Rock mechanics investigations serve to prove the stability and tightness of the storage during its entire life cycle. This is done through complex rock mechanics calculations and simulations. Thermodynamic simulations make it possible to investigate even complex storage scenarios and optimise operating methods. The long-term behaviour of the cavern with regard to convergence and possible effects on the surface can also be shown. Tectonic lowering analyses and backfilling/plugging concepts are thus also part of the overall rock mechanics concept and round off the spectrum of this special field.