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Radionuclide Transport Modeling of Diffusion Cell Experiments Specific to a Backfill Barrier in a Salt Repository

Published online by Cambridge University Press:  25 February 2011

Harold M. Anderson ,
John M. Pietz  and
Douglas M. Smith
Harold M. Anderson
Affiliation:
University of New Mexico, Department of Chemical and Nuclear Engineering,Albuquerque, New Mexico 87131;
John M. Pietz
Affiliation:
University of New Mexico, Department of Chemical and Nuclear Engineering,Albuquerque, New Mexico 87131;
Douglas M. Smith
Affiliation:
Montana State University, Bozeman, Montana 59717
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Abstract

Experimental radionuclide migration diffusion cell data have been collected as part of the WIPP Waste Package Performance Program. This data was collected under conditions approximating geologic isolation of a backfill barrier in a salt repository. The experiments are designed to aid in the evaluation of engineered backfill barriers.

This paper describes a radionuclide transport model designed to aid interpreting experimental diffusion cell migration data and eventually to simulate the long-term effectiveness of the backfill barrier in a salt repository. The model is designed to test a variety of expressions representative of potential mechanisms for retardation within the backfill for the best-fit with experimental data. From the comparison, the aim is to select the appropriate mechanism from the host of potential mechanisms for retardation. The model employs a novel integral equation approach to the solution of the transport equation with nonlinear retardation terms. The solution technique used in this model is a semi-analytical, iterative method for the general nonlinear problem. It is felt the technique offers improved computational efficiency over comparable finite difference methods.

Comparisons between experimental migration diffusion cell data and the model predictions are presented in this paper. Tentative conclusions concerning the importance of the retardation mechanism to radionuclide transport in the backfill barrier will be drawn.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 26: Symposium D – Scientific Basis for Nuclear Waste Management VII , 1983 , 681
Copyright
Copyright © Materials Research Society 1984

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References

REFERENCES

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