During the months of September 2023 to July 2024, groundwater samples were collected at 10 sampling sites, distributed in the Sector Oeste neighborhood, in the city of Paraíso do Tocantins, state of Tocantins, with the aim of assessing the quality of groundwater captured in tube wells potentially used for human consumption. For all the groundwater samples, the physicochemical parameters ammonia, chloride, apparent color, hardness, nitrate, nitrite, pH, turbidity and microbiological total and thermotolerant coliforms were analyzed. Based on these results and in order to better understand the physicochemical behavior of these waters, principal component analysis (PCA) was used to carry out a more complete evaluation of the original data. The physicochemical and microbiological parameters assessed in the groundwater collected showed that 90% of the wells had pH values below those recommended in Ordinance GM/MS No. 888/2021 and the presence of total and thermotolerant coliforms in all the water samples from the wells analyzed, which is in disagreement with the legislation. In addition, the PCA explained 49.84% of the total variance of the data, making it possible to assess the degree of similarity between the samples. It is important to have more reliable monitoring and assessment of groundwater in cemetery areas and prior knowledge of the chemical composition of this water, as this is the only way to assess whether any parameter is altered, even if its concentration is equal to or lower than that considered naturally occurring by current legislation.
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