After reading the latest straight dope classic, I started researching nuclear power out of curiosity. It started thinking about how nuclear waste lasts for millions of years and then wondered how they stored it. After researching how they store nuclear waste it is clear that there is not a completely figured out solution to storing this waste, but there was a once proposed and now canceled solution of Yucca Mountain and a laser that can destroy the waste, but it is only in developmental stages. Obviously this radioactive waste is stored somewhere right now. Logic would tell me that where ever it is in is holding it or it would have already eaten its way out and we would be researching nuclear holocaust instead of nuclear waste storage. So I guess the question is… What is the nuclear waste stored in currently, and if it can’t be stored, then what is doing right now? Chillin’?
Edited thread title to indicate subject.
Colibri
General Questions Moderator
It’s stored at various places throughout the county. The idea behind Yucca Mountain was that it would be a centralized storage place.
One of those places is Hanford Nuclear reservation. It’s being cleaned up now, but it used to “glow.”
How may I ask is a laser going to destroy the waste?? If you hit the waste with enough power to vapourize it you have an even bigger problem - **gaseous **radioactive waste.
The waste is being stored on-site at the nuclear plants. This is a completely workable temporary solution. And by temporary I mean probably for decades.
Storing small amounts of waste is no big deal. The waste is much less hazardous than the fuel itself, after all. Eventually individual plant storage becomes a problem but only when it outstrips the storage facilities or the plant goes out of business. There are some worries that having hundreds of sites may be less safe for a terrorist to steal the stuff, but that’s an argument about the fuel too. So far there have no attempts, to my knowledge. And nuclear plants are incredibly secure.
Most of your fears about nuclear waste are overblown nonsense, spread by ideologues who hate the concept. There are some very real problems as well but there are very real problems with every source of energy, and I do mean every.
A Scientific American article in the August 2009 issue covers the whole subject well. It makes the case that we can afford to wait until we have a really good solution.
Just to clarify, the only waste stored at power plants is the high level spent fuel. This is what Yucca Mountain was for, to get it all into one isolated (mostly) location. All of the other nuclear wastes are shipped away from the power plants.
For the people that don’t remember Wisconsin and it’s red granite was one of the sites they seriously considered to store the country’s nuclear waste. I don’t remember besides Wisconsin and Yuca Mountain, where else the central storage was proposed. There were only a few states that had to fight to keep the depository from being there. Anybody up for radioactive cheese?
It’s worth noting that one of the problems with nuclear waste is that you want to keep it separated a bit – packing it too closely together can, and has, resulted in critical mass being achieved, and resulted in criticality accidents. Not to exaggerate the risk…any reasonably large facility should be able to store a lot of it. But there are rules for moving the containers around so that you don’t accidentally pass too much of it too near another mass of it, and so on. One does need a bit of room to do this safely. Therefore any national central repository can’t just be a small hole in the ground.
Why would they have to move it? Well, one reason is to change the containers periodically. Radiolysis is the term for how radiation changes matter, breaking up molecules and even changing atomic structure over time. A typical 3013 container can be broken down over time by its own radioactive contents, and some of the atoms of the stainless steel (iirc, iron and carbon mostly) would be changed to other elements. Eventually you’d have 99% stainless steel and 1% various other crud, gradually weakening the container. For that reason among others (gas buildup as radiolysis separates hydrogen from water condensation being one), the containers are regularly inspected and occasionally opened and their contents put into brand-new containers.
Can we get a cite for spent fuel achieving criticality when stored together too closely? I know that can happen with fresh fuel (after all, that is what a reactor is), but I was under the impression that spent fuel had trouble maintaining criticality.
I don’t know exactly what the OP was referring to, but you can destroy nuclear waste by bombarding it with neutrons from, for example, a Farnsworth Fusor. The containment vessel will itself become radioactive of course, but I believe that the waste is lower level that the spent fuel.
How do the relatively much more nuclear-friendly French deal with their nuclear waste?
While I would agree that on-site above-ground storage is a workable solution for an indefinite term, the fact remains that many of the facilities built for the storage of waste were intended only to be used for a few years, not decades, and do not have corrosion resistance provisions and maintenance plans and schedules intended for long-term storage, and the current storage plans for spent fuel, radioactive coolant, and the highly reactive byproducts of the nuclear fuel processing and refinement cycle are often ad hoc. This is especially true in the former Soviet Union where the facilities themselves are often poorly maintained, but also the case in the United States and Britain. The total cost of the nuclear production lifecycle (including progressively more demanding regulatory costs) was not historically rendered accurately.
I’m not clear about the claim that “the waste is much less hazardous than the fuel itself,”; the fuel is chemically stable and typically sealed in tubes, blocks, or pebbles. Of course, putting enough of the fuel together in one place with the appropriate moderator can result in criticality, but the sort of prompt criticality required for a dramatic explosion just isn’t possible with most fuel-grade uranium, nor would it be possible for a terrorist group or other organization that did not have a significant amount of technical prowess and access to very sophisticated equipment, labor, and energy to process fuel-grade enriched uranium into the highly enriched uranium suitable as weapons material. Similarly, while plutonium is easier to separate, producing the right kind of plutonium ([sup]239[/sup]Pu) for weapon-grade use requires sophisticated processing and handling equipment as well as access to a functioning reactor or neutron source. Quite simply, outside of television shows staring Kiefer Sutherland as an indestructible superhero in the guise of a simple government agent, terrorist groups are not going to be converting fuel or waste into a nuclear fission bomb.
On the other hand, the uranium hexafluoride (one of the chemicals that comes from the processing of uranium ore and enrichment) is violently reactive and toxic, in addition to being radioactive. It would be nasty stuff to release into a city center or a metropolitan water supply.
Criticality accidents aren’t typically a problem with radioactive waste or spent fuel, although they can be an issue with “live” fuel and especially during the processing and enrichment stage. This is dealt with by very simply not having enough material in one place at one time except in the actual reactor. Criticality excursions due to the reactor entering a dangerous regime can be a problem, but they can also be designed out by the use of a self-moderating or self-limiting system.
France has an extensive fuel reprocessing program and also is one of the few nations that has invested significantly into breeder reactors (reactors in which the fuel is converted into more fuel as it fissions). While this may sound like a solution to waste problems, it is also not currently fiscally advantageous and produces a lot of additional high level waste to be disposed of, and existing breeder reactors are all fast fission designs that are not inherently fail-safe. France currently stores waste in above-ground containers while still trying to develop a site and technologies for long-term underground storage.
The problem with dealing with nuclear waste isn’t that there aren’t suitable means and methods to process and store waste, but that escape into the environment has the potential for a persistent, high criticality threat to health and well-being of the general public. A single human failure or engineering miscalculation could potentially pose a hazard to thousands of people, and so there is quite reasonably a great deal of concern both politically and practically as to the threat posed by accidental leakage or deliberate dispersion of nuclear waste material.
It does not help that the current regulatory environment is resistant to innovation and adoption of proven but not commercialized means of processing and reduction, such as the use of subcritical hybrid reactors, so even though safer methods and technologies are conceptually possible, they’re not practically available. The current state of the nuclear power industry in the United States is essentially the same as it was at the time of the Three Mile Island excursion; in other words, we’re thirty years behind where we could be, and many reactors and waste handling systems are both beyond capacity and have outlasted the design lifetime. The same (if not moreso) is true for reactors in Russia, the Ukraine, and other former East Bloc nations.
It is certainly possible, at least on paper, to build and operate facilities that would not only reduce the amount of waste produced from the reactors themselves but also the fuel production cycle by going to systems that are not a once-through cycle or cultivate additional fuel with minimal reprocessing. But there are no real plans for implementing these technologies in the near term.
Stranger
A real big storage site is about 9 miles from my house
Shearon Harris Nuclear Power Plant - Wikipedia
From some areas 10 miles away I can see the water coming out of the cooling tower
When the fuel is first removed from the core it is stored in the spent fuel pool for about 5 years. There is so much decay heat from the spent fuel it needs active cooling to remove the heat. After, 5 years the decay heat has decreased enough to allow storage in a container that has passive cooling. The spent fuel is put in very large sealed concrete and steel containers that are kept on site.
You’ve probably been reading the anti-nuclear side of the story and so you are not actually getting accurate information. You’ll hear that there is 100,000 tons of high level waste. The antis use this number to make the amount sound very large. How are we going to store it all? Since the spent fuel is very dense the volume of the waste is not very large. All the spent fuel in the country could be stored in a building the size of a football stadium.
You said that the waste is dangerous for millions of years. This is not entirely accurate. The antis say this to make it sound like an insurmountable problem. Yucca mountain needs to be designed to store waste for 10000 years. A long time but not insurmountable. Radioactive waste is a self correcting problem. Time solves the problem.
IMO, this is what will happen. Spent fuel will eventually become worth enough that we’ll start reprocessing it. After its decayed for 50 years or so it will be easier to work with since the radioactivity will have decayed significantly. Therefore reprocessing it will be a lot safer. Again, IMO Yucca mountain isn’t even needed. We’ll never store the waste for 10,000 years. Yucca mountain is mostly a boondoggle made up by the antis to inflate the costs of nuclear power to make it unprofitable.
Breakfast is ready, maybe more later.
When Stranger wrote: “Terrorist groups are not going to be converting fuel or waste into a nuclear fission bomb.”
I could hear a collective sigh of relief over Doper-land.