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M.Sc. / The Merriespruit Tailings dam disaster killed seventeen (17) people and covered a part of Virginia with approximately 2.5 million cubic metres of tailings, causing such an emotional uproar that all resources were focused on repairing the dam and addressing some of the social issues. Little attention was given to the environment. The identified need in this study was therefore to investigate the consequences of the disaster on the environment, a need which derives from the uniqueness of this particular disaster and its consequences. The Department of Minerals and Energy require the submission of an Environmental Management Program Report (EMPR) on all prospecting and mining operations. It is clear that, in the compilation of such an EMPR, Harmony Gold Mine neglected to establish a Management Plan to regulate the physical impact of the disaster on the environment, mainly because no attention was given to disasters in the Aide-Memoir. A Management Plan was established by adapting existing formats of management plans to the uniqueness of this disaster. By following the procedure stipulated in the Management Plan it can be ensured that Environmental Management requirements will be effectively integrated into either the project management actions and contracts or operational systems and processes for the following issues: • Water management • Storm water control • Waste management • Dust • Aesthetics and socio-economic implications • Rehabilitation of the area. The investigation showed that the disaster exerted a definite negative influence on the environment, which can be managed by taking preventative measures stipulated in the Management Plan. However, one of the main issues identified in this study is that storm water management has been problematic for a period of time. It is therefore noted that some attention should be given to establishing a wetland system to contain the storm water runoff. Although this study does not focus on the socio-economic impacts in detail, it is recommended that these impacts are considered as it is evidently problematic. The primary aim of this study was to compile an EMP in order to manage, and possibly mitigate, the physical impact of the disaster on the immediate environment, an aim which clearly was accomplished. Harmony Gold Mine can benefit from the compilation of this EMT, as management goals were set and feasible means of achieving them were specified.

[Truncated abstract] As mineral deposits continue to be mined, the non economic gangue materials such as sulphides (e.g. pyrite) that are extracted as part of the ore body or overburden are deposited within the waste rock and/or milled tailings. As a result of natural weathering processes, these reactive materials represent a potential hazard to surrounding environments. A major consequence, resulting from mine-waste impoundments containing sulphidic materials, relates to the offsite movement of low pH leachates containing elevated concentrations of metal ions posing a contamination threat. The processes and mechanisms acting in the formation of acid mine drainage (AMD) are highly variable and, to a high extent, controlled by climatic conditions as the main driver of water flow and wetness of the system which in turn determines the availability of oxygen as well as water for pyrite weathering. In particular, this thesis is based on the hypothesis that in semiarid and arid climates the acid production may be water … The experiments were repeated at different water contents ranging from 0.24 to 0.33 cm3 cm-3. Breakthrough curves (BTC) of Li+, K+, Ca2+, Mg2+, Na+ and pH were measured and described with models of different complexities. This included the use of a simple linear and non-linear isotherms for Li+ alone, a binary Li+ - K+ ion exchange, and a complete multicomponent chemical equilibrium description of ion transport. The latter, by including dissolution of primary minerals which released base cations such as Mg2+, Ca2+ and K+ explained some of the elution patterns of base cations for which the Li+ - K+ exchange was the dominant process. Furthermore, under unsaturated water flow conditions, retardation of Li+ increased with decreasing water content. Thus solute mobility in mafic rock tailings appears to decrease under strongly unsaturated water flow conditions.