Uncertainties in Nuclide Releases for a High-Level Waste Repository Backfill With Smectite Illitization

Abstract

AbstractUncertainties in nuclide release calculations, based on the uncertainty in illitization rate for smectite backfill have been studied. This paper has three new features: (i) an analytical solution with temporal parameter changes, (ii) uncertainty study with respect to the rate of temporal changes, and (iii) using various data of illitization.We show the following in this paper: (1) The uncertainty in nuclide releases is enhanced greatly in the case where the illitization period coincides with the transition time from solubility-limit source to exponentially decaying source; (2) The uncertainty in the retardation factor may have been overestimated in previous static analyses, leading to conclusions that the illitization problem is more vexing than it really is.