Tracer tests are of main importance to understand the behaviour of solutes at hydrological systems.
In low permeability fractured media, performance of such tests becomes difficult due to the low flowrates achivable, to ensuring that solutes are effectively injected and to the complex characterization of the geometry of these systems, among others. Limitations set constrains to the data thus obtained, which in turn, are difficult to interpret. Therefore, tests have to be performed under extremely controlled conditions.
In this article we present the applied methodology in a granitic rock mass in the frame of El Berrocal project (planning, development, performance and Interpretation)