Permeabilidade e condutividade hidráulica do solo em área de descarte irregular de resíduos sólidos no município de Caçapava do Sul - RS

Abstract

Currently, the production of large volumes of waste is one of the biggest problems faced by public managers, and this is aggravated by the uncontrolled population growth and technical precariousness of the agencies responsible for waste management. With the increase in waste production, the disposal of waste in irregular areas also increases, such as open-air dumps. One of the main problems related to the use of irregular areas for waste disposal is soil contamination by leachate, which comes from the decomposition of organic matter, and can cause numerous environmental impacts. In this context, it is clear that there is a need to characterize these areas in order to determine whether pollutants are percolating through the soil and reaching deeper layers and the water table. The study area is located in the municipality of Caçapava Do Sul - RS, and is characterized by having been a site of irregular disposal of solid waste, mainly from construction. In addition, the location is close to urban agglomerations, which can lead to several health problems for the people who live there. To characterize the soil, tests were performed to measure granulometric analysis, soil and particle density, and total porosity. Permeability was determined in field tests using a Guelph permeameter. Saturated hydraulic conductivity was determined through laboratory tests using a constant-load permeameter. Based on the data obtained and statistically analyzed, it was determined whether the permeability parameters were within the values defined as suitable for solid waste disposal areas. In the permeability tests, the points analyzed in both the study area and the control point presented values higher than the value of 10-8 m/s recommended in NBR 13896. Regarding saturated hydraulic conductivity, there were differences in values compared to the permeability tests in the field, which may occur because the laboratory test was unable to fully reproduce the flow dynamics in the soil.