The clay extraction in the area of the so-called Mühlenberg started in 1982, reached a depth of nearly 15 m below the ground level and has already been completed in the meantime. Since then the site is backfilled with non-hazardous mineral substances. Whereas in some places backfilling still takes place, in other places surface sealing was already applied and recultivation has started. Large surfaces were already recultivated since 2013 and indigenous deciduous forests e. g. beeches and oaks were already planted. The designation Mühlenberg, which is more a hill than a mountain, results from the fact that the backfill was also accompanied by a ground elevation which - once recultivation has been completed – will harmoniously fit into the landscape. The authorisation expires in 2023, therefore at latest the entire surface will be recultivated until such time.