ANALYSIS OF AQUIFER TESTS CONDUCTED IN FRACTURED ROCK: A REVIEW OF THE PHYSICAL BACKGROUND AND THE DESIGN OF A COMPUTER PROGRAM FOR GENERATING TYPE CURVES

Abstract. Assessing the hydrogeological character of fractured bedrock between two or more wells is usually accomplished through an analysis of the results of traditional pumping tests. Because these tests are subject to field boundary conditions that may be different from those conducted in porous media, alternative testing techniques or analytical methods are required. To provide an adaptable interpretive package for analyzing interwell hydraulic tests in fractured rock, a FORTRAN program was developed to generate type curves for pumping tests and pulse interference tests. A review of the physical conditions which most influence the results of these tests is conducted to provide the background for the development and use of the program. The analytical solutions included in the program consider inner boundary conditions such as wellbore storage, infinitesimally thin skin and finite-thickness skin. In addition, a solution is included to analyze results influenced by wellbore storage and infinitesimally thin skin at both the pumping and observation wells. The solutions are given in the Laplace domain and are numerically inverted to generate data for the type curves. The curves can be plotted using any standard plotting program, or they can be plotted manually. The program is menu driven, easily adaptable to include additional solutions, and can be executed on a personal computer.