Nevondo, Vhodawo2025-08-212025-08-212018-09-01https://hdl.handle.net/20.500.14519/1956Submitted in partial fulfilment of the requirements for the degree, Magister Technologiae: Environmental Management in the Department of Environmental, Water and Earth Sciences Faculty of Science at the Tshwane University of Technology.Mercury has been used for many centuries in the production of consumer products such as thermometers, electrical switches, fluorescent light bulbs, batteries, biocides and pesticides, cosmetics, and dental amalgam fillings, among others. After use, these mercury-containing consumer products form part of municipal solid waste (MSW). As a result of un-separated solid waste collection system, mercury-containing wastes tend to end up in landfills where mercury and other pollutants can leach out of products into landfill leachates. Therefore, the aim of the present study was to determine the total mercury (THg) concentrations in leachate and sediment samples collected from four selected landfill sites (three in Gauteng Province - Soshanguve, Hatherley, Onderstepoort, and one in Limpopo Province - Thohoyandou). Groundwater samples were collected from the monitoring boreholes at the four selected landfill sites during summer and winter periods The acid digestion method was employed for sample preparation, and this was followed by analysis using cold vapour atomic absorption spectrophotometry (CVAAS). The concentration of total mercury in Thohoyandou leachate, sediment and groundwater samples ranged from 0.12±0.002 - 2.07±0.28 μg/L, 0.03±0.001 - 0.48±0.002 μg/g and 0.09±0.001 - 2.12±0.28 μg/L, respectively, and in Soshanguve the concentration ranged from 0.10±0.01 - 1.20±0.27 μg/L, 0.04 ±0.01 to 0.62±0.61 μg/g and ND to 1.66±1.18 μg/L, in Hatherley from 0.42±0.01 - 1.31±0.51 μg/L and 0.06±0.02 - 0.78±0.53 μg/g for leachate and sediment, respectively (groundwater samples were not accessible at Hatherley site), and in Onderstepoort from 0.12±0.01 - 2.41±0.35 μg/L, 0.03±0.001 - 0.50±0.18 μg/g, and 0.05±0.001 to 2.44±0.47, respectively. The mean concentration ranges of total mercury in leachate, sediment and groundwater samples in winter were 1.20±0.27 to 2.41±0.35 μg/L, 0.48±0.002 - 0.78±0.53 μg/g and 1.66±0.18 - 2.44±0.47 μg/L, respectively, and in summer the concentration ranges were 0.10± 0.01 - 0.42±0.001 μg/L, 0.03±0.001 - 0.06±0.02 μg/g and ND to 0.09±0.001 μg/L, respectively. The determination of cations and anions was conducted along with the determination of total mercury. Moderate positive and strong positive correlations were observed between mercury and selected cations in leachate, sediment and groundwater samples from Thohoyandou, Soshanguve, Hatherley and Onderstepoort landfill sites during summer and winter. From the established relationship between mercury and cations, it was suggested that cations are likely to influence the behaviour of mercury and its mobilisation from leachate and sediment into groundwater. Furthermore, anions were also found to form strong complexes with mercury in leachate and sediment and thereby facilitating its mobility into groundwater. The findings of this study suggest that there is a strong likelihood of groundwater contamination by mercury from landfill leachate seepage, particularly for landfills that are not lined with geomembrane material.1-120 PagesenCC0 1.0 Universalhttp://creativecommons.org/publicdomain/zero/1.0/MercuryLandfillGautengLimpopoSouth AfricaThesis