An Instant-Release Source Term For The Assessment of Used Nuclear Fuel Disposal

Abstract

Instant-release fractions are estimated for the potential release of radionuclides from used CANDU fuel in a geological disposal vault, taking variability and uncertainty into account. The radionuclides discussed in this paper are 129I, 135Cs, 99Tc, 79Se, 126Sn, 90Sr, 14C and 3H. The


instant-release fractions are based on experimental data on the short-term release of radionuclides from used fuel upon contact with groundwater and on fuel-performance calculations. Using these instant-release fractions, we derive and present source terms for the environmental and safety assessment of used nuclear fuel disposal.