The semihydrostatic model permits the analytical calculation of the pressure distribution in a vertical cylindrical borehole filled with waste packages and crushed salt. The pressure components depend on the axial and radial coordinates. Two test stands of CFRP with different wall roughnesses were erected for the experimental verification of the model. The sensors manufactured for measuring the radial and axial pressures are characterized by high sensitivity, great thermal resistance and adequate stability. The measuring techniques used are capable of measuring the pressures with high axial position resolution. The investigations in the small test stand LEISA I with a smooth wall, described in this paper, show a clear dependence of the measured vertical pressures on the fine grain fraction of the bed. The vertical pressures rise with increasing fine grain fraction. A correlation between the pressures and the densities of the respective grain fraction cannot be observed. The lateral pressure coefficients are determined from the radial and vertical pressures measured. They can be used together with the measurements of the wall friction coefficients in a shear apparatus to calculate the pressure distributions. There is good agreement between measured and calculated pressures. This agreement will further improve when a bottom plate with differently arranged vertical pressure sensors is completed and a lambda meter is built for exactly measuring the lateral pressure coefficient.