Modelling of safety relevant processes for nuclear waste disposal

A short survey is given on the modeling of individual processes which must be considered in long term safety analyses for nuclear waste repositories. Four examples of modeling efforts at INE in this field are presented: Thermomechanical model calculations for the TSS in situ experiment with the major aim of model validation; coupled calculations on brine flow and dissolution/precipitation effects in salt as part of a HLW borehole scenario; thermodynamical studies on the uranium(VI) solubility in the geochemical environment of a repository for cemented low level wastes; model calculations and code verification for migration of radionuclides in aquifers under consideration of different sorption models. (orig.)