Analytical Solution for Constant-Rate Pumping Test in Fissured Porous Media with Double-Porosity Behaviour

An analytical solution for constant-rate pumping test in fissured porous media is developed using the dual porosity approach with pseudo-steady state exchange between fissures and matrix. It is shown how the solution relates to other pumping well functions. For analyses of pumping tests, type curves are presented that enable to estimate aquifer transmissivity, storage coefficients of the fissures and matrix and conductance for fluid exchange between the fissures and matrix. The analytical solution is also linked to a non-linear least squares optimisation algorithm to automatically fit simulated and observed drawdown and estimate hydraulic properties of the aquifer. The usefulness of the method is demonstrated by a practical application using data described in literature from a pumping test conducted in a confined limestone karst aquifer. Results obtained for the aquifer parameters estimates including 95% confidence intervals demonstrate the practical usefulness of the obtained solution.