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Discrete-Fracture Modeling of Thermal-Hydrological Processes at Yucca Mountain and the Llnl G-Tunnel Heater Test

Published online by Cambridge University Press:  15 February 2011

John J. Nitao  and
Thomas A. Buscheck
John J. Nitao
Affiliation:
Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551
Thomas A. Buscheck
Affiliation:
Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551
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Abstract

An in situ heater test was performed at G-Tunnel, Nevada Nuclear Test Site, to investigate the thermal-hydrological response of unsaturated, fractured volcanic tuff under conditions similar to those at Yucca Mountain. The NUFT flow and transport code was used to model the test using discrete-fracture and equivalent-continuum approaches. Nonequilibrium fracture flow and thermal buoyant gas-phase convection were found to be the likely causes for observed lack of condensate imbibition into the matrix. The potential repository at Yucca Mountain was also modeled. Disequilibrium fracture flow is predicted to occur for less than a hundred years after emplacement followed by a period of fracture-matrix equilibrium, during which the equivalent-continuum and discrete-fracture models give almost identical results.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 412: Symposium V – Scientific Basis for Nuclear Waste Management XIX , 1995 , 747
Copyright
Copyright © Materials Research Society 1996

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References

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