As part of the MuSE project, Professor Dr Rudolph and his team are focusing on the economic and technical (re-)assessment of polder management by means of multisensor geomonitoring. Dr Xiaoxuan Yin, a specialist in the field of radio interferometry and remote sensing, joined the Research Center of Post-Mining for the project and explains the approach: ‘We use various sensors to measure the ground moisture. At the same time, we evaluate data in the areas surrounding the two most recently active mines in the Ruhr area, Prosper-Haniel in Bottrop and Auguste Victoria in Marl, and explore the vegetation with our drones. We compare the information at the sites with remote sensor data from the European Copernicus satellite programme and are evaluating them for the first time for this issue.’ Dr Yin combines the many different sources of information in a 4D model with time as the fourth dimension. This enables the tracing and digital modelling of the changes of the water balance and their effects on the environment over the decades.