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Development of a New Mechanistic Low-Level Waste Source TermModel

Published online by Cambridge University Press:  03 September 2012

Man-Sung Yim
Man-Sung Yim*
Affiliation:
Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695
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Abstract

A new mechanistic low-level waste source term model was developed. Keyfeatures of this effort are: use of cumulative probability functions todescribe the failures of waste containers; capability to describe diffusioncontrolled release which is dependent on the conditions of the waste packagesurroundings; consideration of the effects of gas generation on the sourceterm, and; use of a source inventory characterization routine to provide abuilt-in capability for defining the distributions of radionuclides invarious waste forms and streams. The model is capable of describing thediffusion of radionuclides in waste forms with the use of concentration andflux continuity boundary conditions. Release of radionuclides from variouswaste streams is modeled by the combination of diffusion, dissolution, andsurface release. Failures of waste containers are portrayed by the use ofprobabilistic failure functions based on Weibull and lognormaldistributions. The model for radionuclide release from waste packages iscoupled with the near-field transport model to describe the effects ofmigration and dispersion within the disposal unit. Characteristics of thenew model were evaluated through sensitivity analysis and compared withexisting source term codes.

Information

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 465: Symposium II – Scienfific Basis for Nuclear Waste Management XX , 1996 , 1059
Copyright
Copyright © Materials Research Society 1997

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References

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