In this study, non-destructive methods are applied to quantify the influence of concrete degradation by geologic conditions on the ability to retain nuclear waste deep underground in The Netherlands. Nuclear reactors play an important role in all four scenarios of the recent report of the IPCC to reach the CO2 reduction goals. Safety related criticism against nuclear energy technology are less relevant for Generation IV nuclear power plants, of which several are scheduled to be constructed in Europe within the next few years. This is partially due to the inherent safety features of Gen IV power plant designs, where disasters experienced before (e.g., Chernobyl, Fukushima) are technically impossible. Concrete samples provided by COVRA are degraded by immersion in a solution that contains chlorides and sulphates in concentration levels that are similar to geologic conditions. The influence of concrete degradation on the internal structure of concrete has been investigated using X-ray and Neutron radiography. Pore size distributions, pore geometry and sorptivity are presented. In order to validate the results, standardized tests are performed and the results are compared.