Jeffrey LewisDas Puffen Boomer

On Thursday and Friday, I attended a workshop sponsored by AAAS and Princeton concerning advances in Comprehensive Nuclear Test Ban Treaty monitoring and verification. There was considerable discussion of “venting” — when underground nuclear tests eject radioactive material into the atmosphere — as a detection method.

There were frequent, grim jokes about BANEBERRY, the worst radioactive venting incident in US testing history (pictured above). Here is a brief description from the Office of Technology Assessment (1988):

The exact cause of the 1970 Baneberry venting still remains a mystery. The original explanation postulated the existence of an undetected water table. It assumed that the high temperatures of the explosion produced steam that vented to the surface. Later analysis, however, discredited this explanation and proposed an alternative scenario based on three geologic features of the Baneberry site: water-saturated clay, a buried scarp of hard rock, and a nearby fault. It is thought that the weak, water-saturated clay was unable to support the containment structure: the hard scarp strongly reflected back the energy of the explosion increasing its force; and the nearby fault provided a pathway that gases could travel along. All three of these features seem to have contributed to the venting.

In this context, some participants mentioned a fantastic report, Caging the Dragon: The Containment of Underground Nuclear Explosions (1995). My crack staff managed to track down a copy. To my delight, I discovered that some wag, presumably reflecting on BANEBERRY, included this cartoon in the front-matter:

It’s on page iii in the front matter. The piece is signed with an interlocking D and L. None of the authors or those interviewed for the book have the initials DL (or LD for that matter). The author of the book, however, was the late James Carothers who served as Division Leader of L Division at Livermore around the time of the BANEBARRY venting.

As circumstantial evidence and conjecture goes, that’s at least as good as Reed and Stillman’s id of Perseus.


  1. Kirk

    Remember, venting can come in several ways, not just the dynamic type seen in this figure, but radioactive xenon can also vent.

    It turns out that the use of radioactive xenon is the main way to verify that an explosion was nuclear.

  2. Allen Thomson (History)

    Somewhat off the subject, but I wonder how determines its pricing:

    ProductType: Technical report
    NTIS Order Number: DE98000017

    Caging the Dragon: The Containment of Underground Nuclear Explosions

    Please select a media type!
    $55.00-Electronic Document [PDF]
    $70.00-Customized CD
    $137.00-Print on Demand

  3. cosmicRay

    Is it just me or do other people see a wolf in that mushroom cloud?

  4. rkelly (History)

    You can get a copy of Caging the Dragon by going to:

    & sign up for a free acct.
    Log in & do a search for the document & download the pdf.

  5. Josh (History)

    “Shredded containment reports.” That’s a nice touch.

  6. Yale Simkin
  7. Major Lemon (History)

    Venting hot air is not only the reserve of nukes, but also the bad guys who want to make them. Observe for instance yesterday (20th April) Fuhrer #2: Ein Reich, Ein Volk, Ein Dinnerjacket.

  8. rkelly (History)

    A direct link to Caging the Dragon: The Containment of Underground Nuclear Explosions

    — Yale Simkin · Apr 21, 09:45 AM ·

    I think that’s a different report than Jeffery’s reference.

  9. J House (History)

    That is one nasty genie coming out of the bottle.

    Does anyone know where on the NTS the shot took place? (or have geo coord)?
    I recall in my tour the discussion about it and the efforts to monitor other groundwater sources at NTS afterwards

    It does look like a wolf…with a marge simpson hairdo

  10. Jeffrey Lewis (History)

    It is, actually, a different report.

  11. rkelly (History)

    “Does anyone know where on the NTS the shot took place?”

    Area 8
    Hole U8D
    Lat: 37.173
    Long: 116.100

  12. Yale Simkin

    By George, it is a different report – but a nice one nonetheless…

    In another interesting piece by Brownlee on the Pascal-B “(non-)Space Launch” found at the outstanding Nuclear Weapon Archive
    Learning to Contain Underground Nuclear Explosions

    By Dr. Robert R. Brownlee
    June 2002
    Sometime in 1956 Dr. Alvin Graves, Division Leader of the Test Division at Los Alamos told me that we were going to have to test underground in order to reduce fallout as much as possible. He asked me to see what I could learn about it by making what calculations I could.

    The temperatures and pressures generated by a nuclear explosion are such that there was considerable doubt that any underground test buried at a “reasonable” depth could be contained.

    In 1956 we were severely limited in computing capabilities-compared to nowadays they were laughable, and miniscule, and arguably nonexistent. I had the equations of state of four materials. They were air and water, aluminum and uranium. As it happens, there is a lot of aluminum in NTS soil, so I called that “earth”. I called that of uranium “fire”, and the others were air and water, so with earth, air, fire and water, how could I fail?

    In attempting to mock up the earth, I had some information about NTS soil densities and water content. I used a cylindrical pipe filled with air of several densities, depending upon the possible use of vacuums. I was allowed considerable freedom to choose other parameters as I wished. For example, what might the efficacy of plugs of various masses be, and where might they be placed for optimum results. I worked regularly with Bill Ogle, the deputy division leader, and we decided to have a first test in an “empty” pipe (cables were present), open at the top. Then we would do a test with a cap, and then do tests with plugs, the first one used to be in the middle of the hole, and the second one at the bottom. Thus we hoped to learn from test to test, acquiring data and information incrementally. Incidentally, the Pascal B test, and those immediately following, had a 4-foot diameter pipe. The cap welded to the top of Pascal B was four inches thick, so was of appreciable mass from a “man-handling” point of view.

    The first test of our “series” was Pascal A, with results as documented.

    For Pascal B, my calculations were designed to calculate the time and specifics of the shock wave as it reached the cap. I used yields both expected and exaggerated in my calculations, but significant ones. When I described my results to Bill Ogle, the conversation went something like this.

    Ogle: “What time does the shock arrive at the top of the pipe?”
    RRB: “Thirty one milliseconds.”
    Ogle: “And what happens?”
    RRB: “The shock reflects back down the hole, but the pressures and temperatures are such that the welded cap is bound to come off the hole.”
    Ogle: “How fast does it go?”
    RRB: “My calculations are irrelevant on this point. They are only valid in speaking of the shock reflection.”
    Ogle: “How fast did it go?”
    RRB: “Those numbers are meaningless. I have only a vacuum above the cap. No air, no gravity, no real material strengths in the iron cap. Effectively the cap is just loose, traveling through meaningless space.”
    Ogle: And how fast is it going?”

    This last question was more of a shout. Bill liked to have a direct answer to each one of his questions.
    RRB: “Six times the escape velocity from the earth.”

    Bill was quite delighted with the answer, for he had never before heard a velocity given in terms of the escape velocity from the earth! There was much laughter, and the legend was now born, for Bill loved to report to anybody who cared to listen about Brownlee’s units of velocity. He says the cap would escape the earth. (But of course we did not believe that would ever happen.)

    The next obvious decision was made. We’ll put a high-speed movie camera looking at the cap, and see if we can measure the departure velocity.

    In the event, the cap appeared above the hole in one frame only, so there was no direct velocity measurement. A lower limit could be calculated by considering the time between frames (and I don’t remember what that was), but my summary of the situation was that when last seen, it was “going like a bat!!”

    As usual, the facts never can catch up with the legend, so I am occasionally credited with launching a “man-hole cover” into space, and I am also vilified for being so stupid as not to understand masses and aerodynamics, etc, etc, and border on being a criminal for making such a claim.

    I’ll add that we learned a lot with our series of low-yield tests. Plugs helped, but the closer to the nuclear device, the better. “Tamping” the device is better yet, and there are some ways to do that which are more clever than others. Mostly we learned that even an empty hole could cause a reduction to the atmosphere of as much as 90 percent, depending on specific design parameters. Later we were to see that if the hole is deep enough and the yield is high enough, an empty hole will close completely, allowing nothing whatsoever out except the initial light, which is not radioactive of course. In time, the tests became very sophisticated-and expensive, but we were able to achieve complete containment for almost every test, and for all but a handful of those that had containment “failures”, nothing was detected off site. So I would judge our containment efforts to be quite successful. The case for these views are pretty well laid out in the book Caging the Dragon, by Carothers.

    But it took time and money!

  13. Carey Sublette

    “Caging the Dragon” used to be available at:

    It seems though to have done a disappearing act. No OSTI search I do brings it up now.

    But not to worry! I have placed a copy on my website for downloading:

    It is 40 MB, so it may take a little while.

  14. mike (History)

    DL = Don Linger

    Head of the test directorate at DNA.