Methodology of Safety Assessment and Sensitivity Analysis for Geologic Disposal of High-Level Radioactive Waste

Abstract

A deterministic safety assessment methodology has been developed to evaluate long-tern1 radiological consequences associated with geologic disposal of high-level radioactive waste, and to demonstrate a generic feasibility of geologic disposal. An exposure scenario considered here is based on a normal evolution scenario which excludes events attributable to probabilistic alterations in the environment. A computer code system GSRW thus developed is based on a non site-specific model, and consists of a set of sub-modules for calculating the release of radionuclides from engineered barriers, the transport of radionuclides in and through the geo-sphere, the behavior of radionuclides in the biosphere, and radiation exposures of the public.

In order to identify the important parameters of the assessment models, an automated procedure for sensitivity analysis based on the Differential Algebra method has been developed to apply to the GSRW.

KEYWORDS:

• radioactive waste disposal
• high-level radioactive wastes
• safety assessment
• source term
• geologic media
• radionuclide migration
• solubility
• decay chain
• groundwater
• sorption
• advection
• dispersion
• biosphere
• automated sensitivity analysis