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Underground Criticality in Geologic Disposal1

Published online by Cambridge University Press:  03 September 2012

J-S Choi
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
T. H. Pigford
Affiliation:
Nuclear Engineering Department, University of California, Berkeley, CA 94720
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Abstract

Disposition of weapons fissile material as once-through MOx fuel in reactors or immobilization in waste glass would result in end products requiring geologic disposal. Similar considerations apply to some spent fuels in a geologic repository. The criticality potential of these end products in a geologic setting is an important consideration for the final disposal of these materials. In this document we present calculations that help define parameters and configurations for criticality, including those that, if the criticality is achieved, could lead to autocatalytic power transients. It is not the purpose of this paper to define scenarios that could reasonably lead to criticality or to establish the probabilities that critical configurations could occur. We do suggest some parameters that should be considered by waste package designers and repository analysts to ensure that criticality cannot occur.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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Footnotes

1

This is an independent study by the authors. It is not associated with Lawrence Livermore National Laboratory.

References

REFERENCES

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