Determination of the hydrogeological parameters of a tilted confined aquifer by slug tests

The effect of the dip of an aquifer on the hydrogeological parameters of a tilted confined aquifer was evaluated by slug tests. Using the Kipp model, an analytical solution model was derived for the slug tests considering the dip of the tilted confined aquifer. When the dimensionless storage coefficient and inertial parameter were constant, the dimensionless damped coefficient of the test well-aquifer system increased with increasing dip. When the dimensionless damped coefficient calculated by the modified model differs by 10% than the value calculated by the Kipp model, the effect of the dip should be considered, and the critical dip for affecting the water head response was 34°. The difference in the analytical results between the modified and Kipp models indicates that ignoring the dip of aquifer will cause error in the estimation of the transmissivity and storage coefficient of the tilted confined aquifer.