Avaliação da qualidade da água de consumo humano em poços subterrâneos de propriedades rurais do município de São José do Inhacorá – RS

Abstract

The present study aimed to evaluate the potability of water, for human consumption, extracted from underground wells located in the municipality of São José do Inhacorá - RS, in a period of four months (May to August/2021). Chemical, physical and biological analyzes were carried out on water samples collected from three rural properties in the municipality. The results obtained were compared with the parameters established in Ordinance GM/MS nº. 888, of 2021, and by the World Health Organization, of 2017. According to the results obtained, the variables turbidity, nitrite, fluoride, total hardness and apparent color are in accordance with Brazilian and global legislation. The variables total alkalinity and electrical conductivity, which were also monitored, do not present maximum values allowed in current legislation. Regarding the variable total iron, it is not in compliance with current legislation. In terms of the pH variable, only the water from the well of one of the three properties does not comply with Brazilian legislation. The analyzes showed that the biological variables (total coliforms and Escherichia coli) detected in the water samples from the wells of two of the properties of the study are in disagreement with the legislation, and this result may be associated with the high rainfall that occurred in the sampling period. The macroscopic analysis was carried out around the wells of the three rural properties and classified according to their degree of preservation, with two results being poor and one reasonable. Based on the monitoring carried out during the sampling period, it is clear how much human activities, climatic events and the lack of protection around the underground wells influence the potability of water, since all properties were lacking in treatment and devoid of of ideal protections in the vicinity of the wells. Therefore, as a result of the study carried out, it is suggested that the disinfection of the waters of the analyzed underground wells be carried out, through the use of chlorination, as well as it is proposed that the protection in the surroundings of the investigated wells be increased, so that the achieve better water quality indices, without posing risks to human health.