This thesis deals with the extension of the quarry “Fischbach” in Upper Bavaria. In this mining site Wettersteinkalk is derived primarily, which is transported to the process of cement production to Rohrdorf. For the planned expansion first a geotechnical mapping of all benches was made. Here all the benches are divided into segments, and then taken gap data. In addition, rocks samples are taken from the mining area, which are further processed into Rohrdorf cement laboratory for rock specimens. Then uniaxial compressive tests carried out, and thus determines the parameters of the unconfined compressive strength. This data forms the basis for a differentiated geomechanical classification of the benches and slopes. The rock classifications result in further consequence values for cohesion and angle of friction, and thus define the rock strength of individual bench-areas. Furthermore, the slopes are tested in actual condition and after enlargement on stability. This happened on the one hand through a regional breakdown, in which several benches can failure along slip circles, on the other hand through a local viewing on benches, wherein at each bench-segment a wedge failure is assumed by intersecting gaps. This stability considerations give factors of safety for a given slope height, or permit with an assumed factor of safety secure slope height. Next, a deposit model in the software "Surpac" is created for the mine planning. In this model, an interface between the two lithologies "Wettersteinkalk" and the overlapping “Raibler Schichten” is created by using the data of incurred exploration drilling. The result is a single 3-dimensional body either for Wettersteinkalk and for Raibler Schichten. As a final step, a mining plan for different time intervals is created with these bodies. This plan provides information on the geometry and accessibility of the extended quarry area, and also provides information on how many tons of rock which can be won per degradation step.