Avaliação de vulnerabilidade e perigo à contaminação das águas subterrâneas do município de Caçapava do Sul – RS

Abstract

Due to the lack of licensing and environmental acessment, several projects were implemented in the city of Caçapava do Sul, without complying with environmental requirements. Some activities are using substances and compounds and they are incorrectly discarded, offering high potential of contamination of the soil and groundwater. That is to say, the present work has the objective of evaluating the conditions of vulnerability and danger of contamination of the groundwater in said municipality. For this, the GOD methods were applied, (G = Confinement level, O = Occurrence of geological strata and D = Distance of water level) and POSH (Pollutant Origin and its Surcharge Hydraulically). The methodology consisted in the collection and treatment of data on the wells of abstraction of municipal groundwater, through the data available in the SIAGAS digital platform. The data were interpolated by the software QGis 2.18, generating maps of vulnerability indexes which reflected the situation of the territory studied. The results, by the application of the GOD method, showed predominance of the medium, high and extreme vulnerability class in all municipal extension. While, the POSH method highlighted as high potential contamination activities: gas ststions, mechanical workshops, mining and lack of sewage treatment. This work presented the unfavorable conditions, referring to the high vulnerability indexes of contamination in the area of the local aquifers. Finally, it was highlighted the need for the competent governamental agencies to carry out more detailed studies for possible preventive, corrective, and remediation actions and to inspect these areas, aiming at the best use and management of groundwater.