Disposition of High-Level Waste and Spent Nuclear Fuel The Continuing Societal and Technical Challenges (2001) / Chapter Skim
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7. Alternatives to Geological Disposition
7. Alternatives to Geological Disposition
Pages 114-126
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From page 114... ...
while at the same time developing an option for geological disposal so that an ongoing commitment to active management can, at some future time, be brought to an end. Geological disposition and surface storage (see Sidebar 1.3)
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From page 115... ...
From a technical point of view, there has been no urgent need for final disposal facilities because of the recognized high level of safety of interim storage facilities, the relatively small volumes of long-lived radioactive waste from civilian programs, and the storage time needed to allow adequate cooling of the more radioactive waste before geological disposal can take place.
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From page 116... ...
review included the following regarding extended surface storage: In virtually all countries, some period of interim surface storage to allow decay of radiation and heat generation has always been recognized to be necessary or valuable. This interim storage is often at a centralized location, but can also be at individual facilities....
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From page 117... ...
For the geological disposal option, long-term safety is provided by the geological characteristics of the site and the protection afforded by engineered barriers that are part of the repository design. The main features, events, and processes (reps, see Sidebar 6.3)
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From page 118... ...
Surface storage involves uncertainties in whether future generations will continue to provide the resources to assure safety and security. Performance of a geological repository involves uncertainties in the geological setting and in the changes that may occur over time in engineered barriers, as well as the possibility of deliberate or inadvertent human intrusion.
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From page 119... ...
Partitioning and Transmutation An approach that has been claimed to have the potential to change the future of geological disposal is partitioning and transmutation (P&T) of long-lived radionuclides to give wastes which have shorter half-lives and therefore do not present as serious a challenge to the isolation capacity of repositories.
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From page 120... ...
To achieve these very high separation factors, much more advanced and sophisticated reprocessing technologies than those available today are required. The reasons offered to support P&T are to make geological disposal safer and easier by reducing the volume of HLW, especially the long-lived radioactive constituents; to address plutonium management; and to extract valuable materials.
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From page 121... ...
E-1, 2~. "The inventory of fissionable materials from commercial spent fuel in the repository could be reduced by a factor of 1,000....
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From page 122... ...
Geological Alternatives to Mined Repositories: Subseabed and Deep-Borehole Options Approaches for isolating radioactive waste on earth by means other than geological disposition in mined, engineered repositories are discussed briefly in this section. These are variations on the basic concept of
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From page 123... ...
Emplacement in deep boreholes drilled from the surface is an approach to geological disposition that avoids the mined repository. Disposal in shallow boreholes was a normal practice at the "Radon" low-level waste disposal sites of the former Soviet Union, and it is still practiced in many former Soviet countries (IAEA, 1995a)
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From page 124... ...
Direct injection of liquid waste or slurries of liquid waste and grouts is essentially a form of geological disposal that uses neither a waste package (e.g., a metal waste container) nor a mined repository.
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From page 125... ...
However, based on what is known today, several important conclusions can be drawn: · There does not appear to be any promising alternative to geolog~cal disposal for permanent isolation of HLW that avoids a need for ongoing active management. · The only two alternatives capable of assuring safety and security on the time scale of decades to a few centuries are geological disposition and continued surface storage.
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From page 126... ...
Underground emplacement of HLW with retrievability is an alternative to surface storage, and neither surface storage nor such geological disposition precludes shifting to another disposition approach later. The major choice for nuclear programs for coming decades is how to assure the safe and secure control of HLW and SNF while at the same time developing an option for geological disposal so that an ongoing commitment to active management can, at some future time, be brought to an end.
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