Avaliação da composição hidrogeoquimica de águas subterrâneas de poços profundos situados no município de Caucaia-CE e suas limitações de usos

Abstract

The use of underground water resources in northeastern Brazil is an important alternative for meeting multiple uses. However,the quality of this type of water is conditioned to a series of physical-chemical parameters, often providing little information when analyzed in isolation. In this context, this study had as objective to evaluate the hydrogeochemical composition of the water of five deep wells in the Municipality of Caucaia -CE through ionic indexes and reasons aiming to evaluate the limitations ofuses of this type of water. The results obtained showed that the samples have high electrical conductivity (2935 to 8350uS/cm) and are classified as very hard water (> 300mgCaCO3/ L). The indexes studied show that the waters have a tendency to corrosion and are classified as chlorinated sodium. In addition, the analyzed samples have a degree of restriction in relation to sodicity classified as high risk (average RAS> 18) and the samples represent a risk of soil salinization ranging from very high (2250uS /cm< EC< 5000uS/cm ) and exceptionally high (> 5000uS /cm). Thus, the use of these waters for drinking purposes presupposes a treatment aimed at removing mainly high concentrations of salts and in irrigated agriculture the need for specific management techniques for the use of waters with these characteristics.