ABSTRACTDetermination of the potential of a specific confined aquifer as an effective thermal energy storage medium requires thorough knowledge of the geochemical, thermodynamic, and hydraulic properties of the aquifer and its confining layers. A series of laboratory and field studies must be performed in order to determine the fundamental parameters. Procedures and analyses of a series of tests for a confined aquifer near Mobile, Alabama were completed prior to an aquifer thermal energy storage experiment. Parameters determined were: the regional gradient; vertical and horizontal permeabilities of the storage aquifer; horizontal dispersivity of the storage aquifer; vertical permeability of the confining layers; and thermal conductivities, heat capacities, and chemical characteristics of the aquifer matrix and native ground water.