Vulnerabilidade natural do aquífero Barreiras no município de Colares (PA): subsídios para a gestão dos recursos hídricos subterrâneos

Abstract

The vulnerability of an aquifer is related to its susceptibility to being hit by a contaminant load, interacting with its physical, chemical and biological aspects. It is in this sense of susceptibility to contamination, that the underground aquifers, associated with the growing search for quality water to meet human needs, that becomes vital the importance of identifying the possible areas of vulnerability of aquifers, whether for planning land use and occupation, or for the search for better conditions of quality and availability of groundwater. This study aimed to evaluate natural vulnerability through the Groundwater occurrence-GOWN method; Overall lithology of the unsaturated zone; and Depth of the water table) and the management of groundwater resources in the Municipality of Colares – PA, to support public decision-making. Thus, the work was carried out in the municipality of Colares, which is an island with about 250 km². The seat of this municipality is located on the shore of Marajó Bay, 93.9 km from the capital of the State of Pará, with access by highways BR-316, PA-140 and PA-238. The methodology contemplated the execution of three stages: survey of primary data, field and laboratory, in the first stage were obtained data and information necessary for the planning and execution of the other stages, in the field stage, the activities of tracking the location of the wells were developed; static level measurement of the wells used to identify the vulnerability index through the GOD method; the geographical location with the use of Global Positioning System-GPS, of potential polluters; the photographic record of the wells; the physico-chemical analysis of well water. While in the laboratory stage, the analysis of the data obtained in the field, the elaboration of the maps and the organization of the data were performed. The results of the analysis of the physicochemical parameters revealed that they are following Ordinance GM/MS no. 888/2021 that defines the potability of water and CONAMA Resolution no. 396/2008. Finally, it is concluded that the elaboration of the map of natural vulnerability to aquifer contamination can contribute to the diagnosis of groundwater quality and to assist in water management and conservation. Keywords: groundwater; god method; flow direction; environmental impact