Hydrodynamic investigations in a recent volcanic aquifer, Reunion Island, using single well tracer test

摘要

Hydrogeological investigations have been carried out on "Riviere des Rempart", south of Reunion Island, and their aim was to help the development of an area with a high potential of groundwater resources. Four boreholes already exist but inconsistent data collected from long term pumping tests compelled us to proceed to new investigations, but with the use of other methods. As fresh groundwater is poorly mineralized in Reunion Island, we performed tracer tests by means of chloride as tracer and conductivity cells for the monitoring. As natural gradient tracer tests between two wells failed, point dilution method was chosen for these tracing-tests The disappearnace of the tracer after a brief injection was monitored by several conductimetrs. Experimental data allow us to propose new hydrodynamical values (1