Monday, June 19, 2017

Not a good picture

I think it would have been better if this
picture were never taken?
Credit: Washington Post
Alarms were sounded more loudly after a nuclear technician positioned eight plutonium rods dangerously close together inside what is called a glovebox — a sealed container meant to contain the cancer-causing plutonium particles — on the afternoon of Aug. 11, 2011, to take a photograph for senior managers. Doing so posed the risk that neutrons emitted routinely by the metal in the rods would collide with the atoms of other particles, causing them to fission enough to provoke more collisions and begin an uncontrolled chain reaction of atom splitting. 
As luck had it, a supervisor returned from her lunch break and noticed the dangerous configuration. But she then ordered the technician to reach into the box and move the rods apart, and a more senior lab official ordered others present to keep working. Both decisions increased, rather than diminished, the likelihood of an accident, because bodies — and even hands — contain water that can reflect and slow the neutrons, increasing the likelihood of a criticality and its resulting radiation burst.
It sounds like there are all sorts of issues at LANL's production facilities, including a relative shortage of engineers trained in criticality calculations:
A February report by the Defense Nuclear Facilities Safety Board, an independent safety advisory group chartered by Congress, detailed the magnitude of the gap. It said Los Alamos needs 27 fully qualified safety engineers specialized in keeping the plutonium from fissioning out of control. The lab has 10. 
Some of the reports obtained by the Center for Public Integrity described flimsy workplace safety policies that left workers ignorant of proper procedures as well as incidents where plutonium was packed hundreds of times into dangerously close quarters or without the shielding needed to block a serious accident. The safety risks at the Los Alamos plutonium facility, which is known as PF-4, were alarmingly highlighted in August 2011, when a “criticality accident,” as it’s known, was narrowly averted, one of several factors prompting many safety officials there to quit. 
Well, just as long as things are all right over there...  (that first story has echoes of Louis Slotin...)

UPDATE: Added some clarifying language. 

17 comments:

  1. This is no surprise. There are some pretty lackluster scientists working at National Labs. The primary objective of these places is to protect what they have.

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    1. Every institution has a distribution of human capital. That said, this type of error is likely technician training and administrative/engineering control related. Honestly, scientist at the National Labs are too busy chasing funding to be directly involved in criticality incidents. PF-4 may have its issues, but keep in mind it is the only plutonium manufacturing facility in the USA, and is inherently an operation that doesn't privatize.

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    2. Vrampire: A total of 15 Nobel Prizes have come from research in federal research labs, but somehow I doubt your opinion would change even if that number were doubled. The fact that Los Alamos (and other labs) are managed by LLCs that accept multi-billion dollar contracts in exchange for precious little in the way of actual management doesn't even enter into your thinking, I reckon.

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    3. My direct experience is the basis for my evaluation. I observed no hard-working, brilliant scientists on the staff. Just lazy people who stayed out of the labs and only thought about themselves and their friends.

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    4. I work in a national lab with a ton of smart, motivated people. Anecdote for anecdote.

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    5. Ok, Anonymous. Sorry if a whole research center of mediocre, unprofessional, underperforming scientists tarnishes the reputation of high quality government scientists elsewhere.

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  2. That is not a good picture, for sure. But, when the supervisor ordered the technician to "reach into the box" to move the rods apart did they open the Glove box and use their bare hands, or more probably, use the gloves in the glove box? The article seemed to suggest they opened the glove box and used their hands (by the comment about water on hands).

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    1. I'd strongly believe it would be access via the containment-maintaining gloves. The water neutron reflector portion would be regarding the water in the people working in the area, not necessarily that one was reaching in with wet hands. It's still pretty wild to me to think about the water mass of people leading to criticality excursions.

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  3. What's preventing the hiring of additional safety engineers?

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    1. The federal budget

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    2. Money should be readily available. After all, this is not for frivolous programs like healthcare or enforcement of job-killing environmatal regulations. This is to defense ( D ##!).

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    3. In the President's budget request NNSA (which is what funds most of LANL & especially the mission-related stuff like PF-4) gets I think an 11% increase, that funnels down to NNSA labs like LANL pretty much 1:1. Even assuming that's not what the final budget looks like for the next fiscal year, or of we're just operating under a continuing budget resolution (likely outcome), it seems unlikely that the federal budget would be the key issue for an NNSA program doing hiring.

      The deal is that the operation of LANL & all the other national labs is contracted out to various LLCs. Those LLCs then sub-contract to others for some operational parameters as the WP article notes. The profit of those sub-contractors is directly tied to timely production of mission deliverables both in terms of bonuses and regular operating profit. You can see that this setup really doesn't align short-term goals with long-term operational safety very well. There's also the issue that there aren't all that many fully qualified nuclear safety engineers with Q-clearance floating around, so if you've alienated a substantial subset of them already, it's going to be a problem.

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  4. $2M is a lot of startup at any school. Certainly it has happened, but this is not routine.

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  5. First time reading about the Slotin accident, pretty fascinating and also very dreadful.

    "At 3:20 p.m., the screwdriver slipped and the upper beryllium hemisphere fell, causing a "prompt critical" reaction and a burst of hard radiation.[8] At the time, the scientists in the room observed the blue glow of air ionization and felt a heat wave. Slotin experienced a sour taste in his mouth and an intense burning sensation in his left hand. He jerked his left hand upward, lifting the upper beryllium hemisphere and dropping it to the floor, ending the reaction."

    "Over the next nine days, Slotin suffered an "agonizing sequence of radiation-induced traumas", including severe diarrhea, reduced urine output, swollen hands, erythema, "massive blisters on his hands and forearms", intestinal paralysis, and gangrene. He had internal radiation burns throughout his body, which one medical expert described as a “three-dimensional sunburn.”"

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  6. Los Alamos, like all DOE facilities, has incident incident reporting and investigation in their integrated safety management systems. From the news article, it is unclear if this picture resulted in a non-conformance and/or investigation, though I suspect that it did. From my perspective, the important take-away from the article is to highlight the management-safety interaction (or apparent dysfunction) and how that inevitably translated into a safety stand-down; and even then management gets the report "management has not yet fully embraced its commitment to criticality safety." Ouch.

    The news article highlights that avoiding a criticality incident is "complex" and not intuitive. I tend to disagree with that assessment: Criticality boils down to (1) critical mass - which will include neutron flux from spontaneous fission, and "form" and (2) critical geometry - which includes shape and geometric configuration and presence of neutron reflection back into the mass. The closer you get to a critical mass, the higher the overall risk. The closer to critical geometry (primarily spheres and cylinders), the higher the overall risk. Risk can be mitigated by reducing mass to well below the critical mass, placing masses far apart (reducing the likelihood of neutron interaction with fissionable material), adding neutron absorbing material between the masses (like highly borated polymers). It's not "that" difficult, but it does take effort and short-cutting the process can lead to a bad day. There are seldom "do-overs" in criticality incidents.

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  7. This didn't miss by much. A solid sphere of Pu-239 4 inches in diameter is the threshold for prompt criticality. Looks like there was more than enough fissile material, and it was only geometry and the absence of moderator or reflector. I'm sure Los Alamos has software for calculating how many cents (actual unit) they were away from cricality with this assembly. I can't imagine how bad this would have been in a laboratory environment.

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  8. There are a number of laboratory-scale and slightly larger than lab-scale criticality incidents. None of them turned out to be a good day for any involved. My personal favorite (as it has a boat-load of lessons learned in it) is the 1958 Kelley incident at LANL involving a 1000 L waste tank that Kelley thought contained less than a critical mass. When he turned on a stirrer, the tank went supercritical. He received about 3600 R in dose and died about a day and a half after the incident.

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