A method of pad gas management in an underground storage volume including storing a first compressible fluid, determining a transient minimum operating pressure (P trans ), measuring the pressure (P act ), removing at least a portion of the first compressible fluid, concurrently, introducing an incompressible fluid, thereby producing a transient pressure condition controlled by the flow rate of the incompressible fluid, such that P trans act. The method may also include a length of casing, permanently cemented into the surrounding rock formations, with a final cemented casing shoe defining the practical endpoint at an approximate depth (D casing ), determining a transient pressure gradient (G trans ) for the underground storage volume, wherein P trans casing x G trans. The maximum removal of the first compressible fluid is controlled such that P min act , and wherein the transient pressure condition has a duration (D) of less than 7 days, more preferably less than 5 days.