Guest Post: Oil Pressure Stopping Short of Target … Does that Mean the Well Integrity Test Is Failing?

Washington’s Blog

The well integrity test is arguably failing, as the pressures are not reaching the 8,000 psi minimum target.

CBS News notes:

The federal pointman for the BP oil spill says results are short of ideal in the new cap but the oil will stay shut in for another 6 hours at least.

Retired Coast Guard Adm. Thad Allen said on a Friday afternoon conference that pressure readings from the cap have not reached the level that would show there are no other leaks in the well.

He said the test will go ahead for another 6-hour period before being reassessed to see if BP needs to reopen the cap and let oil spill out again.

MSNBC writes:

Allen said two possible reasons were being debated by scientists: The reservoir that is the source of the oil could be running lower than expected three months into the spill. Or there could be an undiscovered leak somewhere down in the well.

The New York Times reports:

Thad W. Allen, the retired Coast Guard admiral who is overseeing the response to the gulf oil spill, said that while there were indications from the test that the well was in good shape, it was not yet possible to rule out damage that could complicate efforts to halt the leak permanently.

“We want to be careful not to do any harm or create a situation that could not be reversed,” he said in a conference call with reporters Friday afternoon.


Admiral Allen said the test would continue in six-hour increments and that any new data would be reviewed by scientists and engineers from the government, BP and other companies. He said there would be “enhanced monitoring” of the seabed, including acoustic tests that could detect tiny bubbles of methane gas coming from the bed, which would be evidence of damage to the well.


Admiral Allen said that such a pressure buildup suggested that the well was not damaged. But he said that the pressure level reached — about 6,700 pounds per square inch, or more than 450 times atmospheric pressure — was below that expected for an intact well.

One explanation for the ambiguity, he said, is that the reservoir of oil 13,000 feet below the seabed could have been depleted by the well as it galloped out of control for nearly three months. But another possibility is that the well is breached, with oil and gas escaping into the rock or, worse, into the gulf through the sea floor.

BP states that the pressure in the well is only rising 2 pounds per square inch each hour.

I will post a transcript of Allen’s report when it becomes available (here is an unofficial, rough transcript). In the meantime, blogger Wang – who attended the press conference by telephone – added details from Allen’s press conference (I simply edited for clarity of reading; I will update with corrected and expanded transcript as I receive it):

Uncertainty about the meaning of the pressure. Could be lower because of well integrity, or the reservoir has become somewhat depleted and so is lower in pressure than expected.

The initial curve of pressure build up was normal but stopped short of our target which is the concern.
Don’t want to create harm or an irreversible situation.

Was the reservoir depleted or is there an ongoing way for the oil to leave the well bore? We do not know the condition of the well bore. There’s a good chance it could be depletion. Checking out the well bore. Checking for leaks. We have no indication of a seafloor breach so it could be reservoir depletion.

Additional seismic surveys are required.

This kind of formation can maybe heal itself if we do damage it, the quickest way to reduce pressure is opening the kill and choke line.If there is a problem we will vent the oil.

Reservoir depletion can be measured by determining if there was an aquifer beneath the reservoir but there is not one. If the seismic and acoustic show no sign of leakage we will continue with the testing.

NOAA boat looking for methane from the sea floor with acoustic device. There is some concern about methane. We want to make sure there is no methane. If we were to detect methane we would lower the pressure by venting or ramp up Helix Producer.

We will reevaluate in 6 hours and have a series of meetings (with the committee) everything moving forward is condition based. We should have results in the next 6 hours. The 6 hour period starts now.

(BP’s Kent Wells gave a similar, follow-up briefing.)

There are actually at least four potential explanations for the low pressure readings:

(1) There are substantial leaks in the well;

(2) There is leakage in the sands deep under the seafloor. Oil industry professionals posting at the Oil Drum hypothesize:

What this could indicate is that there is a possibility of crossflow at the bottom of the well. What this means that the oil and gas that are flowing out of the reservoir into the bottom of the well, are, under the pressure in the well, now flowing into a higher reservoir of rock, now that they can’t get out of the well. Depending on where that re-injection flow is, this may, or may not, suggest that the casing has lost integrity. This is a topic that has been covered in the comments at The Oil Drum, where fdoleza – “a petroleum engineering consultant retired from a major multi-national oil company” – has noted:

… I believe the flow will be coming out of the bottom sand and going into the upper sand. It would not be a leak, but it would tell them why their pressure data ain’t a classical surface buildup. And I sure hope they’re modeling temperatures and so on, because this is a very interesting case. They don’t have downhole gauges, so they’ll have to take the way the oil cools down as it sits to get a better idea of the way things are moving down below.

If there are questions whether there is still flow in the formation or from the original formation into surrounding rock, then it is possible that the relief well (RW) is close enough to the original well (WW) that putting a set of very sensitive microphones down the RW might allow some triangulation to estimate where such a flow might be occurring. It might make it easier that the well hasn’t been finally cased yet. But the test has 2 days to run, and will be evaluated every 6 hours. With time some of these questions may be answered as the test continues. (If there is no flow anywhere, after a while all the readings should become quite stable).

(3) A hypothesis proposed by Roger N. Anderson – professor of marine geology and geophysics at Columbia University – that the pressure could be rising slowly not because of a leak, but because of some kind of blockage in the well: “If it’s rising slowly, that means the pipe’s integrity’s still there. It’s just getting around obstacles”


(4) The reservoir has been depleted more than engineers anticipated (although many experts have said that the reservoir is much bigger than BP has forecast; in any event, there are factors other than size which determine pressure. For example, blowouts can reduce pressure pretty quickly in some reservoirs)

While many oil industry experts are betting on damage to the well bore or communication between layers of sand, Don Van Nieuwenhuise – Director of the Professional Geoscience Programs at the University of Houston – thinks reservoir pressure has simply “deflated”, and that 6,700 psi isn’t unexpected:

The 6,700 pound- per-square inch pressure reading logged inside the blown-out Macondo well this morning may suggest that the well has lost power over the almost three-month-long period it has flowed into the Gulf of Mexico and not that the well is leaking somewhere beneath the sea floor, a geologist who has been following the gusher said.

The reservoir could have “deflated” since it began leaking April 20, reducing the amount of pressure it is capable of producing, said [Van Nieuwenhuise].


But Van Nieuwenhuise said this morning’s 6,700 pounds per square inch reading should not cause worry.”I don’t think it’s a cause for immediate concern, because it could reflect a natural loss of oil in the reservoir,” Van Nieuwenhuise said. “It’s amazing that it has held its strength for as long as it has.”


When they first said this, I said if they can get to 7,000 (pounds per square inch) that would be good,” Van Nieuwenhuise said. “The 8,000 to 9,000 estimate reflects its initial pressure, but since it’s been bleeding so much, I’m not surprised it’s at 7,000.”

Note 1: Because pressures are still rising (if only 2 lbs per hour), it probably means that the well integrity test hasn’t caused any new leaks so far.

Note 2: Oil industry expert Robert Cavner notes that seismic testing isn’t as straightforward as it sounds:

Seismic puts sound into the sea floor, and measures the time it takes for those sound waves to return. Different kinds of rocks reflect sound waves at certain velocities, or speeds. By measuring the time it takes for the sound to return from a certain depth of rock, geo-scientists can draw maps of the subsurface. Often you can get an idea of the fluid within the pore space of rocks by the way it returns sound waves. They ran a baseline survey a couple of days ago, and will compare that data to the data that they’ll get today to see if anything has changed around the well to indicate fluid movement. But, as one of my geologist friends of mine likes to say, reading seismic for precise conclusions is often like trying to observe airplanes flying overhead while lying on the bottom of a swimming pool. It’s difficult to draw definite conclusions, even using high frequency seismic, but it will be another data point.

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George Washington is the head writer at Washington’s Blog. A busy professional and former adjunct professor, George’s insatiable curiousity causes him to write on a wide variety of topics, including economics, finance, the environment and politics. For further details, ask Keith Alexander…


  1. Dwight Baker


    Too quote the New York Times – AP– ABC, NBC, MSNBC, FOX News and others is like getting in touch with some sitting under a bridge getting drunk and ask them about DC Politics.

  2. Dwight Baker

    BP BS has grown to new heights where common language does not work any longer and gone far below into the abyss in actions done absent of intellect with intent to deceive.
    By Dwight Baker
    7/17/2010 2:08 AM

    Amid the growing disparity in our Rich and Abundant Gulf the dim glowing embers of a people totally forgotten is getting worse by the minute — each time the clock ticks. Yet our own people have bought into the BP BS insanity now most are being quoted as using BP BS rhetoric as some kind or sort truth filled report. And to state it simply no one has got a clue of what the hell is really going on except for a few of us who do.

    Many have forgotten the Gulf oil belongs to We the People. BP pays us royalties to produce our oil. How much and when and are those numbers real or fraudulent and who ends up with the pile of money our properties produce WHO KNOWS. I am sure some under the control of our President could read those numbers to us, if they were demanded to do so. But there is another rub under our saddles for those that know ain’t telling.

    So just using common horse sense about what is what and what is not we must asks one another who has the slightest clue of what that is being said is the TRUTH. Maybe in America the number might be about ten or maybe twenty.

    I have known the truth all along and I paid the price of study to get there. I did not accept any BP BS when I had heard enough lies that told me not too. BP has been running rough shod over us for some time, notably the Thunder Horse sitting dead in the water for months on end while the BP SPIN MASTERS keep it out of the news. To many things that have gone wrong that cast a doubt on the honesty of BP for me but maybe not you.

    And even with the seemed good reports of BP holding tight all the gas and oil coming out of the Macondo well I still believe there are lies behind those stories. Too much at stake politically for President Obama for the total truth to come out.

    Now with all the mum boo jumbo of the pressures going up and down and could there be a break in the well casing or such be the reason for it. I put no stock in those BP BS LIES.

    Let us just imagine that BP LIES! Then lets imagine that some of the giant ships sitting around have huge storage tanks aboard that can pump up some oil and gas and store. Would that be a good reason we see the pressure go up and down? Then to go on just in an intelligent way to problem solve as good detectives should do, would BP be better off to know for a fact how much pressure their connection on the bottom of their stack attack and the BOP take before leaking. Then in some devious way bleed off the excess pressure to the holding tanks of ships to once again deceive We the Public that they finally got it right?

    Now how can a thesis like that be proved to be right or wrong? Forget about it. BP HOLDS ALL THE KEYS TO THEIR LITTLE IMPERVIOUS KINGDOMS OF DECEIT. Our own Coast Guard as the law of the land and sea enforces all the BP rules and regulations.

    Some and maybe many might say OH GOSH could that be true? Then a good come back would be WAKE UP AMERICAN PEOPLE WE HAVE THE PREEMINENT MONSTERS AND MOST DEVIOUS OIL PRODUCER IN OUR BACKYARD KILLING OUR GULF. And they are protected from the top to the bottom by our own elected ones governing.

  3. Dwight Baker

    Passion to resist is often not seen or heard
    For no need too
    Many run from what they perceive to be a lost cause.
    By Dwight Baker
    7/17/2010 6:29 AM

    I suggest for intelligent discussion and leading to personal discovery that BP has been lying all along about their new cap attack.
    I have been the very best advocate for our Gulf region than any other bar none.

    Case in Point: On May 13, 2010 I had worked through the solution of plugging the Macondo Well for good taking only 3 to 4 days to do. I sent that along to BP investor relations in Britain so that it could then be passed along to the BIG BP BRASS.

    My plan to cap then plug the well in one simple operation was and is the easiest and most efficient way to get it done.

    After over 400 hours of intense study reading over 100,000 words of engineering oil and gas information of the problems existing, maps of geologic formations, casing string runs, down hole drilling and production techniques used up to the time, I was dead set on the plan called Tame Nature with an overshot.

    Then with BP continuing to do stupid idiotic stuff and telling all that the relief wells would fix the problem, I resisted again because what they were telling was a bold face lie. [Essay to follow]

    The plans had been worked out between Boots and Coots owned by Halliburton and Halliburton pumping folks to pump in cross linked gelled [glue] particles to bond with the flowing up of oil and gas to cause a plug up above the entry point of the bit into the old hole. Thus plugging the well.

    Yet that was never to be done for the pump rate by Halliburton could not come close to over come the open flow rate of the oil and gas flowing from the over 1300 feet of open hole Wilcox permeable formation. [Essay to follow]

    Then up jumped out of the dark dredges of BP NON oil and gas engineering come this new twist to BP old game called deceit. Their new CAP ATTACK [my name because it befits their ignorance] was shown to be the cure in all ways to do very simple things that only they could do and oversee because of the suspected down hole problems.

    NOW STOP FOR A BIT AND RE-READ. There has never been a down hole problem except for one—- four high ranking BP employees did four bad things in a row and caused the well to blow out. Simple as one two three. But BP is still out to try to confuse those basic facts to run from the money issue liabilities that lay out against them for maybe a century of time or even more.

    Now to get back to WHY and how they are saying now the well has been shut down, better run from that one two. Remember BP LIES.

    It finally occurred to BP that they must try to PLAN A CAP ATTACK TO slow down the flow so that the cross-linked gelled particles could have a chance to set up in the flow to retard. The when doing Halliburton could begin pumping [whatever] into the 1300 foot of formation to plug. Might sound good to some but that is stupid too. Doug Suttles BP BOSS AT THIS TIME said on TV that the entire open hole formation would be cemented—- hello what a non-oil and gas engineer that clown is. Try to imagine pumping cement for four weeks!!!!!! Cement sets up regardless of what one does to retard. Suttles is an idiot and that is that. He like all the others we have seen and heard from BP is just goons put before the press to try to duck and deceive.

    So now lets go back to my original sure cure for the blown out well and lets see if BP tried to steal my innovations in products and process’s, my patents applied for at this time. My plan was to set on top of the BOP an overshot with rubber goods in the bottom to make the seal that BP is supposed to have now, with 7-inch casing from the Mother Ship loaded with heavy weight mud and loss circulation material weighing from 400 to 500 thousand pounds then after setting in place burst our pump out plugs in the bottom of the casing string and send the tame nature violent blast of that material down against the flowing oil and gas then follow up with pump pressures and volumes able to continue pushing the oil and gas back into the formation.

    After pumping pressure began to rise suitable to know that the process was well under control then pump 3,000 feet of cement to set up in the primary casing string below the BOP.

    Simple oil and gas engineering plan and beats the hell out of drilling relief well holes but BP in their magic of doing things the wrong way and out of sorts with common sense and reason shirked away and today they have solely caused to bear on our people and Gulf in total 65 days of gross negligence induced genocide that will only be seen in the up and coming generations and the deaths that follow due to the air borne toxins breathed in and the skin infections that now have gone inside blood streams to kill slowly , and in the end the final blow the ruination of our Gulf of Mexico.

    Public opinion around the world is ageist BP in all ways. And President Obama is right in the scope of the investigations too for he held in his hand as our CEO the ability to take out BP appoint good folks and he did not. Instead the ones sent to pier review just picked up their BP SCRIPT and stayed between the lines. And many of our big boss folks in DC flew over many times, no way were they going to get caught in all the muck and gooo in the air and floating in places that our own Coast Guard had put on a no visit zone by anyone. Go figure that.

    So what is in final storehouse for BP TO DO, to right the wrongs and get with the program —- get with me buy the Tame Nature Plan and finish the blown out well in 3 to 4 days.

  4. Anonymous

    Suppose Matt Simmons is correct that there is another hole miles away that is larger, bigger, and spewing more oil into the GOM.

    That would lend credence to how much pressure could have dropped so much so fast (to a peak of 6,700 PSI) and raise doubt as to whether the wellbore / wellhead they are working on is compromised.

    The real question is, does a second, larger leak miles away exist?!

    If such a leak truly exist and have been concealed from the public, when it is revealed – there will be retribution that no amount of politics and bribery can save BP.

  5. Al Fin

    Nice overview. Pressure is not falling. Pressure is rising slowly. It needs watching.

    Some of the commenters so very angry at BP might consider how they would proceed if the oil company involved had been a sovereign national company from Venezuela or Russia?

    Ironic that now that BP is more experienced than other companies at dealing with this kind of catastrophe, everyone is out to destroy the company totally. Presumably this is to allow inexperienced oil companies to go through the same learning curve — before destroying them in turn.

    1. Bernard

      yeah imagine that. putting out of businesses those that don’t work! what an idea!!! capitalism is truly weird.

  6. Fog Horn Leg Horn

    “Ironic that now that BP is more experienced than other companies at dealing with this kind of catastrophe, everyone is out to destroy the company totally. Presumably this is to allow inexperienced oil companies to go through the same learning curve — before destroying them in turn.”

    What the fuck does it matter how “experienced” you are in oil field production if you still cut corners and shave costs to run the mother-of-all risks and destroy the Coast in the process? Seems to me that perhaps those less experienced wouldn’t behave like the cowboys that have ruined my home.

  7. Neil D

    My goodness I hope it works so the clean up can really begin. As an aside, it will also mean all the professional conspiracy theorists will be proven wrong and the world did not end.

    It never does, you know, end. The world… Hasn’t ended yet.

  8. Bernard

    when i grew up a slogan i remember was “Better Living through Chemistry.”

    Nowadays i don’t believe in either the Government or in Business, since they are now one and the same. lol

    Member when St. Ronnie said the “government is the Problem, nowadays that also applies to Business. Business runs Government as the BP incident shows.

    there is no difference between what BP wants and what US Coast Guard Admiral Allen does. Truth!! where? yea sure!! lol.

    the Republicans got Business to takeover Government, and boy, does Government suck or what!!! lol proof positive about some old adages.

Comments are closed.