The stability and integrity of salt rock caverns for Underground Energy Storage (UES) are commonly assessed through finite element calculations. The geometrical model is based on sonar-mapping of the cavern contour. However, this technique misses the large space occupied by insoluble sediments at the bottom of the cavern called the sump, which leads to a misrepresentation of the geometry in particular in bedded salt formations with a high content of insolubles. In this article, solution mining simulation is employed to reconstruct the sediment-occupied space, which is then integrated with sonar-mapped data to form three comprehensive “full-geometry” models of caverns JT52, JT86 and JT103 in Jintan, China. Finite element analyses are conducted on these models and compared with “sonar-scanned” models that neglected the sump. The simulation results show that, compared with the ”sonar-scanned” models, the volume shrinkage value of the full-geometry model increases by 18.1 %, 30.5 % and 13.7 % for JT52, JT86 and JT103, respectively. The total volume of the damage zone increases by 15.7 %, 19.3 % and -22.0 %, respectively. Consequently, neglecting the sump can make stability and integrity assessment results either more or less conservative. Therefore, it is recommended that stability and integrity analysis of storage salt caverns consider the sediment-occupied sump below the sonar-mapped cavern floor in bedded salt.