A suite of geoelectric techniques were used to characterize an aquifer for a pollution study. Vertical electrical soundings were used to define aquifer layer resistivities and thicknesses. Porosities, hydraulic conductivities, and transmissivities were then estimated from the resistivities and thicknesses. The mise-a-la-masse method was used to define direction of flow, tracer velocity, and dispersion coefficients. Finally, borehole logging was used to obtain additional information on porosities and velocities.