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The Effect of Precipitation Fronts Induced by Radionuclide Chain Decay and Elemental Solubility Limits on Near-Field Mass Transport

Published online by Cambridge University Press:  25 February 2011

Karen J. Worcan
Affiliation:
Intera, Environmental Division, Denver, CO 80235
Michael J. Apted
Affiliation:
Intera, Environmental Division, Denver, CO 80235
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Abstract

The formation and impact of precipitation fronts on the diffusional mass transport of radionuclides from a high-level nuclear waste canister through a bentonite buffer has been investigated in a series of numerical simulations. The precipitation fronts arise from chain decay and ingrowth, coupled with differences in elemental solubility limits and sorption properties. The fronts influence particularly the behavior of uranium, plutonium and neptunium isotopes. The isotopic concentration profiles across the buffer differ considerably from results obtained with models that employ elemental solubility limits simply as a boundary condition at the waste-bentonite interface.

Type
Research Article
Copyright
Copyright © Materials Research Society 1992

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References

REFERENCES

1. SKBF/KBS, Final Storage of Spent Nuclear Fuel-KBS-3, (i) General, Geology, (iii) Barriers, (iv) Safety, 1983.Google Scholar
2. SKI Project-90, Summary, Volume I and Volume II, SKI-TR 91:23, August 1991.Google Scholar
3. Garisto, F., Solid Dissolution: Effect of Mass Transport-Precipitation Coupling, Chemical Engineering Science, Vol. 41, No. 12, 1986.Google Scholar
4. Chuang, G.M., A Two-Dimensional Finite Element Model Study of the Near-Field of a High-Level Radioactive Waste Repository, Ph.D. Thesis, University of Washington, June 1991.Google Scholar
5. Robinson, P.C. and Worgan, K.J., Radionuclide Migration Modelling in CALIBRE, SKI-TR 89:9.Google Scholar
6. Shaw, W.T., The Motion of a Redox Front in a System of Bentonite and Rock, SKI-TR 89:8Google Scholar
7. Performance Assessment Center for Engineered Barriers (PACE) Program: Volume 1: Near-Field Performance Analysis, PNC PA0865 91-001, March 1991.Google Scholar
8. K.J. Worgan, Comparison Exercise Using the Source Term Models CALIBRE and STRENG, Intera Sciences internal draft report, IM2704-1, Version 2, May 1991.Google Scholar