LS-1 Nuclear Facility

Factual Questions
1

I was watching History’s Mysteries tonight on the History Channel, and they had a story about the LS-1 Facility that had a reactor leak in 1961. I’d never heard of it before, but apparently there were 3 men working the reactor. One of them was hurled up into the ceiling of the main reactor room, I believe, and was impaled upon a metal rod. They didn’t specify exactly what happened to him, and if any-one knows, I’d love to be informed. Also, if any-one knows of any pictures/archives showing said person and/or any-thing about the LS-1 facility I’d love to know.

justin
(not trying to be too morbid hehe)

2

I get to be scary morbid!!

Back when I was a baby Nuc, the Navy slammed this one home hard, that we (the Nav) would never do something like this ourselves…

OK, first a little background:
The US Army wanted in on the nuclear game, back when no one knew just how hairy it could get, and the only realistic use they could find for nuclear power was semi-perminent power plants for remote bases (not a bad idea, conceptually…). They came up with a design that would use a pre-fab parts for the reactor and related buildings, and use local materials (dirt, gravel, etc) for shielding. OK, so far, so good.

Now having designed and set-up the prototype, the trouble starts: The Army sent their reactor technicians through a “rigorous” training program, measuring just a couple months long (rigorous? NOT! The Navy takes about two years to make a Nuc). This was in no way sufficient to properly train the techs. Next, the design had a couple of critical flaws: First , the reactor could go critical (“critical” is a self-sustaining chain reaction: The point where the reactor is actually starting to ‘work’) when only one control rod was pulled, and it would go critical before that rod was withdrawn more than about a foot. Worse, the reactor could go “prompt-critical” when only one rod was pulled to about 1 1/2 feet. Prompt-critical is a VERY BAD THING, leading to uncontrolled power excursions (think steam explosion, destroyed instrumentation, etc: BOOM). Second, the reactor need to have it’s control rods manually operated to perform certain shutdown tests, such as inserting neutron flux measuring strips. In order to do this, the Control Rod Drive Mechanisms (the machines that raise and lower the control rods in normal operation) need to be disassembled.

So:
One fine Christmas season, while LS-1 was shutdown for the holidays, and only a skeleton crew was on hand, an evolution to insert neutron flux measuring strips was conducted, by a staff of three (you don’t monkey the reactor vessel on the back shift, and certainly not with a skeleton crew!) techs with limited training. It was determined that one of the control rods was manually pulled almost completely out of the core, leading to prompt-criticality, a massive power excursion, a lethal sleet of neutrons, and one big-ass steam explosion. The reactor vessel was wrecked. Two of the technicans never made it out of the reactor building. The tech who was actually pulling the rod was found impaled to the ceiling when the control rod he on which he was working transfixed him through the pelvis. The one tech who did manage to escape was suffering life-threatening burns, life-threatening explosive trauma, and fatal radiation exposure. He lived long enough to be placed in an ambulance, but died shortly after being “rescued”. IIRC, the Army had to bury the ambulance because it was too crapped-up to be economically decontaminated.

LS-1 was demolished and buried at the National Reactor Facility near Idaho Falls. The Army got out of the reactor business.

3

Tranqulis has most of the facts right. One minor nit to pick: The name of the reactor was SL-1 not LS-1. Here are several links with more details:

http://www.atomicinsights.com/jul96/SL1fact.html
http://darwin.dsm.fordham.edu/ejs/chem/SL1.shtml

As this page says, there is also a movie about the accident:
http://www-cds.aas.duke.edu/filmfestival/program01.html#sl1

4

One more website is: Proving the Principle the history of the INEEL.

There were (are) all sorts of rumors floating around about a possible suicide/murder motive for worker who pulled the control rod. But the simple fact is that we will probably never know for sure exactly what happened and why.

5

Of the first three sites listed by Minkman I would consider only the first to be of any useful value. The second site didn’t connect to anything and the third has problems all its own.

The third listed page
http://darwin.dsm.fordham.edu/ejs/chem/SL1.shtml
is purportedly by Prof. Eric J. Simon but it, at best, reads as a draft in progress. As such there are several missing pieces of data and several errors.

Most glaringly in the website the accident was referred to as a “meltdown” a term that is usually incorrectly tagged to any nuclear accident. In reality a meltdown is when a reactor core goes supercritical and melts its way through the containment structure and into the water table (the term “China Syndrome” parallels this in that the core would melt its way through to China). As mentioned by ** Tranquilis** there was a prompt-critical power excursion which led to a steam explosion. The loss of the cooling liquid removed the moderating water from the reactor which took it back to a sub critical condition.

Also small notes to self are found throughout the document:
195X.
powered by Xkg(?)
(Compare to Hiroshima bomb?)
generated XKw of electricity,
(is this unusually cold?)
(check this!)

The document as listed is, in my opinion, in no condition to be released as “fact” on the internet (of course treating anything on the internet as fact is a high-risk proposition). In short, read the article but take it with a grain of salt.

6

MinkMan, I think I know you. Were you an EO?

7

crc:

Sorry, the typo bug bit the second url. Here it is again.

I agree that the third page is somewhat lacking in detail and appears to be incomplete. I think the professor is is using “meltdown” in the more common, less accurate sense, meaning any uncontrolled criticallity resulting in destruction of the core. I didn’t mean to imply (nor do I think the article implied) that Tranq’s explanation was less than correct.

Tranquilis:

Yes, I was an EO.