Neogene Aquifer Model

One of the key tasks of hydrogeological research at SCK•CEN is to develop a series of groundwater models (from regional to local scale) to integrate the hydrogeological knowledge and perform transport calculations in the framework of the safety calculations. These calculations are performed using the Sub-regional groundwater model which uses boundary conditions derived from the regional model. The Neogene aquifers model represents a new tool to characterise the groundwater flow in the aquifer system above the Boom clay in a better detail than the Regional model. We reproduced the observed groundwater levels using an automated calibration process. Such approach helped to estimate the optimal parameter values and identify the sensitivities of the model parameters as well as the regional hydraulic properties of the Kasterlee-Diest transition. We tested the model assumptions and analysed effects of various changes in the conceptual model. The calculations performed with the Neogene Aquifer Model validated the assumption of no flow below the Kleine Nete river. Additionally, they allowed for use of water balance analyses to validate infiltration rate used in the model. The Neogene Aquifer Model represents a modelling tool for modelling of climate scenarios providing necessary boundary conditions for more detailed performance assessment models.