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“Top kill” fails to stop flow of oil in Gulf of Mexico

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NOAA-spill-map-May-28-2010Despite golf balls, tires, 30,000 horsepower of pumps and 30,000 barrels of dense drilling mud chock full of barite, BP’s so-called "top kill" operation failed to stop the disastrous oil leak in the Gulf of Mexico and was abandoned on the afternoon of May 29. The idea was to muscle the oil back into the well with a steady stream of mud—a technique that has worked on land.

But with 5,000 feet of pipe just to get to the blowout preventer and wellhead, the mud was never able to overcome the flow of oil and silt up the well, said BP Chief Operating Officer Doug Suttles at a press briefing. BP now will move to attempt the so-called lower marine riser package technique, which involves cutting the riser pipe free from the blowout preventer and putting a cap—not a top hat—over the pipe, hopefully eliminating all the oil flowing into the sea. The package is already resting on the seafloor but it will be four to seven days before BP makes the attempt, said Coast Guard Rear Admiral Mary Landry. BP’s Suttles says placing such a device on top of a blowout preventer has never been attempted before at a deep water well, such as Mississippi Canyon 252, which may have released as much as 40 million gallons of oil into the Gulf of Mexico to date.

In the meantime, 170,000 gallons of dispersants have been injected beneath the sea surface to break up the oil, which has been flowing now for 40 days, though Suttles noted that BP would not be able to remove any of the dispersed oil in sub-surface plumes. BP continues to use the dispersant Corexit, which can include toxic solvents such as 2-butoxyethanol. To date, 930,000 gallons of various versions of Corexit have been used, both at the surface and near the well.

The failure of top kill is a major setback as BP had offered a 60 to 70 percent chance of success. Suttles declined to give an estimate for the lower marine riser package effort, but expressed confidence the effort could work. "We do have a lot of confidence, but I’m not going to quote a number," Suttles said. "There clearly is a risk it won’t work." He also noted that it would be easier to watch the effort unfold as the mud involved in top kill had obscured the view previously.

Regardless of the success or failure of the package, the flow at the well will not be fully stopped until August at the earliest, when at least one of two relief wells being drilled intersects the currently flowing well and cuts it off. Added Suttles: "This scares everybody, the fact that we can’t make this well stop flowing, the fact that we haven’t succeeded so far."

Image: NOAA

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  1. 1. jtdwyer 9:57 pm 05/29/2010

    Yeah, the pressure applied to the reservoir’s methane and oil, produced by Earth’s gravitation 5,000 feet below sea level, may be a bit more than for the surface wells to which this method has been successfully used in the past. A surface well’s reservoir could even be above sea level.

    Of course, I’m not one of the expert physicists advising the president – I’m just guessing. I sure hope someone guesses right real soon!

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  2. 2. JoeyC 10:01 pm 05/29/2010

    If our government gave a rats behind about us they would of tested the fail safe devices first maybe with rigorous government studies, the concrete mixture would of been to to three times the spec’s required, they maybe would of even collected some kind of compensation for the taking of our…OUR…natural resources….Someone might of even had an emergency plan in place that maybe might of even….get this,,,,WORKED. But our government no longer represents the people, but the corporation.

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  3. 3. willis 11:06 pm 05/29/2010

    If the bop is instaled corectly, closing in the well should be as simple as cutting off the riser casing, setting a new bop over the casing and bolting to the ring of bolt holes that are allready there( flange) with the bop open, then close and well is shut in. Open when new pipe is attached to cement pump and pump cement into formation not onto sea floor.

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  4. 4. hawkeye 11:40 pm 05/29/2010

    Of course, the sooner they can stop it the better, but it’s already too little too late for the Gulf of Mexico fisheries. The damage that is now occurring will still be evident a hundred years from now. About the only possible good that could come out of it now is if some of the fossil fuel cheerleaders and climate change deniers come to their senses, and realize that we HAVE to change our energy policies; we really have no viable choice.

    Of course, given what I have seen of human stubbornness, I’m skeptical that will occur. More likely, the usual cast of characters will stymie any real reform, and other disasters will occur. Change will only occur when a disaster of truly biblical proportions finally occurs, and desperate measures are required to prevent mass mortality. That may sound unlikely right now, but the course we are on inevitably leads to that conclusion.

    It’s a tragic irony that the species calling itself "Homo sapiens" is not smart enough to foresee the long term consequences of its current decisions.

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  5. 5. shafiulhuq 3:38 am 05/30/2010

    This suggestion to stem the oil flow is from an amateur.
    My suggestion is: Don’t fight the oil gushing out from the sub-sea broken pipe by trying to stop the flow at the rupture point where the pressure is highest. Instead , allow the oil to flow through a large diametre (24"/30") flexible and collapsible, 2-layer canvas pipe , one end of which is lowered over the point of rupture and the other end is tied to one or more buoys..Once oil flow is confined to the canvas pipe, insert two or three 4" HDPE pipe into the canvas pipe to the desired depth and start pumping out the oil+ seawater mixture from out of the canvas pipe onto a barge or platform.
    Shafi Huq

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  6. 6. shafiulhuq 3:53 am 05/30/2010

    This suggestion is from an amateur.
    Instead of fighting the oil pressure at the rupture point by various methods that have been tried out so far, I suggest that the engineers use the same oil pressure to bring up the oil through a large dia(36"-42" ?) , two-layer thick canvas pipe, one end of which is securely placed over the point of rupture and the other end is kept afloat by tying to buoys. HDPE flexible but semi-stiff pipes of appropriate dia to be inserted into the canvas pipes and the oil+water mix to be pumped up.

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  7. 7. Wannabesmart 12:38 pm 05/30/2010

    I agree

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  8. 8. Wannabesmart 12:50 pm 05/30/2010

    This is really getting stupid, it is simple, it my mind, someone please correct me.

    First take a huge tube 3 metre diameter, place over leak, collect oil rising, this shouldn’t be rocket science.

    Then using something similar to the top hat, without a top, place over the leak and drop a few tons of sand first, then stones and pebbles, followed by cement blocks.

    Simply said, put a structure around the leak, fill the structure with enough weight and seal the leak

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  9. 9. rtyui 1:39 pm 05/30/2010

    bp and the government (the president) are handelling this poorly!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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  10. 10. gunondeer 10:37 pm 05/30/2010

    Short of accusing BP Top Management of felonious intent to destroy the industries around the Gulf,for the purpose of forcing the adjacent states to accept royality payments to replace to lost revenues from tourism and fish, I’ like to offer a suggestion. The suggestion is to come up with teflon balloons placed over the well head. The balloons will fill due to the pressure of the gushing oil and with the help of nitrogen, helium injected into the "bags of oil" will rise to the surface for pumpimg into ship. I am talking about really "BIG" balloons-1000′ x. 1000′. As one bag fills another bag is being pumped out….Ron a/k/a gunondeer

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  11. 11. JoeyC 2:24 am 05/31/2010

    Trying to come up with a way to stop the flow must be done taking into account it must be "Macgyvered" with what they currently have in their inventory of parts, because by the time they tooled up to make a new device they’d already have their relief wells dug.

    The problem is though they used poor quality concrete, used unreliable cheap blow out preventers and any moron would of known that it was enevitable that such a disater would occur…that’s anyone. Or let’s put it another way anyone who is in charge of companies that make billions of dollars most likely have people who are not morans who oversea their investments and they knew this would happen, but since they are in bed with our government they knew they’d never pay in the event of an emergency, at least not much, they already knew we would! That is the only logical conclusion one could draw from the facts. Again you could not operate in our gulf under these parameters of operation and not know that there would be a failure.

    So not to have an emergency plan for the enevitable and the correct equipment to handle the job is pure and clear negligence on the part of BP. How can this not be a crime against America?

    Plus since no other oil company came forward with any kind of equipment or tools to help BP we must assume the whole industry in negligent as well. And I believe we must assume that everyone elses wells are just as safe for our enviroment as the last one that failed. So everyone else is guilty of at least breaking the terms of their oil leases.

    I reckon that watching the oil industry keep clean energy industry at bay and helping them to earn billions off our…OUR NATURAL RESOUCES…without us receiving a cent, was obviously well worth the cost of the stupid Gulf of Mexico to our government. Shoot without the oil industry some of ‘em wouldn’t even got elected. And plus two hundered years it’ll be like it never happened.

    To me though it was like destroying a work of art more precious then any Rembrandt or Picasso.

    I feel any politician or government employee involved with allowing the oil industry to do this is guilty of a treasonous act against the the United States of America and needs to be brought to justice. This is government corruption of the most vile and dispicable kind inspired solely by greed without consideration of the good of America, nor it’s people.

    But it took the millions of dollars that BP and the other oil giants have to bribe our politicians that brought this disaster to the American people. The masterminds!

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  12. 12. eco-steve 5:31 am 05/31/2010

    There is an old technique for plugging pipes used by plumbers. Insert a ‘rubber torpedo’ deep into the hole and inflate it with compressed air. Then back fill withh cement and plug it. With a more complicated version, you could even have a ‘pipe in pipe’ to recover the oil flow again. There are companies that specialise in rubber constructions for big industrial applications, so why not give it a go before august?

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  13. 13. Dante09 12:34 pm 05/31/2010

    why aren’t skimmers used to get the oil before it hits the shore ? There are submarines with robotic arms that can go to depths of a mile and deeper. We have to use all resources available because ways of life are being ruined.

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  14. 14. eidnar1 1:32 pm 05/31/2010

    As I suggested in the Physics Forum and to my Senator Tom Udall we should have driven a pipe bomb down the well several hundred feet weeks ago and shattered the the well pipe in a series of explosions. Without a path to the surface the oil would gush into the earth erode a small cavern and then stop. There could be seepage that reaches the gulf floor but nothing sustantial. The problem is everyone is trying to save the oil.

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  15. 15. Shoshin 2:28 pm 05/31/2010


    That’s an idea, but there is oil flowing out at 6000 psi. Trying to stuff anything down there against that flow would be impossible. It would be like stuffing a rubber ballon up a fire hose.

    If they could get a rubber bladder in there, they would stuff a drill string and packer into the well and kill it easily, but they can’t; the flow rates are too high. My best guess is that the second "Top Hat" will also fail and they will end up trying to remove the top flange from the BOP and bolt another BOP on top. This way they can re-enter the well with another drill string and get it under control by pumping mud. Kind of what the top kill should have done if it wasn’t leaking through the riser.

    Or instead, they will remove the flange on the riser, bolt on a gate valve and close the gate valve and fire up the top kill mud pumps again. The know the mud pumps work, but there was too much leakage through the riser.

    Either way it’s an ugly high risk proposition.

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  16. 16. Shoshin 2:38 pm 05/31/2010


    It is impossible to drive anything down the well bore; the flow is too strong. And the last thing that you want to do is explode something in the well bore and create multiple unknown paths for oil to escape. That would guarantee a bigger calamity than what is already there.

    Your views do not reflect how rocks work, oil wells work or production equipment works. Please do us all a favor and not contact any more politicians; you just might find one stupid and desperate enough to run with your ideas.

    Google some information on blowouts that have escaped around the surface casing. One happened in Northern Alberta ca. 1948 and as I recall, it flowed until it died naturally. There was no way to stop it. Massive, massive problem. We don’t want to go there..

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  17. 17. eco-steve 5:46 pm 05/31/2010

    An oil industry specialist on the Reuters website says that there is adequate deepwater machinery available to simply crimp the oleoduct at the wellhead, but BP have so far not taken up the offer. He suggested the vice be left in place permanently….

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  18. 18. eco-steve 5:51 pm 05/31/2010

    Shoshin : Deep water pressure is only a problem when you have hollow apparatus like manned submersibles. Some whales dive nearly as deep as this wellhead to feed, as can they adapt to the extreme conditions very well. And they are soft and floppy…

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  19. 19. Shoshin 9:40 am 06/1/2010


    The problem with plugging the leak as you suggest is not the hydrostatic pressure at the ocean floor. There is still an additional 6000 psi flow coming out of the wellbore that needs to be overcome in order for something to be stuck in there to plug it.

    I haven’t seen a reference to crimping the riser before. Interesting idea though. It may slow flow enough to minimize damage until the relief well is drilled. In a way, that’s kind of what’s happening now. The twists, kinks and bends in the riser are slowing flow.

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  20. 20. eidnar1 11:27 am 06/1/2010

    Shoshin, Where did you get 6000psi. If it really is 6000psi then how dumb was it to hope mud would stop it. As far as the pressure is to strong to force anything down the well, how do think they are forcing mud down the well. If they can drop a 100 ton dome on top the well I think they can apply enough force to drive a pipe down the well with a series of bombs to shatter the pipe. We have the best demolition experts in the world. Blowing the well from deep in the earth would slow this to seepage while we wait for a new well.

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  21. 21. Stephen_Daugherty 2:54 pm 06/1/2010

    And how much structure would be required to support the weight of all that debris against the sides of the container?

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  22. 22. Shoshin 4:57 pm 06/1/2010

    Eidnar 1:

    BP’s has released data that the well has a flowing pressure of 6000 psi. Doing some math, lets assume a 12" opening in the BOP. That gives about 113 sq inches of area X 6000 psi = 678,000 pounds of force or 339 tons. It is plainly obvious from your comments that you have no concept as to how this works.

    Also your comments regarding killing a well with mud indicate that you also have no idea on how that works either. I have been on wells that have kicked gas and almost blown out. The pumping of barite weighted mud pushed the formation fluids back into the formation and prevented the blowout. In most cases, a quantity of barite weighted mud (termed a "pill") is kept on hand in the rig mud tanks for just that type of emergency.

    Think of it this way: A pipe extends 5000′ from the ocean bottom to the top of the BOP. If the pipe is filled with water water (density 1.0) the pressure at the bottom of the pipe will be about 2210 psi. Now, replace that water with barite weighted mud (density 1.6) and the pressure is 3536 psi. To get 6000 psi you would need to force the mud down the wellbore an additional roughly 4000′ after that, the weight of the mud will push the fluids back into the formation with no additional effort; gravity does the job. Using the available 30,000 HP mud pumps, that should have been accomplished easily…. providing that the system didn’t leak.

    But we were not so fortunate.

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  23. 23. marcalpv 5:08 pm 06/1/2010

    @ Bernoulli, you were right in 1783. In an inviscid flow conservation of energy at every point is constant. Pressure and velocity vary inversely, proportional to v**2/2. But not everyone understood you. We have just seen a failed effort by BP to seal the BOP with Top Kill and an added Junk shot where they shot in shaped rubber balls to try to seal the opening from the BOP. The effort failed. They shot the mud and the junk towards the opening. In fact your principle says that if you alter the aggregate density of the column above the lowest point of the bore hole, it would stop the oil flow which I estimate (from other estimates on the web to be 14 ft/sec) You would have advised us to shoot ball bearings towards the bottom. This would stop the small velocity and possibly reverse the flow. At least before the ball bearings reach the bottom of the hole some 13,000 ft away. Then the mud’s density would have had a chance to work.

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  24. 24. marcalpv 5:09 pm 06/1/2010

    @ Bernoulli, you were right in 1783. In an inviscid flow conservation of energy at every point is constant. Pressure and velocity vary inversely, proportional to v**2/2. But not everyone understood you. We have just seen a failed effort by BP to seal the BOP with Top Kill and an added Junk shot where they shot in shaped rubber balls to try to seal the opening from the BOP. The effort failed. They shot the mud and the junk towards the opening. In fact your principle says that if you alter the aggregate density of the column above the lowest point of the bore hole, it would stop the oil flow which I estimate (from other estimates on the web to be 14 ft/sec) You would have advised us to shoot ball bearings towards the bottom. This would stop the small velocity and possibly reverse the flow. At least before the ball bearings reach the bottom of the hole some 13,000 ft away. Then the mud’s density would have had a chance to work.

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  25. 25. eidnar1 10:04 pm 06/1/2010

    So I did a bit of research, not much, but imagination is more important than knowledge. I calculated (just checking) I need the weight of around 8500 ft of sand to equal 6000 psi in a one foot dia. pipe. the relief well is planned to connect at around 12600 ft. not sure how they connect the new well to the original pipe. is that what they do? thats about 7600 ft in the ground. is that where the pipe is broken and tapped. Ok so you are saying I can not feed a pipe bomb down this pipe 7600 ft and rig it to shatter up and down the pipe. I have not studied the actual earth leak resistance in the face of 6000 psi at 12600ft, but once a cavity has eroded by the flow after the initial explosion what is the objection. Are you saying that i do not understand rocks means there are fissures that would provide an immeadiate path to the surface? how deep do you have to be before you could seal off the leak considering you have shattered the well pipe and eliminated the straight pipe line to the surface. If I understand it right the top kill was only to fill the blowout preventer with sand and that was a very short distance of sand to hold back 6000psi of oil. still trying to make sense of why they picked that deep. is it because when your that deep it does not matter how you much it leaks when you tap the orginal pipe?

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  26. 26. marcalpv 10:48 pm 06/1/2010

    @ Ednar1 and Shosin, I think the 6000 psi refers to the pressure at the bottom of the well hole. The differential pressure at the exit from the BOP is only sufficient to cause a flow velocity of 14 ft/sec. The rest of the bore bottom pressure goes to supporting the column of oil. The problem of Top kill is that it depended on building up a differential pressure by pumping mud through a 3ins. diameter pipe to overcome the escape through a larger BOP exit hole. A simple Navier Stokes analysis would have told them if it would have worked for this particular situation. As I implied in my comment they would have been much better off stuffing ball bearings down the bore hole, that would have reversed the flow. BTW if you go to home page of my web-site you can download an analysis I made of crimping the riser. I think that the reason they are drilling the second hole that deep is that if they miss the hole they can carry on to the bottom and relief the pressure on the first hole by pumping oil from the second.

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  27. 27. Shoshin 1:30 pm 06/2/2010


    No, you will not be able to stuff a pipe bomb down the hole. I should have clarified issues a bit more, but I was in a hurry. There are several different pressures, as marcalpv pointed out that come into play. There is a Bottom hole pressure (BHP) a Flowing pressure FP and a Well Head Pressure WHP. The BHP is likely around 8000 psi, assuming hydrostatic, but from what I understand the pressure may actually be quite a bit higher than that as you must add in lithostatic pressures, not just hydrostatic. The FP is the pressure that the oil is actually flowing at. The WHP is what the pressure at the BOP would build to if the well was shut in, which in this case is the 6000 psi. As you start to stuff your pipe bomb in there, the flow will constrict and the pressure would build, possibly reaching the 6000 psi.

    But it is all a moot point. If BP could stuff a pipe bomb in there, they would be able to in a well control device called a "packer" and the well would be killed in minutes, no fuss, no muss no bother. No risk of an explosion and the unpredictability that that entails.

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