Not all used nuclear fuel material is suitable for bombs, particularly the materials found in spent reactor fuel that has undergone a full cycle of use in a reactor. A variety of plutonium and uranium isotopes, the usual materials used to form the core of a nuclear warhead, are found in spent nuclear fuel. The issue is that they are quite difficult to separate from the rest of the material. It possible to do, but not easy. Making a bomb out of used fuel is not a simple process. Current techniques require sizable infrastructure for refining the fuel and extracting the plutonium. This is the sort of industry that the United Nations Security Council keeps a close eye on in the world today. There are very few nations with the scientific and industrial base necessary to build this sort of industry who do not already have nuclear weapons or have chosen to not create them.This is a point often missed by people who lobby against using nuclear power or nuclear fuel reprocessing. They do not realize that a large part of the developed world has both the technical affluence and the available physical resources to create nuclear weapons and yet have chosen not to. The 'nuclear club', those nations who possess nuclear weapons is only composed of The United States, Russia, The United Kingdom, France, China, India, Pakistan, North Korea and probably Israel. There are many wealthy nations that possess nuclear power plants who do not have nuclear weapons such as Canada, Germany, Japan, Finland, South Korea and many others. For the full list see Wikipedia's article on Nuclear Power By Country. These countries have chosen to use their technical ability to create prosperity rather than weapons. This is important because these countries demonstrate that it is by no means a certainty that development of nuclear power technologies leads to availability of weapons.
This is true if the status quo regarding reprocessing continues. With our current system of once-through fuel use for most nuclear reactors, the volume of used nuclear fuel will certainly increase. With increased volume of fuel comes increased difficulty in transport, safety, accounting, and security. As more fuel is used and goes into various kinds of storage, the possibility that a mistake will be made somewhere does go up. In short, it makes thefts of used nuclear fuel more likely.
Someone can steal the fuel
So in the case that someone steals used fuel, they will still need to acquire access to refining equipment if they wish to make a nuclear weapon. In order to get the used fuel to their equipment they would need to transport, most likely over quite a large distance, incredibly dangerous material. Nuclear fuel has many 'features' that make it extremely hard to steal. For starters, the developed world keeps a very close eye on it. The regulations regarding the safekeeping and transport of nuclear waste are quite stringent, and rightfully so. The developed world does not like the possibility of widespread nuclear armaments. Used fuel is a military asset and is usually very closely watched by the militaries of the developed world.
Secondly, used nuclear fuel is highly radioactive. There are a variety of containers employed for the storage and transport of nuclear fuel, all designed to be safe as well as conspicuous. It would not be easy to hide and smuggle a used nuclear fuel bundle in its normal container. If someone changes the container, they risk exposing themselves to large amounts of radiation and toxicity. Assuming that someone can steal the fuel without alerting the military and move it into a container of their own that can correctly shield them from the radiation, they would have a better chance of smuggling the fuel elsewhere.
Lastly, radiation is something we can detect. If fuel went missing, it is possible that instrumentation used by the military would be able to detect nuclear fuel unless it is inside extremely good shielding. It is important to keep in mind that there are several different kinds of radiation being emitted by used fuel. Shielding all of them enough that they are undetectable nearby would require an impressive container. Such a container is technically possible, however.
It is possible to create weapons-grade plutonium without creating electricity for a power grid first. This is accomplished using systems similar to those used during the Manhattan Project. These systems basically consisted of a large amounts of uranium close to each other with a moderating material in between. Fissions would take places as well as neutron-capture events that turn uranium-238 into plutonium-239, a popular weapon material. If a country has access to uranium ore and the industry mentioned above, they can eventually build a crude nuclear weapon. We say crude because this technology took extremely wealthy nations a long time to perfect, and early bombs were nowhere near as powerful as more modern ones, even without considering the fact that we now use hydrogen bombs which are an additional order of magnitude more difficult to produce.
Protecting used fuel in the developed nations still makes tremendous sense, but it seems crucial that we also pay close attention to the development of industry that can separate out weapons materials such as plutonium-239. These are some of the actions that are being taken already by the United Nations to suppress the chances of weapons proliferation in the world today. The political will of the UN Security Council seems to be steady on this issue. They do not want weapons proliferation for several reasons. First of all, nuclear weapons terrify most of the people in the developed world. It would be political suicide in the developed world to advocate policies that clearly lead to weapons proliferation. Secondly, nuclear weapons are part of the reason why the UN Security Council has the members that it does. The superior military power of the members of the nuclear club is not something they would like to see taken away from them. At the very least this is an area in which they do not want a level playing field where many states have nuclear weapons.
Thanks to this joint program between the United States and Russia, hundreds of tons of highly enriched uranium has been down-blended and used in United States nuclear reactors as fuel. This program has turned a huge amount of weapons-grade material into both useful energy and resulting material that is no longer easily used for weapons.
Programs such as these are a crucial part of the nuclear disarmament of the world. Since much of the world uses uranium as an electricity source, it is guaranteed that the market price remains relatively high. A high market price encourages the dismantling of nuclear weapons and the safekeeping of the uranium stockpiles not just because they are dangerous but because they are incredibly valuable. It has been noted that without this program it is likely that the Russian stockpiles would not have been as well-cared-for in the time following the downfall of the Soviet Union.
New reactor designs exist in various stages of development that make significant progress towards closing the nuclear fuel cycle. What this means is that there would be less nuclear waste from a system such as this. In theory it may be possible to someday design and engineer a system that will produce only very, very small amounts of waste.
These designs exist primarily on paper, but some of them have been prototyped in the past. We have good reasons to believe that many of them have significant merit, but scale prototypes are necessary to refine their construction and operation. We can currently make estimates on cost, but there are generally a large number of unknown or uncertain variables that will affect the cost of these theoretical reactors.
A lot of research is still required to be confident that these reactors can actually deliver as expected. The possibilities for future development are compelling because it seems possible to design reactors that are more safe, reliable and inexpensive along with reduced proliferation risk. Some of these designs have systems wherein the fuel never leaves the reactor site for reprocessing. The reprocessing system is designed into the power plant so that there should not be a need to move large quantities of used fuel around for reprocessing and then redistribution. Each of these reprocessing systems would have to be very inexpensive in order to include one economically with each power plant. This is noteworthy because reprocessing facilities for today's fuel cycle cost several billion dollars.
Reprocessing techniques usually involve chemically working with the fuel between intervals where it is in the reactor. There are a number of approaches which will not be elaborated upon here. Suffice to say that there seem to be some practical proposals for safe and affordable nuclear power sources that will help reduce the threat of proliferation. This is claimed because they have some or all of the following properties:
- they can burn up some of our current stockpiles of nuclear waste.
- they can be used to burn up weapons-grade materials, reducing the volume of nuclear stockpiles.
- the fuel cycles are designed so that the fuel is never in a state in which it is easy to steal and separate out plutonium or any other material useful for building nuclear weapons.
On the other hand, an equally valid argument is that the forward march of science has brought with it increased health, safety, and enjoyment for much of the world. The same chemistry that unlocked the dangers of guns and bombs made possible almost every facet of the modern era. Everything from the materials that make our homes and cars to the food we eat and the medicines we consume owes part of its intellectual heritage to basic chemistry. With advancing science comes an empowerment of humankind. It is clear that this power can be used by humans to do harm to each other. The question is whether it will be used as such.
This brings us to the second premise, that the net effect of our advancing knowledge in this area will be negative. That is, the additional danger outweighs the possible benefits. Humans will use this advanced technology more for evil than for good. This premise assumes that regardless of the good or evil nature of those people who develop additional energy technologies, their discoveries will lead to horror and pain for humankind.
For the purposes of discussion, the worst-case scenario is one in which the people developing the technology are the ones who will use it. That is, the most advanced nuclear nations in the world-the USA, France, the UK, Russia and China-will choose to use their powers for evil. In this case, they already have the power to do so. Fearing them is moot in this discussion.
A more reasonable scenario is that the technology or the materials involved will be stolen by someone else, and used for evil. For this discussion, see the above section on about how someone can steal the fuel. The scientific discoveries have shown that these weapons that we all fear so much are thankfully relatively hard to build. The fact is that the personal stance on nuclear weapons is rather homogeneous throughout the world. People fear them, and rightfully so. Those nations that consider producing them are quite likely acting somewhat in their own self-defense. Ownership of a nuclear arsenal is pretty much guarantee that no one is going to invade you. Much of the world fears and distrusts the nuclear powers because they quite literally have doomsday machines, and that isn't something most people want to exist at all.
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