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Lastly, the collection of monitoring data during the tenure of the mining operation will yield an enhanced understanding of the geological, hydrogeological, geotechnical, and geochemical elements of the operation. This will be utilised to demonstrate performance against closure criteria forming the basis for future reductions in liability.
Encyclopedia Britannica, 2023
Figure 3: Kimberly Mine Museum.
Further documentation highlights the value and impact of integrating mine closure into the planning of open pit operations. For example, Sishen Iron Ore mine, with a current asset life until 2033, identified waste rock deposition as a major factor in closure liability 5. By implementing in-pit dumping following the adoption of the outer shell method for waste rock disposal, haul distances were reduced, significantly improving rehabilitation efforts. Over three years, 200 hectares were rehabilitated, compared to just 50 hectares in the first 60 years of operation. Additionally, an 80 % increase in in-pit dumping lowered operational costs by reducing haul distances, emissions and fleet requirements, resulting in total savings of approximately USD500-million 5.
Progressive mine closure, a possible solution for SA open pit mines? This section introduces an innovative concept that has emerged in the context of open pit mine closure. The term originated from the concept of Progressive Rehabilitation 1 and has since been refined.
Blackman et al.,( 2009) discussed the effectiveness of the application of a spatially managed closure planning system that allows proponents to track and measure closure progress via a web-based platform. The system was used at the Magellan mine in Western Australia. Dedicated closure tasks were established within the system and the proponent was able to allocate resources against those tasks, through standard GIS information, aerial photography and integrated documentation.
Anglo American, as stated by Grant & Botha( 2018) developed an“ Integrated Closure Planning System”. This involves a fundamental approach wherein environmental safeguarding is a priority from the onset and is sustained throughout the operational lifecycle of the mine. 5 Issues such as soil erosion, water contamination, and acid metalliferous drainage are addressed at an early stage. 4 This alignment leads to another advantage as stated by Blackman et al.,( 2009) 2; Grant & Botha( 2018) 5 in the form of a notable reduction in liability and financial burden. The financial advantage extends further, demonstrating a savvy fiscal approach that entails shielding the company from tax liabilities whilst maximising operational value. Moreover, the concept contributes to improved community relations and boosts the social licence to operate. The company demonstrates a genuine commitment to environmental preservation and post-operation wellbeing.
On the other hand, the initial costs of implementing this approach stand out as the primary disadvantage. The financial aspect often deters certain operations from adopting the system, leading to potential negative impacts on short term profits. The prospect of allocating additional resources and workforce to drive this system can raise valid financial concerns. The inherent uncertainty associated with mining operations adds complexity to crafting accurate longterm closure plans. 6 The implementation of closure activities during ongoing operations can result in operational slowdowns if not managed properly.
Methodology The study attempted to adopt international best practices for open pit mine closure within the South African context. Various online sources were utilised which include Google Scholar, Elsevier Science and Engineering Journals, Research Gate, Google Search Engine, and TD Journals. As a result, a majority of the ideas are from primary sources of information.
Keywords used in the search engines were,“ open pit mine closure”,“ mine closure optimisation”,“ South Africa mine closure’,“ community engagement in mine closure”, and“ post-land mining reclamation”. These terms were shuffled around with the aim of generating various search queries. Figure 4 represents the author’ s process in selecting material.
Key findings Ideas and concepts that are bound to have an impact on the mine closure process from the study are mentioned in this section. Site specification: Comprehending the site effectively places closure planners in an advantageous position to determine an appropriate post-mining land use. A practical element is understanding the geotechnical landscape of the site. This becomes a reality check of the possible closure options and post-closure pit slope scenarios. 3
An 80 % increase in in-pit dumping lowered operational costs by reducing haul distances, emissions and fleet requirements, resulting in total savings of approximately USD500-million. www. africanmining. co. za African Mining Publication African Mining African Mining • January 2026 • 25