Indeed, as many as a quarter of commercial nuclear energy facilities in America are cash-flow negative, or may be so soon, or could be facing difficult investment decisions which may lead to early shutdowns. Such a contraction would have a significant impact beyond the commercial nuclear energy sector, affecting university physics and engineering programs, material science laboratories, manufacturers, labor programs for training nuclear welders, and much more.
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Friendship grows stronger in adversity. Only a handful of passes, typically four or five, are needed to boost LEU to weapon-grade levels. Therefore, an LEU enrichment plant is a latent nuclear explosive material factory. However, as long as safeguard inspections are applied to the plant, the operator would have to be concerned that HEU production could be detected.
But if the government that owns the enrichment plant wanted to produce HEU, it could kick out inspectors and abrogate its safeguard agreement. Like uranium, plutonium is a heavy element with certain types of isotopes that are very suitable for nuclear fission. In particular, plutonium is the most suitable fissile isotope. Unlike uranium, which has a radioactive half-life of several hundred million years, plutonium has a relatively short half-life of about 24, years. Half-life measures how long it takes for one half of a sample of a radioactive isotope to decay to a different isotope.
On the geological timescale of billions of years, uranium lasts a long time, and plutonium decays rapidly. Thus, any plutonium that was present when the earth formed about four billion years ago is no longer present. Consequently, to have plutonium available for fueling bombs, manmade processes are needed to produce this isotope.
Nuclear reactors produce plutonium when uranium in the fuel mixture absorbs neutrons. After a uranium nucleus absorbs a neutron, it turns into uranium After two relatively rapid radioactive decays, the uranium becomes plutonium Because a fuel mixture that has been in an operating reactor includes a large amount of highly radioactive fission products, rigorous safety precautions are required to ensure workers are not exposed to harmful radiation from the spent fuel.
A reprocessing plant is designed to safely remove or extract the plutonium from the fuel mixture. Reprocessing involves a series of physical steps and chemical reactions to extract plutonium. The first physical step is to chop up the spent fuel into pieces. These pieces are then sent into a vat of hot nitric acid to remove the fuel cladding from the fuel and fission products. The fuel consists of uranium, uranium, and plutonium in different isotopic forms.
In addition to the fission products, uranium, and plutonium in the fuel, the mixture of materials includes other transuranic heavier than uranium isotopes such as americium and neptunium. Fission products are lighter than uranium and plutonium. After removal of the fuel cladding, the mixture of materials is combined with kerosene and tri-butyl-phosphate TBP to remove uranium and plutonium from the fission products and other radioactive materials. The separated plutonium can then be combined with depleted uranium to make mixed oxide MOX fuel.
The proliferation hazard in PUREX reprocessing is that plutonium is separated from the highly radioactive fission products. These fission products provide a protective lethal barrier against theft of unshielded spent fuel containing plutonium. Because plutonium is not very radioactive, separating plutonium from the fission products leaves it potentially vulnerable to theft.
Thus, separated plutonium should be guarded as if it were a nuclear weapon because it is directly usable in such a weapon. Like uranium, plutonium has different grades that vary in their suitability for weapons. Essentially, the greater the concentration of plutonium, the more suitable is a plutonium mixture for weapons.
Weapons-grade plutonium has less than six percent of its isotopes as non-plutonium Fuel-grade plutonium is defined as having more than six but less than 18 percent of non-plutonium isotopes. Reactor-grade plutonium has greater than 18 percent of these isotopes. Many of the non-plutonium isotopes tend to undergo spontaneous fission relatively often and thus a large concentration of these isotopes can result in a greater likelihood of a nuclear bomb producing a fizzle yield less than design yield because the explosive chain reaction would start prior to full assembly of the fissile material.
Nonetheless, some nuclear explosive yield would likely occur in a nuclear bomb made from reactor-grade plutonium.
While some nuclear industry officials have questioned reactor-grade plutonium's usefulness in nuclear weapons, the U. Department of Energy clearly stated in that this type of plutonium is weapon-usable. There is no prospect of security against atomic warfare in a system of international agreements to outlaw such weapons controlled only by a system which relies on inspection and similar police-like methods…rivalries are inevitable and fears are engendered that place so great a pressure upon a system of international enforcement by police methods that no degree of ingenuity or technical competence could possibly hope to cope with them.
This conclusion came from the Acheson-Lilienthal Report of , issued by the United States government and mainly drafted by J. Robert Oppenheimer, the scientific leader of the Manhattan Project, which produced the first nuclear bombs. This report became the basis of the Baruch Plan, which was placed before the United Nations in and offered a proposal for international control of nuclear energy.
While this proposal was not passed by the UN, it has periodically been resurrected in various incarnations throughout the next sixty plus years. Here, the focus is not to provide a detailed discussion of these various proposals and other options for controlling proliferation risks. Instead, this Issue Brief provides a concise tutorial about the concepts behind these proposals.
The proliferation-control concepts involve political, financial, and technical solutions. With respect to the political dimension, the first issue to be understood is that national governments want to protect their right to control what happens inside their states' territories. They also want to ensure they keep all of their rights assigned to them under international treaties.
In article IV of the NPT, it is declared that a state has the "right" to peaceful nuclear technologies as long as the state maintains safeguards on its peaceful nuclear program and does not manufacture nuclear explosives. While this article does not specifically mention uranium enrichment and plutonium reprocessing technologies as part of a state's right to peaceful nuclear technologies, it does not explicitly exclude enrichment and reprocessing technologies.
Recently, there has been considerable renewed debate about whether this right should be interpreted to include these bomb-usable technologies. Thus, non-nuclear-weapon states such as Argentina, Brazil, and Japan, for example, have pursued enrichment or reprocessing or both and have maintained safeguards on these programs. Iran claims that it wants to be like Japan and have a peaceful nuclear program that includes enrichment and possibly reprocessing.
While Iran does not at this time appear willing to give up its uranium enrichment program, the dilemma this program poses to international security has renewed interest in political and financial incentives that would try to dissuade countries from engaging in enrichment and reprocessing. One option is to offer fuel services contracts that are very economically competitive. Under this scheme, a country or group of countries would guarantee that a state in need of nuclear fuel would always have that fuel provided as long as that state did not enrich uranium or reprocess plutonium.
The fuel services could also include spent fuel management in which the service providers would agree to remove the spent fuel and safely and securely store it. Such action would remove the material the state would need to extract plutonium for a weapons program.
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