Risco de contaminação pela presença de disposição final de resíduos sólidos urbanos em bacias de captação superficial de água para abastecimento público no estado de Goiás

• Autor(a) principal: Pinheiro, Roberta Vieira Nunes
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/7172
• topic: Contaminação por lixiviado; Disposição final de resíduos sólidos urbanos; Qualidade das águas de abastecimento; Vulnerabilidade ambiental; Leachate contamination; Urban solid waste disposal site; Water supply quality; Environmental vulnerability; ENGENHARIA SANITARIA::SANEAMENTO AMBIENTAL

Vulnerability models are important tools in the study of water contamination by different soil usage activities. The goal of this research is to evaluate the risk of contamination by the presence of an urban solid waste disposal site (UWDS) within the surface water catchment basins (SWCB) used in the State of Goiás public water supply. An identification and characterization of the SWCBs and UWDSs has been carried out in a geographical identification system using the QGis 2.12.0 – Lyon software. Afterwards the overlapping of this information allowed the identification of all SWCBs which had an UWDS within its limits. A Susceptibility Index (SI) was applied to these SWCBs. The SI was formed by intrinsic characteristics such as the depth of a non-saturated zone, net recharge, aquifer material and topography. Also contributing to the SI was an extrinsic characteristic, soil usage. The comparison and identification of the dominant classes of the SI was done through the calculation of the average vulnerability of each SWCB. The SWCBs, which had the highest risk of water contamination were selected and had the UWDSs in its areas analyzed by six technical parameters: type of UWDS, estimate of waste generation, surface area, slope, SI of the UWDS and its distance to the nearest body of water. Each parameter was classified according to its risk to water contamination and given a scale from 1 to 7. The given values were correlated evaluating the interdependence of the parameters. The use of this method led to the identification of 204 catchment points and its SWCBs and 228 UWDS, out of which 93% were irregular dumping sites. The SI for each of the 43 SWCBs identified in the State in which there was the presence of 69 UWDSs, was then calculated. The average vulnerability for each SWCB allowed the selection of the 9 most vulnerable ones. These were distributed in the high-to-moderate and moderate-to-low classes (SI > 50), which had 18 UWDSs within its limits. A Spearman analysis was done using the coefficients attributed to each parameter of the UWDSs. The analysis permitted the identification of only 2 parameter with significant correlation (surface area and estimate of waste generation). This confirmed the interdependence of the selected characteristics. It also allowed for a risk calculation through the addition of the parameters, which ranged from 15 to 27. These were distributed into three classes (low, medium and high). The high risk UWDS identified were in the cities of: Bom Jesus de Goiás, Itumbiara, Jataí e Rio Verde. The surface area, waste generation and slope were the parameter which most influenced this classification. In conclusion, the vulnerability evaluation proved effective, and of great relevance in the identification of the SWCBs most susceptible to water contamination. It can also be applied to other study areas. In Goiás, the analysis allowed the existing risk calculation for each of the 18 UWDSs out of which 4 were classified as high risk. These were considered priority adequate and remediation sites.