Evaluation of Uncertainties Related to the Near Field Model of Geological Repository for Spent Nuclear Fuel

Dana Barátová, Vladimír Nečas

Institute of Nuclear and Physical Engineering,Slovak University of Technology in Bratislava, Slovakia.

DOI: 10.4236/wjet.2015.33C024                

Abstract

In Slovakia, a direct disposal of spent nuclear fuel in a deep geological repository within the country after a certain period of interim storage is a preferred option. This paper briefly describes near field model of radionuclide migration developed in GoldSim simulation code environment and analyses the calculated results on time-dependent release rates of safety relevant radionuclides. Given the fact that GoldSimalso enables to perform probabilistic simulations using the Monte Carlo method, a probabilistic approach was chosen to assess the influence of selected near field parameter uncertainties related to radionuclide migration on the radionuclide release rates from the bentonite buffer to the surrounding host rock. Based on the results, release rates of nuclides which exceed their solubility limits are effectively lowered and many of nuclides are significantly sorbed on the buffer material. It can be seen that the variance of the total release rate in the case of solubility uncertainty is almost two orders of magnitude within a long period of time.

Keywords

Geological Disposal, Near Field Model, GoldSim, Uncertainty, Probabilistic Simulation

Conflicts of Interest

The authors declare no conflicts of interest.

References

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