Journal of the Southern African Institute of Mining and Metallurgy
On-line version ISSN 2411-9717
COGHO, V.E.. Optimum Coal Mine: striving towards a 'zero effluent' mine. J. S. Afr. Inst. Min. Metall. [online]. 2012, vol.112, n.2, pp. 119-126. ISSN 2411-9717.
Optimum Coal Mine comprises numerous defunct, active, and future mining sections. The mine is primarily a large opencast coal mine; however, underground mining activities will be increasing steadily over the next five years. Opencast and underground mining activities have a significant impact on surface and groundwater resources. To ensure that the mine will be able to continue with its mining operations in the catchment, the extent of this impact requires that substantial intervention and mitigation measures need to be implemented to ensure the environmental integrity and economic use of the catchment's water resources. In developing a sustainable long-term mine water management strategy, numerous scenarios had to be analysed. The various scenarios are a combination of water and land management activities. The main components of the mine's integrated water management strategy include: Management of water recharge by continual and appropriate rehabilitation of disturbed land Beneficial re-use of impacted mine water for coal plant process water and mining operations Reclamation and desalination of remaining excess impacted mine water to potable standard. From the mine's long-term water balance, it is evident that the continued implementation of numerous water management actions is required to mitigate the water resources impact in a sustainable manner. In addition, the installation of a water reclamation plant at Optimum Coal Mine (15Mℓ/day) is a key step for the mine to achieve a zero impact target.
Keywords : opencast mining; water management; water balance; water treatment; desalination; zero effluent.