After a power outage, a client became concerned about long-term backup of their data center. The client decided to add a backup generator with a large fuel tank in an underground parking structure. However, building codes can be quite strict about storing large amounts of fuel inside a parking structure. The selected design required heavy walls to contain the generator and fuel tank. The proposed loading was much higher than the structure could support. However, limestone bedrock was located just a few feet below the building structure in one location. So the structure was modified so that the tank could be directly supported on the bedrock instead of requiring expensive modifications to the structural steel beams. Special safety bollards were also designed to protect the fuel tank enclosure from vehicle collision.