is not the same. There is no equivalent of a flight readiness review where every involved contractor has the ability (in principle) to call off the launch. Rather we had business as usual, with probably only one or two decision makers, at a relatively low rank, making a mixture of hour to hour management and engineering decisions. That is much closer to Colombia.
The loss of the two shuttles is in other less important ways also pretty similar to DWH. Each accident caused the loss of 7 astronauts, the financial loss was of the order of billions of dollars (arguably the DWH will be significantly cheaper, but we are still talking huge amounts of money.) All accidents result in congressional investigations and a worldwide impact.
But the Challenger accident did have one particularly relevant coda. Richard Feynman's appendix to the Roger's Commission report included this:
Then in the conclusions he writes:
He concludes with this wonderful sentiment:
That said, Columbia is even closer to the nub of the problems. Columbia was lost when a lump of foam impacted the leading edge of a wing, probably punching a hole in the degraded reenforced carbon-carbon structure and, ten days later, the hole allowed plasma into the wing during re-entry causing loss of structural integrity and break-up of the craft. The accident had many fathers. Much like Challenger safety criteria had been relaxed, from nothing must ever impact the orbiter during launch, to an accepted "fact" that foam continued to be shed on almost every flight. Columbia flew with outstanding safety critical flags against the shuttle system. The Columbia Accident Incident Board review wrote scathingly of NASA's “broken safety culture”. One issue that was noted was that the external tank manufacturer (The ET being from whence the foam fell) had had significant staff reductions, and whilst there was a clear safety and quality assurance structure in place on paper, in reality many of these responsibilities fell to people who also had responsibility for the actual construction and shipping of the tank. That NASA paid the contractors substantial bonuses for on-time completion yielded a clear conflict. One where, with no surprises, safety came second. The conclusion here was that not only had NASA not taken on board the lessons from Challenger, if anything it was worse, and that loss of another shuttle was almost inevitable from a whole range of possible flaws.
One might draw an obvious parallel between the MMS's two roles. The recent announcement of the splitting of the MMS suggests that more than a few people have been aware of this for some time, and that the plans for the split were already prepared, and had been for some time.
Indeed this starts to suggest the real problem is much deeper. A lot of the invective and criticism has been directed at BP. With some reason. But what seems to being now suggested is that, in all likelihood, BP were simply the company that had the bad luck to have the first major accident. There seems little to suggest that if the MMS were approving BP's plans, that the other companies were presenting plans of any greater quality. Indeed with such a huge amount of outsourcing, I find it hard to believe that the level of safety culture versus management pressure would be any different in any other company. Indeed I would expect to have heard rumblings here from those close to the industry, especially from the sub-contractors to this effect, if it were so. So, the conclusion is that there is probably a far wider problem. Indeed, from the comments made by those who understand, it seems that the accident could have been avoided at any number of points. That then begs the question. How many other wells have come only one step short of a similar catastrophe?
A counterpoint to a lot of the invective too. It is very unlikely that there is any easy to lay blame. Humans like to lay blame. It give us closure. We move on. But the managers and engineers at BP are ordinary human beings, no more or less competent then their colleagues in other companies, and many have probably worked in other companies. There is very unlikely to be any broad conspiracy. That is what makes it so much harder to avoid accidents like this. The likely culprit is a long term breakdown in safety culture at all levels, and both within the companies, and in the MMS. A lack of strong oversight of the relationship between the MMS and the companies might be considered to be one of the most critical lapses.
As to conspiracy after the accident. I found earlier comments about the influence of the shadowy publicity department at BP little short of hilarious. BP's public relations handing of the incident has been incompetent from the outset. It has broken almost every rule in the book about how to handle such incidents. I doubt a single professional publicity person was anywhere near this. (If there were, they should be sacked forthwith.) Always remember the first rule of conspiracies. Never ascribe to conspiracy that which can be adequately explained by incompetence. There has been more than enough of the latter to last a long time.
Excellent essay.
Regarding the disconnect between management and engineers, the following 2004 article about Shell management misrepresenting their technical success is interesting and illustrative.
I think that we have something similar going on with BP and deepwater plays. Insofar as I know, BP has still not publicly addressed the collapse in oil production from the main producing structure in the Thunder Horse complex.
http://www.nytimes.com/2004/04/08/business/oman-s-oil-yield-long-in-decl...
OMAN'S OIL YIELD LONG IN DECLINE, SHELL DATA SHOW
Published: April 8, 2004
I'd be interested to know what you know about the collapse of oil production from the main TH field.
http://www.theoildrum.com/node/6415
IMO, BP's game plan was that if they failed to disclose the collapse in production, along with more than a six fold increase in water production, from the main field, then the MSM and trade journals would not report the decline.
The disconnect between management/political perception and reality really cuts to the heart of the whole Peak Oil discussion, and the Thunder Horse decline and Macondo blowout are prime examples of the disconnect.
BP knew about the collapse in crude production from their main producing structure in the Thunder Horse complex, the poster child for deepwater GOM exploration, but they deliberately failed to publicly disclose the decline (in contrast to their very public announcements of rising production from the complex).
BP told us that deepwater GOM blowouts were extremely unlikely, virtually impossible. To quote one of the survivors (from 60 Minutes), "Men lost their lives," survivor Mike Williams told Pelley. "I don't know how else to say it. All the things that they told us could never happen, happened."
Since we have documented that major oil companies have misrepresented field performance (Shell) or failed to disclose material production declines (BP) and since BP was obviously dead wrong about the chances of a severe deepwater blowout, what else are they hiding and what else are they wrong about?
Frances--Merci and agreed. Incompetency is more reasonable an explanation than conspiracy, and far more valuable an understanding for the education of problem solvers. "Nature cannot be fooled" indeed. There are too many complexities and risks threatening; we are top heavy. Public relations in flagranto is propaganda, but management soft-peddling is often considered part of the job: boosterism, good salesmanship. When does it become corruption?
The oil is coming ashore now here in Louisiana. We can handle it on the beaches, but our coastline consists mostly of estuarian bays, bayous (rivers and streams), and small inlets made of mud and grasses. Our lower borders are thin margins where young sea creatures are born and nurtured, upon which larger fish feed. Ninety percent of marine life in the Gulf of Mexico depends on this kind of shoreline at some point in its life cycle. Our fishing families and Seafood and Tourist Industries are up hard against it. They don't know how to react to BP, its outsource companies, the US Corps of engineers, the EPA, and so on. All these preventable things "that could never happen" have happened, are happening.
What is the prescription for their helplessness, frustration, and anger? What will save the marshes? Putting conspiracy, civilization end-gaming, and even Peak Oil arguing aside for the moment, does any TODer know what can be done asap?
Musings.............
What will likely happen if a major hurricane develops in the GOM?
1). Will the relief well drilling be impacted severely enough to further delay it out significantly? (IIRC BP is estimating operating completion by August.)
2). How will the insertion tube(s) be affected during a major hurricane?
3). No doubt oil at the surface will spread ashore albeit in likely I assume a more 'diluted' pattern which nonetheless will equate to more ecological damage in totality. Congruently, with the size of the 'apparent' underwater plume how will a major hurricane affect it even if it's 3,000 below?
Ok so these are probably unanswerable musings as too many variables come into play. However it would be informative to understand how drilling operations in general are affected during such hurricanes and what they can do to mitigate impacts through preparation or other workarounds.
I guess what I'm saying is that it appears to me at least that with hurricane season looming not enough perhaps is being discussed on the what ifs. It's almost like the focus is on the one approaching train light and forgetting about the potentiality of the other. Obviously the remedial approaches being contemplated or used now will depending on the technique utilized will be affected in varying degrees if the worst case hurricane situation hits. I'm sure that BP et al are taking that potentiality in consideration.
I know, I know, ultimately it's all a race against time no matter what here.
A good reason to have more than two relief wells, so that the first one to completion is before a major hurricane.
I'm sure that BP et al are taking that potentiality in consideration.
bitter LOL !
Alan
I agree with the idea of trying more wells simultaneously, and that we must try everything else that might work. On the other hand, the idea that we can fix everything we break is simply hubris and part of our technology and progress religion. I recently took a trip over to the Delaware bay, where once there were huge oyster beds and towns and industry that harvested them. Until MSX killed 95% of them, and along with that natural resource went the associated human towns and livelihoods. It's gone, and there are plenty of other examples. If I lived near the Gulf I would be thinking about the fact that change is often permanent. The Gulf faces a dying ocean (now under much greater threat), rising sea levels, and increased storm severity.
I think I pretty much agree with all of that.
The shuttle incidents are very interesting. NASA is a conscientious organization with less commercial pressure to perform than private companies. Yet, not only did they allow safety margins to be eroded once, they apparently failed to learn the lessons and it happened again. That raises the question, is there a fundamental property of collective human endeavor that inevitably leads to disaster?
The fact is that safety does cost time and money, and there is a short-term gain from reducing safety margin, so over time that is what tends to happen, even in the case of NASA. Having procedures in place is generally a benefit to safety and quality, but it still relies on having procedures appropriate for the activity, and people following the procedures intelligently.
Then the problem is who monitors that the procedures are effective? The people reviewing procedures are often subject to the same factors, external regulators become too close to the process they are regulating.
The bottom line is that in any complex operation safety will erode until a disaster occurs, then a lot of new measures are introduced, which then slowly erode again. This appears to as true in the financial sector as in the engineering sector.
". . . is there a fundamental property of collective human endeavor that inevitably leads to disaster?"
A great question Bob. All our best efforts toward education beg to know if it has a good answer, I mean one beyond rhetoric.
Human nature is a mysterious collective of deep wells we are drilling into, penetrating, tapping, attempting to pump knowledge out of. Group dynamics is another, especially risky in such a a populating world. You point to the unmistakable seesaw of failure and success, with progress building upon disaster. It certainly has been the way we have operated, and very well may be the only way to go.
But I'm with you. Give me a problem I can solve. In the meantime let's teach children that there's no substitute for brains, and no room for corruption, by any name.
Anyone know exactly what the top kill procedure will be? I can't find the procedure proposd in detail, simply the words "top kill" are used.
Looking at this, I'm guessing the strategy is "kill the annulus first" but if I have this wrong, pls let me know.
http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk_english/in...
Top Kill is an injection of heavy drilling mud while Junk Shot is an injection of golf balls, tire material, and other materials. Each is independent of the other.
Currently, the Top Kill is scheduled for next Tuesday at the earliest (last I knew). They at one time planned the Junk Shot first but were concerned that if it failed then the Top Kill option might might not be possible due to obstructions in the BOP left from the Junk Shot.
The Top Kill also became the primary method after pressure tests on the BP were more favorable than anticipated.
As always, anyone please correct me if I'm off track here.
My understanding is that the “Top Kill” procedure is as such: first junk like golf balls, tire carcass pieces, small metal parts, etc are injected into the “choke” and “Kill” lines at the bottom of the Blow Out Preventer, (BOP), these will follow the oil flow, and get wedged into the leak reducing the flow to a few hundred barrels per day. Next a heavy mud, “Kill Pill”, will be injected through the Choke and Kill lines. Some of this mud will leak out the original leak path, but most will travel down the well along the path the blowout was taking to the well head. By the time the mud gets down 8,000 to 10,000 feet pressure from its weight will exceed pressure from the oil formation below. The well is now “Killed”, and the BOP can be removed, and replaced without any oil coming out the drill pipe.
http://www.usatoday.com/news/nation/2010-05-22-gulf-oil-spill_N.htm
I voted for Obama, so you know this post is not political in nature. What is he doing? The big O seems to be on cruise control regarding the spill. He's giving commencement speeches, talking about immigration, the EU, etc. and yes talking about the oil spill, but in such a routine, cavalier way. Maybe he doesn't fully realize the potential damage that could occur to the ecosystem of the wetlands, to the fisheries, people's lives.
The oil spill is a situation in which Obama needs to be the parent to the kid, BP. Just having the attitude BP is responsible, so they must take care of this spill is baiting political misfortune, and disaster for the wildlife and millions of Gulf residents.
Obama the the parent and BP the kid? You really do a have a different view. He loves this as it takes the attention off all the other problems he is facing.
Maybe we should just get Jack Bauer.Actually government did step in right away. On this one I think that saying the government did not handle the response quickly is off base. I might actually defend the big guy in this one, except for the feel your pain and I am mad as hell part. Did you notice during this he actually called the head of Spain to tell they needed to cut their deficit.Spoken like a man from Illinois politics,if I ever heard one.
To the extent Obama takes control of the process, to that extent he owns the result.
Good post. I did some back of the envelope calcs on the cement job based on your wellbore sketch. Looks like the 7" liner was set at 18,360' and the previous (9 7/8") at 17,166'. Ignoring the shoe track this is +-27 bbls between the 7" and the open hole from TD to the 9 7/8" shoe (assuming an 8 1/2" hole). The 51 bbls would require an aveage hole size of around 10" to put the TOC in the open hole. I don't know if they ran a caliper log but I would have thought so since they logged a discovery. With oil based mud the hole could be pretty close to gauge but who knows. I worked as a drilling engineer for Amoco/BP for over 20 years and we would always pump sufficient cement for at least 400' of overlap if not more.
mad dog, I believe your intitial premise is incorrect. BP ran a full string of casing measuring 9 7/8 by 7in. Cement job was 51 bbls on the full string.
ExDrllgMgr. My point was that sufficient cement was pumped to cover the entire open hole plus. (Assuming the hole size was close to 8 1/2".) They surely didn't want several thousand feet of cement fill in the annulus with loss circulation problems.
The bottom part of the well [reservoir section] was drilled in 8-1/2" and cased with 7" OD casing.
Bottom part open hole 18,360 - 17,168 = 1,192 ft
Capacity of space between 7" OD casing and 8-1/2" hole = 0.0227 bbl/ft
1,192 x 0.0227 = 27.05 bbl, so if they pumped 51 bbl this would result in a top cement inside the 9-7/8" liner.
Assuming the liner is also 9-7/8" 62.8 ppf, drift 8.500" --> Capacity of space between 7" casing & 9-7/8" casing = 0.0401 bbl/ft
51 bbl total pumped - 27.05 bbl volume used in open hole, leaves 23.95 bbl available to fill the space between 7" & 9-7/8" giving top cement at 23.95 / 0.0401 = 597 ft inside 9-7/8" liner [at 16,571']
Now there is just a minor reduction due to the shoe track which is/was filled with cement.
However, I suspect they had losses during the cement job, this is also illustrated by the Halliburton schematic where the cement also does not reach the previous casing. During drilling they had losses and this was also the most likely reason why they used the light cement.
Folks ,a bit off topic but have any of you taken the time to read the EPA letter on dispersant (pushed by congress) to BP, the BP response and the response to the response? Some interesting details regarding issues and supply of alternatives. It is on the EPA site.
DD, I see the request from the EPA and BP's response on the EPA page
http://www.epa.gov/bpspill/dispersants.html
... but I don't see EPA's response to the response. Is it posted elsewhere?
BP's response seems to be to continue to use Corexit both because it is the only dispersant currently available in large quantities and because of the lack of testing re long term effects of the constituents of the other formulations. Sure would be nice if this testing is done at some point since I imagine there will be a need for it in the future.
The EPA to B statement is that the companies need to make public their ingredients and such but the letters at least address some of the reason why BP chose what they did and concerns they have about a product that was cited on the news as being better and available. It does not loo like they were as sinister as some were suggesting. Also addresses a claim that BP was using something not approved in the UK. There response put that in context.It looks like all parties are trying to be cognizant of risks.
thanks... I'm a bit surprised more isn't known about the various products.
In another OT vein, BP's Suttles was interviewed this morning on NPR. (available as the first item in the "Heard on the Air" section - scroll down on
http://www.npr.org/templates/story/story.php?storyId=7)
He mentioned that there were about 400 people working on the spill response at their Houston headquarters, of whom only about 60 were BP staff. He said most of the remainder were gov't people. I thought that BP had pulled in a lot of experts from other oil companies, academics, etc. not so many gov't resources. He also said the upper limits on BP's bpd estimates were determined by surveys of the surface amounts, which he said had actually been decreasing a bit the past few days. (burn-off? evaporation? he didn't say.) No mention of - or question about - the invisible gallons below.
Uncontrolled wild wells almost always show a decline after a few days/weeks.
This was a controlled wild well at first (BOP pressure reduction) but sand etc. eroded that over time and it came closer to an uncontrolled wild well.
My GUESS is that the spill peaked at 40,000 to 50,000 b/day (@ May 1 ??) and is now in the 20,000 b/day range. Natural decline from a wild well is my supposed cause for the decline.
Alan
The last I saw there was still a substantial pressure drop through the BOP but that was a few days ago. Do you have some new information?
I think your theory is correct in that eventually the erosion of the restriction in the BOP and/or kink will be become large enough to pass the full volume of a reduced flow from the formation but I don't think that has happened yet, and probably won't for weeks.
My guess is the flow is now in the 10,000 to 30,000 bpd range, is still growing but nearing its maximum.
Very easy to make guesses with little factual data.
Apparently the EPA has not yet responded to BP's response to their amended directive.
http://www.cnn.com/2010/US/05/22/gulf.oil.spill/index.html?hpt=T1
...
Despite the continuing use of Corexit, BP is not in violation of the EPA directive, which said that should the company not be able to identify alternative products, "BP shall provide ... a detailed description of the products investigated [and] the reason the products did not meet the standards" required by the agency.
"We will continue to review and discuss the science through the end of the 72-hour window on Sunday, and then we will reach a decision," an EPA spokesman said Saturday.
John Sheffield, president of Alabaster Corp., which manufactures Sea Brat, took issue with BP's response, saying Saturday that the company is "nitpicking my product because they want to use what they've always used."
Sheffield told CNN that he discussed the nonylphenol issue with EPA officials earlier this week, saying the chemical makes up less than 1 percent of the Sea Brat dispersant.
"I've already diffused this issue with the EPA," he said, adding the agency "accepted that response days ago."
The EPA has not yet publicly issued a formal response to BP's letter. EPA officials met with BP executives on Friday to discuss the issue and to explore alternatives.
The EPA said Saturday that it "will continue to work over the next 48 hours to ensure BP is complying with the directive," but did not respond to requests for additional comment.
Perhaps a bit more to the problem at hand. I am but a mere geologist, but those of you who are posting obviously know tubing, pressures, etc.
Might there be a low-tech way to get at some of the oil? I assume that the oil coming from the tubing is at some pressure higher than the ocean bottom hydrostat: Po> Pw at the leak points - Po = pressure of the oil, which would be the reservoir P - various losses. I know that hydrates are a problem, but couldn't they craft a tube - even another riser - with little or no narrowing, that has some sort of simple valving setup, and pressurized the tube to soemthing lower that the hydrostat at the bottom. If you lowered the bottom end into the very near region of the leaks, and had a simple anchoring system, so that the lower tip of the was basically in / over the oil, and then you opened the valve to allow the oil to "see" the tubing pressure, which would be less than Pw at the bottom of the water colum, wouldn't the oil flow to the lower pressure ?
anybody watching the webcam? siphon came out perhaps? looks much bigger....
I have an unanswered question regarding the status of the leak before and after the rig sank.
There was a gas explosion when the well came in in an uncontrolled fashion.
It has been stated that the shear ram was operated in the BOP (but failed to shear the drill string)
The annulus was closed and an attempt was made to disconnect the riser from the BOP.
OK
The rig burned for two days and then sank.
After sinking no leakage was initially detected.
I assume that what primarily fueled the fire on the rig for 48 hours was gas and oil coming up from the well. It seemed a helluva fire to me. Seems the leak was going pretty good at that time.
If the above is the case then what happened after the rig sank? Seems the falling of riser and drill pipe and restrictions introduced during that event were entirely responsible for restricting subsequent flow. Any problem with the logic here?
A couple of bits from reading I could add:
The riser and all associated pipes were kinked for a time, blocking all flow. Possibly the pressure finally pushed some liquid past the kink and filled the riser and started the leak anew.
An additional amount was added by the new holes eroded in the riser at the kink above the BOP. http://screencast.com/t/MjUyODQwYmQ ( may 20, 2010)
Whether the additional amount of 4,000 BPD was estimated solely due to the new leak above BOP or also due to increases in "old" leaks, I am not sure.
But that WAS a heck of a fire — if someone could could calculate the kCals from the fire, I bet we would know how many BPD a deepwater GOM formation blowout could provide. When I saw work boats having to hose down other work boats so they could get close enough to reach the fire with those massive pumps, holy crapz. That was an epic amount of gas/oil flow ignited, and a great number of brave people working to fix it.
I mourn the dead ( many from my state), but rejoice in the miracle of so many survivors.
Interesting reading:
http://www.gomr.mms.gov/PI/PDFImages/PLANS/29/29977.pdf
paragraph 7.1
This is a side issue at this point, but reading the BP drilling application PDF at
http://www.gomr.mms.gov/PI/PDFImages/PLANS/29/29977.pdf
I noted all the crap that is dumped into the Gulf routinely, including rock cuttings contaminated with oil-based mud, water based mud, human waste, etc.
Am I reading this correctly? Is this allowed? Is it restricted closer to land but not restricted in deep water? Or, like I said, am I not understanding something?
I can't tell you how much all of your outstanding comments reassure me that this most likely won't ever happen again. You are oil folks and I make stickers for a living. I remember the terrible feeling I had in my stomach the day I heard that 11 workers had been killed and then the rig sank and oil was leaking from the well 5000 feet down in the GOM. I told my wife this is really bad. At that point it sounded like there was some hope of operating valves with the ROV's so I calmed down for a bit. After that all failed I remember a friend of mine telling me one way to seal the well was a nuclear blast. That really freaked me out so I tried to come up with something less scary. Look I'm not the the brightest bulb in the string and know nothing about what you all do but does this idea have any merit what so ever? I fully understand it is risky as it involves removing the valve assembly which I don't even know what that is exactly. But I just thought that if it actually made any sense at all it might be nice to know something like it was out there just in case something else goes wrong during the TopKIll procedure. I realize it would only be a temporary fix until the “bottom seal” can be done from the relief wells. If this is really dumb it's OK to say so. Thanks for all you folks do for the rest of us. Your work is wicked dangerous like the men & women that work the coal mines. God Bless to you all http://tweetphoto.com/22557188
Nope, no merit according to various discussions in earlier threads. The reasoning - as I understand it - is twofold. First, the risk of fracturing rock in a way that would create additional, dispersed pathways for oil to reach the seafloor. And, secondly, to have any chance of being effective, an explosive - nuclear or other - would have to be placed close to the bottom of the well, necessitating the drilling of yet one more well as deep as the relief wells they are already working on. Once you're down that deep, the relief wells are a better approach.
I've sadly come to the conclusion that all the junk-shots, top-kills, etc are at best hail-Mary attempts and, at worst, diversions to give the impression of doing something until a relief well gets through. There has also been discussion of the possible wisdom of drilling more than two relief wells - three or four are the numbers suggested - to increase the chance for a successful completion in the shortest amount of time.
rainyday - Thanks for your feedback very much - I was not asking about the nuke option. I think that is a bad idea as well. I was asking about this option http://tweetphoto.com/22557188. Using some type of a submersible vessel that is heavy enough to overcome the pressure of the oil and gas at the exit of the well on the ocean floor. If the plug were tapered properly to match the pipe diameter and sufficiently long enough it would provide a pretty good seal. As an added possibility if the plug were hollowed out it could even be attached to a high pressure hose and deliver the drillers mud directly into the top of the well instead of sideways as the topkill is going to do. I fully realize you would NEVER remove the valve unless it were damaged and already allowing unrestricted flow. I also was wondering if the well pipe could take the outward pressure of a tapered shaft without splitting open so I was not thinking of too tight a fit. But if it could just get in there then you could start the mud flow right away. So this is what I was thinking could be prepared and moved into position just in case. The good thing is that since it is like a remote controlled submarine in a way it could be raised and lowered to test it out. The crude picture I showed of an aircraft carrier is just to get the concept across and I figured we must have a mothballed vessel of some type somewhere so you would not have to start from scratch. Thanks for your feedback.
Yeah, the aircraft carrier concept is pretty scary :-)
While I can't pick apart the idea, I can assure you that the engineers have incredibly open minds and have tossed around lots of ideas that usually would have gotten them laughed out of the room in normal times. Who knows this idea, or one similar, might just have been considered.
One thing I seem to remember is the mud pumps might be putting out up to 15,000 psi at the BOP. That is serious, serious pressure. We who don't work with those types of pressures are at a disadvantage because we no visual or mental reference as to the challenges these high pressures pose.
Right The aircraft carrier was just to get the idea across. I've designed up something a bit more practical. A concrete weighted annular ring supported by air ballast tanks with positioning thrusters. In the center is the tapered hardened steel plug with a hollowed out center for the introduction of mud. On the bottom would be a special urethane sealing ring. Hope this gets the idea across better. Obviously would needs lights, cameras, full electronic package but that is all easily done since ROV's must have the same basic things. I even thought that the steel shaft could have a special urethane hydraulic expandable bladder so the fit did not have to be so tight that it could not be removed in the future. Well here it is? http://tweetphoto.com/23736593 Thanks again Dave
Dave,
I'm not an engineer but I did take a look at your drawing and it is obvious you put considerable work and thought into it. While you might get some engineers on this site to comment on your design, why not submit it to the Deepwater Horizon Response Team?
You can check out this link for how to do it: http://www.deepwaterhorizonresponse.com/go/doc/2931/546759/
PriorityX
Thanks for your feedback. I did submit the idea. Of course they would have to have the engineering done by folks who design vehicles (ships) like submarines or the like. If the idea actually has technical merit I'm sure they could get engineers on it right away as this sure is a top priority for bp and the Govt. I read a tweet (unsubstantiated) on twitter tonight that there may be leaks starting to show up around the well casing on the sea floor and that there are concerns about blowing the top out of the BOP with the topkill. Maybe that is why it is now delayed again until Wed. I sure hope this gets sorted out soon for all involved. Thanks again Dave
If the platform had not sunk, the spill could have been contained much easier and faster. It was the sinking of the platform that complicated the whole thing. I would like to know why the platform sank. I have been directly involved in the construction of these semisubmersables and I can assure you that these things are virtually unsinkable. The internal buoyancy tanks are compartmentalized in a fashion, that should one or more tanks flood, the other tanks will keep the rig floating. It may list or even roll, but it won’t sink. There is more going on here than is being said.
"virtually unsinkable" .. like the Titanic?
Pictures of the platform taken before it sank showed a definite list - one half virtually underwater. I'd assumed that a sufficient number of tanks in the other half were compromised due to flying debris, intense heat to the extent that they, too, took on water.
What do you think might have caused it to sink?
Could they have dealt with the crisis more easily by forcing the BOP while the fire burned above? Seems like the ROVs weren't operating - trying to close the BOP, etc.- until the rig sank, but I assume they might not have been in the area initially.
Is it possible that the fire breached the tanks and the efforts to put out the fire compounded the sinking problem? It'd be interesting to understand what could have caused it to sink. I guess I just assumed that when a ship catches fire and suffers that much structural damage that sinking is inevitable. Maybe that's just ignorance talking.
This is a long thread from a few days ago but a portion talks about the sinking. Two theories, debris from the drill floor punched a hole(s) in the pontoon, or water from the firefighting sunk it - or both
http://www.theoildrum.com/node/6442/619709
rdeauxr: Since you have been involved in the construction of semi-submersibles like the Horizon, can you tell me about the Diesel Generator Room? Is it made gas-tight? I have been theorizing as to the cause of the explosion.
According to the crew member's story on 60 Minutes, he heard the Diesel Generators speeding up before the explosion. I am surmising that gas was leaking into the air intakes to make this happen. The governors will reduce the fuel to the injectors but if gas is coming in the air intakes, the engines will speed up untill the overspeed trip actuates and shuts off the engine. Some engines trip by shutting off the air, which I would think be the preferred mechanism on an oil rig.
If these engines oversped and tripped or caused an over voltage condition on the generators, this will cause the circuit breakers to trip. If gas was in the room and the in the vicinity of the breakers, interupting the current will cause an arc in the arc chutes of the breakers. This could be the ignition source for the explosion and fire.
From my old American Geological Institute AGI data sheet book:
1 BBL oil = 5,800,00 Btu
"Two trillion btu per year are approximately equal to 1,000 barrels per day of crude oil"
Considering the various estimates of crude erupting from the wellbore, the wonder to me is not that it sank but that it took as long as it did to sink. There have been natural gas blowouts that have melted down entire fixed platforms. One land blowout that was described to me melted the rig down in 15 minutes and all that was left was slag on the ground. All that was left to various trailers on the location were black square outlines on the ground.
Nuclear bombs have been suggested by some however note where Mississipi Canyon 252 is located essentially at the base of a steep underwater structure. Such a bomb at the wellhead would cause an underwater land slide that could in turn trigger a tsunami. In addition there are lots of other subsea oil production equipment in nearby blocks that could in turn produce blowouts or pipeline ruptures from an underwater landslide.
http://www.newscientist.com/article/dn272-underwater-landslides-cause-mo...
Drill a hole at depth for a nuclear bomb would require much larger diameter well bore that what is being drilled and would present a host of engineering issues.
Should they remove the BOP, instead of inserting a tube, they will attempt to remotely affix a new wellhead which my understanding is now on the Drillship. This has always been the "classic" way to kill one of these beasts. The scenario that I see if this happens is the well puking out a minimum of 25k bbls and possibly 35k bbl per day rate. This would approximate to a range of 700 to 1000 gallons of crude per minute at a pressure of around 12,000 to 13,000 psi. The psi vs mud weight calculations by others in this discussion are in range and I think reservoir pressure is declining slightly but still formidable. As the well head approaches this flow there would be deflection on the flange that would cause the well head to drift. Whether they can do this process with ROV's, I havent a clue. Somebody knows but they are most likely in that room in Houston right now.
In regard to the engines overrunning - yes that happens. With that much gas it was inevitable to ignite. Could have been any number of ignition sources although most everything on the rig floor is "intrinsically safe". Often open hole blowouts are ignited by sand or debris blasting out of the hole and static discharge. This was a cased hole blowout but with debris ejected-"cement".
In my mind the only solution since deep water drilling began is a relief well. The focus of discussion will probably turn to this process in the coming days. The relief wells will be no slam dunk, but they will work.
My comment relates to the mud loggers chart (drilling parameter chart). I have spent many years in the drilling rig buisness. I always considered well control to be 'core competence' of drilling contractors. As such I am familiar with well control events and the subsequent incident investigations into the these events.
I have spent many hours evaluating the mud loggers chart above together with various other related snippets of information pertaining to the events immediately before the uncontrolled release of hydrocarbon at surface (the drill floor and adjacent areas of the Deepwater Horizon).
I must firstly state that I have been and continue to be remote to the whole event with no involvement whatsoever with proceedings, that I have limited information (relative to what is probably available) upon which to base opinion, and that any views and opinions expressed here-in are solely my own.
One interpretation of the chart is as follows;
The Block (hoist) Position remains constant throughout the period. It is assumed that the drillpipe in the well has been spaced out to ensure drill pipe tool joints are clear of the shear rams on the BOP as per good operating practice prior to commencing with a well displacement activity.
At 20:03 the rig began to pump sea water into the well to replace drilling mud with sea water over a predetermined section of well as part of the negative pressure test on the well. The pump pressure (on chart as SPP - Stand Pipe Pressure) increases as lighter sea water has to push the heavier mud down the drill pipe and up the annulus back to the rig. When the sea water reaches the bottom of the drill pipe it turns the corner and starts to move up the annulus, and as such the pump pressure (SPP) decreases allowing the pump rate to be increases (see Flow in gpm increase commencing at 20:14 and the correseponding Flow out gpm a minute or two later (due to fluid reaction lag time)). All would seem well.
At approximately 20:28 and lasting until 20:35 the Flow out gpm shows an increase whilst the Flow in gpm remains constant. Note however the Trip Tank Change (decrease) over the same period, which may indicate the Flow out gpm anomally was as a result of the Trip Tank being emptied. A similar anomally occurs in Flow out gpm at around 20:59 lasting to around 21:09, i.e. Flow out gpm increases whilst the Trip Tank Change shows a decrease over the period. However note also the decrease in Flow in gpm during the same period (operation is approaching the end of the first part of the displacement activity) which makes the second Flow out gpm anomally from 20:59 to around 21:09 show up more prominently than the first.
In addition the Flow out gpm during the course of the period from 20:18 through 21:09 shows an increasingly erratic trend compared to the Flow in gpm for the same period. Without other prior Flow out gpm data to review it is not possible to conclude if the Flow out gpm behavour observed during this period is normal for the rig specific system arrangement or if this was an indication of increasingly irregular Flow out gpm behaviour (an influx from the well). Of interest also for this same period is the increase in Pit Vol Change, another potential influx indicator.
At 21:08 the first part of the displacement activity is completed and a section of the well drilling fluid has been replaced with seawater to above the BOP Annular.
The next step is to displace the drilling fluid in the Kill line with sea water. The BOP Annular may then have been closed, keeping the heavy drilling mud above the BOP whilst the Kill line is opened (on the side of the BOP and below the Annular) to allow the sea water to be pumped up the kill line back to the rig. Note that the route that fluid from the the Kill Line takes is not monitored by the mud loggers Flow out gpm.
From 21:10 to 21: 20 the SPP shows an increase, note that when the pumps are off (Flow in gpm =0) the SPP trends higher with time. Note also at the end of the period (21:30) where the Kill line has been displaced from drilling mud to sea water that the SPP continues with its upward trend. If my assumptions that the drill pipe is filled with seawater, a section of well annulaus is filled with sea water, the Annular is closed, and the Kill line is filled with sea water then the SPP should be 0psi at 21:30. it is in fact approximately 1200psi, increasing to approximately 1750psi by around 21:35. Accepting the foregoing the 1750psi at 21:35 is a clear pressure anomally that needs careful consideration before continuing with the operation.
The mud logger chart has provision to monitor two Choke Pressures but no provision to monitor and record kill line pressure. If it did, would it have shown a pressure similar to SPP, indicating pressure under the BOP?
At around 20:36 a sharp dip in SPP is seen. Is this an attempt to bleed off 'perceived trapped circulating pressure' to determine where the pressure is coming from?
At around 21:40 another dip in SPP is seen, together with an increase in Trip Tank volume. Is this an attempt to bleed off well pressure into the trip tank where the rate of fluid flow can be monitored more accurately?
At around 21:42 the SPP has dropped to around 350psi, but then gradually increases to around 1100psi at 21:46.
Were the changes in SPP from 21:35 to around 21:45 attempts at identifying why there was an SPP anomally?
Above the BOP Annular is drilling mud, below the BOP Annular down to the drill pipe and all the way back up to the drill floor is seawater. If the BOP Annular is opened at this point there would be an immediate approximate 2000psi increase in SPP (the effect of the heavy drilling mud above the BOP Annular and extending to surface in the riser to drill pipe annulus, acting down on the sea water which extends from the BOP Annular down to the end of the drill pipe and back up the drill pipe to the rig at surface (an effective U-tube imbalance of around 2000psi).
At 21:48 the mud logging chart records a significant peak in Flow out gpm, followed by a much more significant peak at approximately 21:49. This chart record of Flow out gpm at 21:48 to 21:49 is typical of that seen when trapped gas is released and allowed to freely expand as it travels up a column of fluid expelling the fluid as it goes. This is the point when the event became an 'uncontrolled release'.
However the uncontrolled release could not have happened if the BOP Annular was closed, with its integrity intact. A key assumption in my explanation above is that the BOP Annular was closed at around 21:10 prior to commencing the second part of the displacement activity required to undertake the negative pressure test of the well.
If the BOP Annular was closed and remained so from 21:10 onwards then the uncontrolled release should not have happened.
Accepting the above, there are some key questions to be answered, including;
- Did the BOP Annular fail? if not was the BOP Annular opened, and if so on what basis of understanding of the well condition?
- There were some clear anomalies (influx indicators) appearing from 20:00hrs onwards, were these indicators recognised? If so, was adequate time dedicated to evaluating and understanding the indicators before proceeding with the next step of the operation?
In my discussion I have focused on the events of the 2 hours leading up to the uncontrolled release of hydrocarbon at surface (on the drillfloor and surrounding areas of the Deepwater Horizon), utilising primarily the mud loggers chart above. I have not included any discussion on prior related issues, such as a communication path between the well reservoir and the well itself, I have simply assumed it existed, and those far more qualified in that area than I can offer better opinion as to why this communication path came about in the first place.
A final word, my discussion as relayed above is one of a number of ways to interpret the mud loggers chart, there are others. My aim in writing is simple, to assist the efforts to ensure this kind of event never happens again.
Thanks for reading.
BOPE:
I have printed your message and am looking the chart over. The procedures that they were performing is here:
http://energycommerce.house.gov/Press_111/20100512/Internal.BP.Email.Reg...
Some comments regarding the chart. This chart was no doubt constructed from data after the accident with parameters that someone at Halliburton thought would appropriate for the hearing. That is the reason I suppose that "cement pump pressure" was on the right to show that there was no cementing operations going on. I would much rather seen pump stroke rate in that column. There is a bit of "tight holeing" going on as we are seeing the presenation that they wanted us to see. At some point we may see the pressure, individual tank volumes instead of just PVT and trip tank (to see what was transferred where). We may also see a chart that will show the last 15 minutes and based on seconds not minute scale. There may not have been loggers on the rig while this was going on with transmission of data to the Real Time Operations Center. There could have been alarms set at the RTOC(flow in/versus flow out). I doubt it though.
I as are you, not involved with any of the parties involved in this accident. I am not involved in well control and in fact have been working in areas of normal and subpressured reservoirs for a while. You can get in trouble with those reservoirs as well, but not normally the risk that geopressured reservoirs have. I do have experience in the past with pressure detection and pore pressure estimation "back in the day" as a mudlogger. I think ultimately ,when I have time, I will draw my own well schematic and do my own capacity/displacement calculations. A U-Tube plot for what you have described would be useful to get my mind around this as well.
Thanks for your thoughtful post.
Frontier_Energy,
Thanks for your comments. I had considered the procedure in my interpretation, and i had assumed the operation had reached the end of point 4 prior to the uncontrolled release event.
4. With seawater in the kill close annular and do a negative test - 2350 psi differential
5. Open annular and continue displacement
However I assumed that the annular was closed first before displacing the kill line with sea water, this is the most practical way of achieving a kill line with sea water, and also this was how I interpreted the various flows in and out etc on the mud logging charts.
I agree with you on the fact that there is more detail on the actual drilling parameters available to the investigation team, and that we have only been given some of this detail for now. The mud loggers chart may have been pulled together after the fact, however each line is real time data.
I must say that it is a blessing that this data made it to shore. Without it would have meant the good possibility of an ineffective investigation and list of corrective actions and recommendations. One recommendation that should be considered is that the Drilling Contractor also has real time data link between the rig and the operating office (in a plane the black box is part of the plane, not a piece of passenger luggage). The Drilling Contractors data in this case remains with the rig, and may not be protected sufficiently to survive the event.
A bit of general info here for the lay man. Typically the Drilling Contractor has a data acquisition system measuring and recording important drilling parameters, very similar to those seen in the mud loggers chart. The display is available for the operator (Driller) at his work station (drillfloor) and his supervisor (Toolpusher) at his office. Mud logging companies introduce a second set of measuring transducers (or sometimes piggy back off the Drilling Contractors transducers) and data from these are recorded at the Mud Loggers office as critical records of the well construction events, and are relayed to the driller, the toolpusher and the Oil Company Representative on screens that can be set up to display the ongoing trends for the critical parameters. the difference in this case as compared to most well construction operations is that the real time data is also sent to a Operations Centre onshore. The trend data on the mud logger screen is one of the most important tools for the whole team. Something very close to the mud logger chart above would been displayed at the Drillers, Toolpushers and Company Representative workstations/desks, they, in addition to the Mud Loggers themselves, all would have had the ability to monitor ongoing operations.
When wells have a problem then indicators of this problem show up in the changing trends of the parameters being displayed on the mud loggers screen. In this case it was no different. Indicators that a problem existed with the well are apparent on the mud logger chart above.
However the problem being 'spoken' by this well remained within the capability of the equipment and personnel onboard as long as a) the BOP remained closed, and more importantly, b) the personnel onboard were aware of the problem and were evaluating and interpreting the well 'messages' appropriately.
Another piece of general information for the lay man is that whilst the Operator is always accountable for what happens at the work site, he, by the nature of the complex structure of sub-contractors required to undertake the challenge of drilling a well, has to delegate responsibilities to the sub-contractors. The responsibility for operating the BOP is with the Drilling Contractor, and rightly so as it is his equipment and people working on top of the well. A Driller is fully empowered to close the BOP whenever he believes there is a problem with the well(such as an influx of formation fluids into the well bore)that might result in an uncontrolled release from the well. Similarly a Drilling Contractor must be fully assured that there is no hazard beneath a closed BOP (such as gas) before he will open the BOP.
Thanks for reading.
At 20h00 the negative test was already done [there is 1450 psi SSP showing that the mud above the 3300' of seawater pushing through the DP] Remember that testified was that the test was performed 16.5 hours after the cementation [this was finished at 00h30] so the displacement of the 3300' to seawater must have been around 17h00. It could well be that the negative test was completed just before 20h00 and after that the BOP was opened. Unfortunately the data between 15h00 and 20h00 are not provided, unacceptable I would say but who am I? We cannot even check if the test was performed correctly but fact is in my opinion that at 20h00 the annular was open resulting in the 1450 psi SSP. Next I assume they closed the annular and bled-off SSP to zero. Then they started the pump at 20h03 and when they were above the 1450 psi they opened the annular again in order to displace the riser from wellhead at 5067' to surface to seawater. When around 2/3 of the riser was displaced to seawater the blow-out occurred. In my opinion the casing string was ejected into the BOPs or collapsed by the 13,000 psi reservoir pressure due to underbalance caused by pumping the seawater. I challenge you to calculate the force working up against the casing string versus the down force, assuming the cement plug of a few hundred feet was leaking and breaking up due to this upward force. The ID of the 16" casing is 15.01"
I wish they had included Transoceans well control procedures in the hearing as that would have given some idea on what they were supposed to do by company policy.
Most of the calculations are available in the book: Formulas and Calculations for Drilling , Production and Workover by Norton J. Lapeyrouse. Chapter 4 "Pressure Control" is specific to this discussion.
Unfortunately, I kind of have my hands full at the moment but I definitely plan on sitting down and working through some of this with the little information that we have available.
BOPE Man,
Thanks for your analysis. I look forward to hearing more from you as additional data becomes available in the coming months.
The list of mistakes by BP is long, too long to allow BP to operate any oil & gas leases in this country. I was not there but have heard from several who were and the following is spot on or damn close.
a production liner w/ subsequent tie-back to surface was originally planned but last minute changed to the current full string design- (without any consideration of the fact that at least 36 hrs would be saved and the completion rig was on the payroll, WAITING)
very little circulating & conditioning of mud was done prior to the half assed attempt at a cement job- 51 bbls of nitrogen foam cement
seven BP executives were on board to celebrate the MMS safety award, were the 6+ BP supervisors (yes at least 6, can you imagine the confusion) involved in the party while the 11 poor souls were left to implement such a flawed plan?
Today there will be a service in Jackson, Mississippi for the 11. I did not know them but several came not too far from where I grew up. They will be in my thoughts today.
BTW, I have "Run off by BP" on my resume- I know what kind of idiots they have. I can't say that I am unbiased.
I've redesigned my submersible well plugging tool presented in an earlier thread.
This submersible tool or “vehicle” would need to be heavy enough to overcome the upward pressure of the oil and gas. It has the added benefit of being able to be used as a “Mud Injector” to possibly seal the well from the top. In addition the plug shaft could have a new control valve and a new BOP valve attached to the top just in case something goes wrong. This hollow shaft will also allow for the plug to be positioned while the oil is flowing so as not to shock the flow. The plug shaft would be up 20 or 30 feet long or more and the sides could be equipped with hydraulically operated bladder seals so that the plug itself does not crack the well pipe. Once the side seals are activated and the plug is sealed in place the mud flow can be started. This side seal technique would also allow for the plugging tool to be extracted after the well is permanently sealed. The vehicle could then be used again if necessary. Hopefully NOT.
Just wondering what you folks think of the idea? I make stickers for a living but enjoy solving problems. Does this idea have any merit or is it totally off the wall? Thanks Dave
http://tweetphoto.com/23817974
@Frontier_Energy
>>BOPE:
I have printed your message and am looking the chart over. The procedures that they were performing is here:
http://energycommerce.house.gov/Press_111/20100512/Internal.BP.Email.Reg...<<
Isn't that procedure the source of the 'argument' between TO and BP's Don Vidrine? Am I wrong in thinking BP has said the log of what really happened is on the sea floor?
Thanks in advance for making this more clear.
Apparently the procedures in the email or possibly a specific point on the list. It is not clear when this argument took place. Without further information given, I will make some assumptions/conjecture:
There was probably a safety meeting for the oncoming "morning tour" crew coming at about 17:30 where a safety topic and then the specific operations were discussed before coming on tour. There would have been a discussion of current operations and whether specific issues were giving problems. Apparently this was the last tour for the morning tour crew for the hitch. There probably were comments in regard to this as a safety regard as it has always been mentioned in every safety meeting that I have been in under the circumstances. Mike Williams, who was interviewed stated that there was some chest bumping and disagreement on procedure. There shouldn't have been an argument as there is a procedure by MMS "Subpart G -- Abandonment of Wells
Sec. 250.110 General requirements."
The procedure shouldn't have been up to BP. I'm not a deepwater hand but it would seem to me that if you have a variance from the MMS procedure, somebody at MMS better sign off on it.
In regard to the "log" - all of the realtime data should be at the BP realtime operations center. There was not just a simple "chart" being transmitted but rather a real time data base. In this database there is a data field available for almost any conceivable operation and sensor on a drilling rig. Whether sensors were available and enabled to the database would be the question.
You may have see various oil company commercial where they show holographic visualization going on showing the formation layers, reservoir and a well bore poking through the hologram- this is where the data is coming from. This is not a simple chart program.
Also the program has a "replay" function where the data can be replayed in whatever format you want - gauges, charts, bar graphs what ever you want to see and played back as though it were happening now.
In my opinion the database should be secured as evidence.
tvhawaii
Toolpushers and Company Men disagree from time to time, the important thing is that such disagreements are dealt with in professional way, and not in front of the team.
I can not talk to the 'argument' at all, sorry.
I can offer that the computers storing the drilling parameter data recorded on the rig, i.e. the Transocean data and the mud loggers data, are most probably on the sea floor. However some real time data did make it ashore (see also an earlier post of mine above), and some of that is shown on the mud logging chart above.
Drilling Contractors generally do not send real time data to shore, rather they store it on their data acquisition systems. They also maintain a daily log (IADC Report), which formally records activities on the rig. This too will likely be on the sea floor. It may be time for Drilling Contractors to consider black boxes, and or real time data relay to shore (the latter is not always favoured by the Operator as there may be some commercial value associated with some of the drilling parameter data)
Thank you.
A $400 millon rig on a well costing more than $100 million and a debate about data? There should be milli second data sent via satellite, microwave, cable, etc. "ship to shore" as this is the 21st Century. Am is thinking this is 1982 when we faxed the IADC report and the company man faxed his report via "ship to shore" or Immarsat faxes? As the Amoco Cadiz slowly drifted to the pristine French Coast in 1978, the master was speaking "ship to shore" to his superiors at the Amoco Tower in Chicago. The VPs did not want to give the cargo to salvage under admiralty law so they hesitated too long fighting with the master and salvage tugs (and admiralty lawyers). They eventually, like BP, lost the VLCC and the cargo. Don't we ever learn? Guess they never did as Amoco is part of BP.