A modular fuel dispensing and containment assembly for storing fuel in at least one fuel tank and for pumping the fuel to a group of fuel dispensers. The assembly has a reinforced concrete vault located underground which contains a fuel tank within its interior. The fuel tank is separated from the interior walls of the vault. The fuel tank has a turbine corridor on its lid, which corridor has an interior volume which leads from the fuel tank to a series of piping corridors. The turbine corridor and the piping corridors are all underground and the piping corridors lead to dispensing modules which are located under the dispensers or gas pumps. The dispenser modules and piping corridors are all sufficiently large to permit the entry of service personnel to their interiors. The interiors of the various corridors and modules form a single interconnected air volume. The result is a fuel dispensing and containment assembly wherein the vault and corridors and dispensing modules act as a secondary containment against any contaminant leaking from the primary piping or tanks. It also permits complete visual inspection of the primary containment and physical access to all its parts at any time.