The present paper shows studies aiming groundwater vulnerability evaluation in Campos dos Goytacazes region, Rio de Janeiro, Brazil. The Aquifer Vulnerability Index (AVI) was the vulnerability method applied, using Geographical Information System tools. The AVI Method has adopted the concept of hydraulic resistivity (sum of taxes among unsaturated thickness and hydraulic conductivity). Result maps showed that the region has groundwater vulnerability to contamination from high to extreme levels. The vulnerability varied from "High" to "Extremely high" indexes (from 0-10 days to 10-100 days, respectively). This high vulnerability was attributed to the occurrence of high permeability formations (sands) and shallow water table, typical from the delta of Paraíba do Sul river. High vulnerability index terrains are situated in the following areas: (1) along the right and left banks of Paraíba do Sul river, (2) in the west side of the study area (region of Muriaé and Paraíba do Sul rivers confluence), and (3) in the east side of urban area of Campos dos Goytacazes. The Extremely high index areas are located: (1) in the north portion (Barreiras aquifer), (2) in urban area of Campos dos Goytacazes, besides Saturnino Braga and Mucurepe districts, (3) eastern region of the studied area, (4) in a portion area between Cambaíba and Andreza water drainage channels, and (5) in terrains situated in the south portion of the area (Feia lake). These results showed an important environmental parameter in the river delta region, intending to subsidized public policies to preserve, to protect, and to sustain this important groundwater resource.
groundwater vulnerability; aquifers; Aquifer Vulnerability Index (AVI); Campos dos Goytacazes; Geographical Information System
