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The Modification and Application of the Geochemical Modelling Code CHEQMATE to Simulate Transport and Chemical Processes within Fractured Media

Published online by Cambridge University Press:  25 February 2011

A. V. Chambers  and
A.C. Smith
A. V. Chambers
Affiliation:
AEA Technology, Decommissioning & Waste Management, 424.4 Harwell, Oxon OX11 0RA, UK.
A.C. Smith
Affiliation:
AEA Technology, Decommissioning & Waste Management, 424.4 Harwell, Oxon OX11 0RA, UK.
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Abstract

The UK current plans for a repository for the disposal of intermediate-level radioactive waste involve the use of a cementitious backfill within the repository vaults. Radionuclide transport could be concentrated within cracks that may form in the cement, or in fractures within the rock surrounding the repository. A version of CHEQMATE (CHemical EQuilibrium with Migration And Transport Equations) that includes a representation of transport through fractured media has been developed. This paper describes modifications of the code, to allow simulation of transport through either a single fracture, or, by adopting a continuum approach to represent fracture distribution, through multiple fractures. Successful verification of the modified program against analytical solutions for transport through fractured rock and cracked cementitious media is presented. An application of the modified program to study the evolution of the aqueous chemistry within a repository vault containing a single fracture through the cementitious backfill is also discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 333: Symposium V – Scientific Basis for Nuclear Waste Management XVII , 1993 , 855
Copyright
Copyright © Materials Research Society 1994

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References

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