USE OF RADON AS WATER TRACER AT JUATUBA BASIN

Abstract

For the last thirty years, several researches have been developed at Juatuba representative basin, located at the southeast region of Brazil, including the use of natural (tritium), fluorescent (rhodamine and fluorescein) and radioactive (technetium 99) tracers, to investigate and solve many hydrological problems. The goal of this paper is to present a research done at Juatuba basin, in order to look for discharge sections at the Fundão stream, using radon as natural tracer, to identify connections between surface and underground waters. The RAD7 equipment, which measures the concentration of radon in waters, was used to analyze water samples at different points, in three campaigns. After the identification of the sections were the radon had the biggest concentrations, a scan of two stretches was done, and the flows were measured with the help of the Flow Tracker device. The results showed a difference between the flows upstream and downstream, which associated to the peaks of the concentration of radon indicates the presence of a discharge zone.