| This study assessed parametric uncertainty of flow and transport parameters of the unsaturated zone at Yucca Mountain and its propagation in unsaturated flow and radionuclide transport using the Monte Carlo method. The random fields of hydraulic parameters (matrix porosity, permeability and sorption coefficient) were generated using the Latin Hypercube Sampling (LHS) method and used as inputs to a three-dimensional flow and transport code, TOUGH2 developed by the Lawrence Berkeley National Laboratory. By running TOUGH2 for multiple parameter realizations, means, variances, 5% and 95% percentiles of flow and radionuclide transport simulations were estimated to quantify the optimum predictions and associated predictive uncertainty. The results indicated that the parameter uncertainty in matrix porosity, permeability and sorption coefficient had significant influences on the simulated groundwater flow and radionuclide transport in the unsaturated zone at Yucca Mountain. |
