In the framework of the disposal of short-lived low- and intermediate-level radioactive waste in a near-surface disposal facility in Dessel, Belgium, additional extensive site characterization has been performed in 2008. The gathered data now enclose 388 hydraulic conductivity measurements on samples of 8 cored boreholes. Secondary information as grain size analysis, porosity, and borehole geophysical parameters was also gathered. In addition, the geology of the study area has also been thoroughly characterized by a set of 178 cone penetration tests (CPTs) to approximate 50 m depth. This dataset allowed to refine the hydrostratigraphical model of the region. The existing groundwater model, based on large-scale effective hydraulic properties, was updated accordingly. The next step is a small-scale probabilistic approach 1) to validate the current existing deterministic groundwater models and 2) to support design for a monitoring network. In preparation for stochastic realizations of the subsurface, a geostatistical analysis of the available primary and secondary data is performed.