Geochemistry water of the Camaquã das Lavras and Hilário streams, Lavras do Sul-RS: anthropogenic or natural?

Abstract This article presents the first detailed geochemical data of the water from Camaquã das Lavras and Hilário Streams from Lavras do Sul-RS. Geochemical and statistical analyses were used in this study to establish the anthropogenic or natural influence on the region. The results classified the waters as soft and intermediate with acidic and neutral pH. The electrical conductivity varies from 37.2 to 62.9 μs cm-1 and the total alkalinity ranges from 4 to 30 mgL-1. The distribution patterns and ratios indicate that clay mineral weathering is dominant on the investigated samples. It is followed by feldspar weathering in an environment under temporary hardness conditions. Cu, Rh, and Cd enrichment is associated with the many mineral deposits of the region, lithological diversity and human activities. All the measured values conform with the standards set by Brasil-Ordinance nos. 2914/2011, 36-GM/1990 and 1469/2000.