Mass-Transfer Analysis of Waste Packages Containing Defense Waste Processing Facility Glass as a Waste Form

Apted, M. J.; Engel, D. W.; ,

Mass-Transfer Analysis of Waste Packages Containing Defense Waste Processing Facility Glass as a Waste Form

by M. J. Apted, Pacific Northwest Lab, United States,
D. W. Engel, Pacific Northwest Lab, United States,

Document Type: Proceeding Paper

Part of: High Level Radioactive Waste Management 1990

Abstract:

The fractional release rates of selected radionuclides from waste packages containing Defense Waste Processing Facility (DWPF) glass are calculated using the AREST code, assuming a continuous-diffusive pathway under partially saturated conditions. One of two boundary conditions for the concentration of radionuclides at the waste-glass surface are used: 1) individual solubility limits for relatively insoluble radioelements, or 2) congruent dissolution of the glass for highly soluble radioelements. Based on available data, the radionuclides examined in this study (Tc-99, Cs-135, U-238, Np-237, Pu-239, Pu-240, Pu-242, Cm-245) are all calculated to comply with fractional release-rate limits. The major factors affecting the magnitude of predicted releases are long-term dissolution rate of the DWPF glass, radionuclide solubility, transport rate, and radionuclide inventories. The significant uncertainties regarding the appropriate values for these parameters are discussed.

Return to search