VULNERABILITY INDEX OF GROUNDWATER IN THE MUNICIPALITY OF ROSARIO DO SUL, RIO GRANDE DO SUL

This research is part of integration award of instruments, and collection guidelines for the management of groundwater Project. The objective of this work was to study the groundwater vulnerability of the Rosario do Sul city, in Rio Grande do Sul state, southern Brazil on the edge of the Parana Basin. It is part of the outcrops zone (ZA) Guarani Aquifer System (GAS). This aquifer is porous, unconfined, intergranular, unconfined belonging to Piramboia Formation. Was estimated the aquifer pollution vulnerability index map using the GOD methodology adapted to Brazilian conditions. Were developed a database of 35 tubular wells associated with the hydrogeological characteristics of the overlying vadose zone necessary to use. Was considered groundwater hydraulic confinement, overlying strata and the depth to groundwater table. The range of the vulnerability Index was High (40.00%), followed Moderate (28.57%), Low (14.29%), Extreme (14.29%) and Negligible (2.85%) from the total studied area.