Permanent disposal

Spent nuclear fuel has fission products, uranium, and transuranic elements. Plans call for permanent disposal in underground repositories. Geological studies are in progress at the Yucca Mountain site in Nevada. Until a repository is completed, spent fuel must be stored in water pools or in dry storage casks at nuclear plant sites. 

Zirconium phosphate [13772-29-7] also absorbs cesium and other radioactive-decay daughter products, and has been proposed as part of permanent disposal systems for nuclear fuel waste processing. 

Twenty Year Retrievable Interim sites will become permanent disposal sites. Or... 

The waste material will be exhumed and reprocessed. New waste criteria will be applied to the subsequent residues which will be compatible with the permanent disposal sites. 

At present, no country in the world has yet implemented a system for permanently disposing of the spent fuel (Deutch and Moniz, 2006). Since 1979, a salt dome in Gorleben (northern Germany) has been under investigation for final storage of nuclear waste. In 2000, a moratorium stopped the work for a period of three to ten years. To date, around 1.3 billion have been invested in the Gorleben project. 

Deep geological disposal is the most favored solution for the permanent disposal of nuclear wastes with long half-lives. Although the locations of the burial places are selected with outmost care to avoid migration of the wastes in nature over a very long period of time, no barrier can be safe forever, so, numerous studies are in progress to determine the main factors that could cause leaks of radioactive nuclides. Soluble compounds in ground water are likely to play a major role in the release of actinides. 

For any on-slte disposal system, there are at least four criteria that should be met to decrease the chance of environmental contamination and either eliminate or decrease the need for disposal at a permanent facility. First, the disposal system would need to concentrate the large volume of waste to Increase ease of handling and permanent disposal. Secondly, the disposal system would be required to contain the pesticide wastes to avoid environmental contamination or risks to human health. Thirdly, the system should prevent toxic levels from vaporizing Into the air. Finally, the disposal system should degrade and detoxify the pesticide wastes In the containment, particularly If buildup of the wastes to toxic levels Is a potential problem. 

In parallel Canada also pioneered work on the immobilization of radioactive wastes into glass (vitrification) for permanent disposal. (O A natural mineral, nepheline syenite, was used as the basic material because it produced a glass with excellent... 

According to Robert T. Mueller of the State of New Jersey Department of Environmental Protection (NJDEP), demonstrations conducted by the vendor have supported the premise that the cost to vitrify waste into nonleachable materials is substantially lower than the excavation and relocation of these materials to regulated landfills as a means of permanent disposal (D17164M,... 

Without going into great detail about the issues described in these papers, I would like to make the point that the response of the waste isolation program to these papers will be to use them to help us to design a technical program plan to ensure that these issues are adequately addressed, as indeed they must be, before we can commit radioactive waste to irretrievable permanent disposal. 

Nevada Test Site, hopefully as early as 1979. Both of these experiments are strictly to establish a better understanding of the interactions between thfe waste form and the media. In neither case is the experimental location considered as a permanent disposal location. 

Fig. 3ft. Some authorities prefer rock sail deposils for ihe permanent disposal of nuclear wasles on ihe assumpiion ihai lhe heal generaied by radioaclive decay would fuse salt and wastes into an impermeable mass. Other experts question the integrity of salt formations. Increasing attention has turned to hard media, such as the granitic and basaltic rocks, and to shale and clay formation, with the hope that the extensive occurrence of such formations would minimize the need to transport wastes over long distances...

Because a permanent disposal strategy has proven illusive due to technical and political considerations, plans have been made for interim storage facilities where... 

As discussed in Chapter 3, at least trace amounts of arsenic commonly occur in rocks, soils, sediments, sludges and spent sorbents from water treatment systems, coal ashes, industrial wastes, and many other natural and artificial solids. Depending upon whether they are considered regulatory hazards (Appendix E), solid materials may require treatment before disposal (waste management) or remediation if they are located at a contaminated site. For solids, arsenic treatment may involve reducing the arsenic concentrations in the materials so that they are no longer hazardous (for example, soil washing). However, because arsenic cannot be destroyed, eventually the element will require permanent disposal in a manner that does not... 

NCRFs recommendations on classification of hazardous wastes are based on two principles. First, a classification system should be generally applicable to any waste that contains radionuclides, hazardous chemicals, or mixtures of the two (i.e., the system should be comprehensive). Second, waste that contains hazardous substances should be classified based on considerations of health risks to the public that arise from waste disposal, because permanent disposal is the intended disposition of materials having no further use. 

High-level waste thus includes the concentrated wastes that arise from reprocessing of commercial or defense nuclear fuel that contain virtually all the fission products and transuranium radionuclides (except plutonium) in spent fuel. However, the definition does not mention the constituents of the waste, and it is only qualitative because concentrated is not quantified and the minimum fuel burnup that would yield high-level waste is not specified. Although the definition given above referred only to liquid (aqueous) waste, it is clear from further discussions in 10 CFR Part 50, Appendix F (AEC, 1970), that AEC intended that high-level waste also would include concentrated solid waste derived from liquid high-level waste that was suitable for permanent disposal. 

Requirements for Disposal. The first requirements for disposal of commercial high-level waste were developed by AEC in 10 CFR Part 50, Appendix F (AEC, 1970). AEC specified that liquid high-level waste shall be converted to dry solids and transferred to a federal repository, to be designated later, for permanent disposal. 

Requirements for Disposal. The National Security and Military Applications of Nuclear Energy Authorization Act (NSMA, 1980) established the current DOE program for disposal of defense transuranic waste at the WIPP facility in New Mexico. The Act specifically authorized test emplacements of waste for purposes of research and development. WIPPLWA (1992) then authorized permanent disposal of defense transuranic waste at this facility. The Act specifies that the WIPP facility may not be used for disposal of high-level waste, commercial transuranic waste, or any DOE non-defense transuranic... 

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