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Nuclear Info Kept From Congress and the Public
Thermite writes "On March 6, 2006 an accident occurred at Nuclear Fuel Services in Erwin, Tennessee. According to reports, almost 9 gallons of highly enriched uranium in solution spilled and nearly went into a chain reaction. Before the accident in 2004, the NRC and The Office of Naval Reactors had changed the terms of the company's license so that any correspondence with Nuclear Fuel Services would be marked 'official use only.' From the article: 'While reviewing the commission's public Web page in 2004, the Department of Energy's Office of Naval Reactors found what it considered protected information about Nuclear Fuel Service's work for the Navy. The commission responded by sealing every document related to Nuclear Fuel Services and BWX Technologies in Lynchburg, Va., the only two companies licensed by the agency to manufacture, possess and store highly enriched uranium.' The result was that the public and Congress were both left in the dark for 13 months regarding this accident and other issues at the facility."
Congress was not kept from the results. The public was. Anything marked "For Official Use Only" (with or without the "for") is self-regulated. Meaning, if you aren't doing it for official use, you stop yourself from reading it. It also means you can't distribute it willy-nilly.
All members of Congress have at least the right to view FOUO information. Some politicians disagree with marking this material as such, and they are quoted in the article. But at NO TIME were they banned from the information.
The title written as it is lends itself to a much more insidious plot, and that is far from what occurred.
Any container designed to hold enriched uranium would be carefully shaped so as to avoid coming anywhere near to creating a critical mass. In this incident, the risk was that the liquid would flow into the elevator shaft, where it would pool into a compact shape that could create a critical mass.
It wouldn't have caused an explosion, just a chain reaction a la what is sustained in a nuclear reactor - except this would be completely uncontrolled and unshielded. As everyone here probably knows, fission is caused by one neutron busting apart a big nucleus, throwing out more neutrons (among other things). Criticality happens when there are more neutrons in a given "generation" (instant, essentially) than the previous generation (for a given geometry, etc). In a power reactor this ratio of neutrons in a given instant to the previous instant (k) is (very close to) 1 - ie the neutron flux remains (relatively) stable across short time frames (the flux varies significantly with fuel burnup). Once you go to k > 1, the reaction increases very rapidly and thats when things get dangerous in an uncontrolled environment. There would be "nuclear reactions", even fission, going on in a tablespoon of the stuff, just not at a rate necessary to create a chain reaction and establish criticality. How much of this stuff it would take to create and maintain a chain reaction depends on a lot of things - geometry, what else is in the liquid solution (ie anything hydrogenous would help thermalize/"slow-down" the neutrons to the point where fission is most likely, maintaining the chain reaction), and the amount of enrichment (since this is weapons/navy grade stuff, it was extremely high, meaning you wouldn't need much). That said, I don't have a good estimate of how much of this stuff it would take, but I do know that a sphere of pure Pu-239 a little bigger than a softball (~12kg) is a critical configuration. I have a BS in Nuke Engineering, but haven't had a reactor theory course for a few years and shifted career paths, so I apologize for any errors.
Keep in mind that this event's worst case result from this would have been:
e gs/staff/sr0090/v29/sr0090v29.pdf
"If a criticality accident had occurred in the filter glovebox or the elevator pit, it is
likely that at least one worker would have received an exposure high enough to cause acute
health effects or death." Keep in mind that the result of the second worst event for nuclear facilities for the year. Compare that with the coal industry or oil industry where there are multiple deaths annually.
Also this is fairly old news since it was in the NRC's "Report to Congress on Abnormal Occurrences - Fiscal Year 2006 (NUREG-0090, Vol. 29)". Which has a release date of April 2007. Take a look for yourself its on page 14
http://www.nrc.gov/reading-rm/doc-collections/nur
The information is available to congress is not notified everytime an incident occurs. Unless the accident could cause things to happen off site the public isn't notified until the annual list of inccidents, primarily because it would just create unneeded hystaria as seen by this FUD while the engineers review the facts and figure out REALLY happened. As far as the company trying to hide it. If it is not reported to the NRC within 24 hours of the event they would likely lose their license.
(It is also worth noting that the Lib Dems control a very large number of local authorities. Pissing them off can therefore have interesting consequences. It would be most unfortunate if a new sewer had to be installed in the road... right outside an MP's house... Terrible... Don't know how that could have happened...)
Both the opposition and the third party have other weapons that do not exist in America. Either can call for a motion of no confidence, in which the Prime Minister MUST appear to answer questions. As indeed they must for Parliamentary Question Time. Although it has not been used this way for years, it used to be standard practice to use no confidence motions to force the other party to turn up for important debates, as the Prime Minister must resign if the motion passes. It is vital to that party that it can guarantee as large a majority as possible. Question Time is also important, as it creates a much greater sense of accountability. It's not perfect, but it gets better answers than subpoenas seem to be in America.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Oh Please for sure.
We are supposed to believe that 9 gallons of enriched Uranium won't go into chain reaction but if you spill it onto a floor where it spreads out the chances of a chain reaction increases?
when Pigs fly.
Check out the Barns radius.
Running with Linux for over 20 years!
The containers are usually barrels. The important consideration here is the total mass of the material stored. US facilities usually store the Uranium/Plutonium/Thorium/etc as disolved salts. The whole suspension is then labeled as radioactive waste, but the total mass of the material is fairly low. If the concentration gets too high, considerable heat can be generated. That has happened at some US plants in the past. The solution is to limit the volume stored in any one container. If you don't plan to ever use it for anything, a little boron helps too. To get a chain reaction, you need to moderate the reaction somehow. The neutrons have specific energy bands (read temperatures) where they are absorbed by the tartet neuclei When emitted, they have too high an energy. (Un)Fortunatly, the hydrogen in the water is a moderator, so it CAN work. The next requriement is to concentrate the solution, to increase the mass of the reactant. You need something that is the exact opposit of the puddle on the floor. That spreads (thins) the reactant out, reducing any ability to sustain a chain reaction. A mop bucket would work better. A lot of the posts above were positing a 'blue flash' you won't see one of those unless you are getting close to a bomb type of reaction. If you do see one, you are already dead. The blue is secondary radiation. To get enough to see in a lit room, you have to be way over the amount of hard radiation that would kill you. You probably have around enough time to arrange your funeral. Say a couple of days. Don't count on being able to do anything on the last day, though.
Everybody knows 3 people with my name.
We are supposed to believe that 9 gallons of enriched Uranium won't go into chain reaction but if you spill it onto a floor where it spreads out the chances of a chain reaction increases?
No, we're supposed to believe that an improperly sealed transfer line could allow sufficent uranium to accumulate in two possible places over the course of multiple transfer operations.
Report PDF
-- 3 events that reshaped the world in the 20th century: WW1, WW2, and WWW
Chernobyl had a lot more mass of fuel, already hot, contained in a pressurized vessel. When the reaction got out of hand, it superheated the water causing a steam explosion that blew the top off the vessel, spewing part of the reactor contents into the air and also causing a graphite fire that released even more radioactive material. Since the fuel was in solid form, the bulk of it was not easily mobile, allowing it to stay at a critical mass and density while it heated to a lava-like state and melted it's way downward into the ground while keeping the graphite fire burning.
This incident involved 9 gallons uranium and an unspecified solvent at an unspecified concentration and occurred at a processing plant, not a reactor. Had a critical mass pooled, it would have started heating up as the reaction rate increased. This would have caused the solvent to boil, mobilizing some of the radioactive particles but keeping the pool somewhat dispersed, in turn reducing the reaction rate...a sort of natural moderation effect. Actually, this is pretty much the main challenge to overcome in detonating a fission bomb. They like to sputter themselves apart before you get an effective yield.
Because of the self-moderating effect and the lack of any way to build up pressure, there could be no explosion from this spill. It might start a fire, however, which could be expected to increase the amount that becomes airborne, and of course cause additional hazards if the fire spread. A fire can be fought, by the way, although you want to take extra care not to spread the uranium to places where it's harder to clean up.
The increased radiation and perhaps irradiation from the reaction would be a hazard to anyone working in the immediate area. The NRC said there was a possibility of one worker receiving a fatal dose of radiation had it gone critical. The actual uranium that might become airborne is a surprisingly minor hazard. In fact, the wikipedia article has a picture of someone holding U-235 pellets in their hand. It is highly toxic and this is the main threat, but you still need to get a sufficient dose to cause problems. Its radioactivity is actually very low when not in a chain reaction, with a half life of 700 million years. The bigger concern is the daughter isotopes created by its decay with shorter half lives, like radon, but these of course only form at the rate the uranium decays, so it's typically only a problem with very large deposits.
Also, if you read the article in full, you will see that the Nuclear Regulatory Commission already did an investigation (part of what was classified) and gave the company a list of required operational changes to help prevent this sort of thing from happening in the future and mitigate damage if it does.