Leachate composition of isale-ijagba and oke –diya dumpsites in sagamu and the possible environmental impact on surface and groundwater quality

Project Abstract

The study aimed to investigate the leachate composition of Isale-Ijagba and Oke-Diya dumpsites in Sagamu, Nigeria, and assess the potential environmental impact on surface and groundwater quality. Leachate samples were collected from the dumpsites and analyzed for physicochemical parameters including pH, electrical conductivity, turbidity, chemical oxygen demand (COD), biochemical oxygen demand (BOD), heavy metals, and organic pollutants. The results revealed that the leachate from both dumpsites had elevated levels of pollutants, with Isale-Ijagba leachate showing higher concentrations of heavy metals such as lead, cadmium, and chromium compared to Oke-Diya leachate. The organic pollutants detected in the leachate included volatile organic compounds and polycyclic aromatic hydrocarbons. The potential environmental impact of the leachate on surface and groundwater quality was assessed by comparing the leachate characteristics with relevant water quality standards. The results indicated that the leachate had the potential to contaminate surface water bodies and groundwater sources in the vicinity of the dumpsites. The elevated levels of heavy metals and organic pollutants in the leachate could pose serious health risks to humans and aquatic organisms if not properly managed. Furthermore, the high COD and BOD values of the leachate indicated a high level of organic pollution, which could lead to oxygen depletion in water bodies and negatively impact aquatic ecosystems. Overall, the findings suggest that the Isale-Ijagba and Oke-Diya dumpsites in Sagamu are sources of pollution due to the composition of their leachate. Proper waste management practices and leachate treatment are essential to mitigate the environmental impact of these dumpsites on surface and groundwater quality. Implementing measures such as leachate collection systems, liner installations, and regular monitoring of leachate quality can help reduce the pollution load and protect the environment. Further research is needed to investigate the long-term effects of leachate contamination on the surrounding ecosystems and human health, as well as to develop sustainable management strategies for solid waste disposal in the study area.

Project Overview

<p> </p><div><p>When solid waste is disposed of at landfills, it undergoes a combination of physical, chemical and microbial processes. These processes help to transform the waste into various water-soluble compounds termed (leachate) and transfer the pollutants from the refuse to the percolating water, leading to contamination of surrounding groundwater and surface water. Characterisations of the leachate originating from the Isale-Ijagba and Oke-Diya dumpsites (situated in Sagamu, Ogun State, Nigeria) as well as evaluation of the pollution potential on the quality of the local aquifer were carried out.</p><p>The composite sampling method was employed and samples collected over a period of five weeks, parameters such as, Electrical conductivity (EC), pH, Total Dissolved Solid (TDS), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), NH3–N, PO4–P, SO42−, Cl−, K+, Cd, Mn, Zn, Ni, Fe and Pb were determined using standard method for water and waste water analysis. And the data gotten analysed using Microsoft excel spreadsheet.</p><p>Mean concentration values for TDS, BOD, COD, NH4+, PO4+, SO4+ and Cl- are 493 and 534 mg/L; 1.50 and 1.08mg/L; 0.28 and 0.60 mg/L; 0.46 and 0.28 mg/L; 0.46 and 0.72 mg/L; 18.46 and 25.13 mg/L for the two monitoring wells respectively. The highest observed BOD5 and COD values were 319 and 846 mg/L; 525mg/L and 1105mg/L for Isale-ijagba and Oke-Diya leachate samples respectively. The mean concentration values for Fe, Mn, Zn, Pb, Ni and Cr- in groundwater samples are 2.81 and 1.39mg/L; 0.02 and 0.08mg/L; 0.22 and 0.21mg/L ; 0.61 and 0.61mg/L; 0.17 and 0.14mg/L and 0.11 and 0.09mg/L for Isale-Ijagba and Oke-Diya monitoring wells respectively.</p><p>The mean concentrations of all measured parameters except, Pb, Fe and Cr conform to the stipulated World Health Organization potable water standard and the Nigerian Standard for Drinking Water Quality. It was however observed that in the absence of a properly engineered landfill system, percolation of leachates into waterbodies could be deleterious in the very near future. The study recommends an upgrade of both landfill so as to guarantee adequate protection of both the surface and the groundwater resources in the locality.</p><p></p></div><h3></h3><br> <br><p></p>