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Spent nuclear fuel stays a radiation hazard for extended periods of time with half-lifes as high as 24,000 years. For example 10 years after removal from a reactor, the surface dose rate for a typical spent fuel assembly still exceeds 10,000 rem/hour—far greater than the fatal whole-body dose for humans of about 500 rem received all at once.
The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. It consists of steps in the front end , which are the preparation of the fuel, steps in the service period in which the fuel is used during reactor operation, and steps in the back end , which are necessary to safely ...
The radiation hazard from spent nuclear fuel declines as its radioactive components decay, but remains high for many years. For example 10 years after removal from a reactor, the surface dose rate for a typical spent fuel assembly still exceeds 10,000 rem/hour, resulting in a fatal dose in just minutes. [20]
Spent nuclear fuel contains abundant fertile uranium and traces of fissile materials. [20] Methods such as the PUREX process can be used to remove useful actinides for the production of active nuclear fuel. Another option is to find applications for the isotopes in nuclear waste so as to re-use them. [115]
The Nuclear Waste Policy Act of 1982 established a timetable and procedure for constructing a permanent, underground repository for high-level radioactive waste by the mid-1990s, and provided for some temporary storage of waste, including spent fuel from 104 civilian nuclear reactors that produce about 19.4% of electricity there. [38]
High-level waste is the highly radioactive waste material resulting from the reprocessing of spent nuclear fuel, including liquid waste produced directly in reprocessing and any solid material derived from such liquid waste that contains fission products in sufficient concentrations; and other highly radioactive material that is determined, consistent with existing law, to require permanent ...
The first large-scale nuclear reactors were built during World War II.These reactors were designed for the production of plutonium for use in nuclear weapons.The only reprocessing required, therefore, was the extraction of the plutonium (free of fission-product contamination) from the spent natural uranium fuel.
The high short-term radioactivity of spent nuclear fuel is primarily from fission products with short half-life.The radioactivity in the fission product mixture is mostly due to short-lived isotopes such as 131 I and 140 Ba, after about four months 141 Ce, 95 Zr/ 95 Nb and 89 Sr constitute the largest contributors, while after about two or three years the largest share is taken by 144 Ce/ 144 ...