Identificação e seleção de áreas potenciais à implantação de aterro sanitário no Município de Castanhal-PA, através do uso de sistema de informações geográficas

Abstract

Solid urban waste is a social and environmental concern. The difficulty in finding areas for their deposit, since the generation and deposition are daily activities of the population, presents itself as a problem. In this sense, the present work sought to identify and select, one or more areas apt to receive the implantation of a Landfill in the municipality of Castanhal - PA. For the determination of the area, able to receive the enterprise, the use of Geographic Information Systems is paramount. When using Geographic Information Systems to analyze a range of socio-environmental factors, stipulated by the Laws and Norms, the multicriteria analysis method becomes essential for the execution of the work. This method made it possible to elaborate thematic maps from vector, tabular and rasters data, which allowed to illustrate, manipulate and analyze the necessary criteria. These criteria were classified as Staggered or Restricted, in which the Staggered criteria consisted in weighing the degree of importance of each variable, through the assignment of notes and weights. The Restrictive criteria were based on areas that can not be considered fit under any circumstances, and should be excluded. Therefore, the aptitude calculation was performed, which assigned scores from 0 to 5, according to the degree of potentiality of each area, such that areas with scores above 4.5 were considered to be excellent at receiving the landfill. For the sizing of the area, required for installation and operation of the landfill, it was stipulated 20 years as the useful life of the landfill. Thus, using the arithmetic projection formula, the population of the municipality of Castanhal was estimated, followed by the estimated generation of waste for the same period (2019 to 2038). Therefore, it was defined that to meet the demand of the municipality during the stipulated period, a minimum area of 35 hectares would be required. Thus, among the areas considered eligible to receive the landfill, 6 areas were selected, with a size equal to or greater than 35 ha. In on-site validation, only areas 1 to 5 confirmed their physical fitness, becoming fit for study. Finally, the study elucidated the importance and the efficiency of the application of Geographic Information Systems in socio-environmental projects in the Amazon.