It is difficult to determine the coefficients of groundwater flow from the data which were obtained from the
drawdown test in a multiaquifer system. In this paper, new methods of analyzing drawdown-tests are developed and illustrated with the example to determine aquifer coefficients. In a double-layered aquifer, the analytical solution of drawdown test, in which water is discharged from both layers, is derived. And also the theoretical solution to determine the coefficient of storage by using an index of elasticity of a confined aquifer is derived.
From these solutions, methods of determining the coefficient of transmissibility in a double-layered aquifer
and the coefficinent of storage in a confined aquifer are
got. The example analysis to determine aquifer coefficients
is shown. As a result, the characteristics which were
obtained by these methods are verified by the real drawdown