Local Expertise Propels TSF-4 Tailings Dam Construction at Mimosa Mine
The TSF-4 tailings storage facility at the Mimosa platinum mine, built with local expertise alongside SRK Consulting, showcases Zimbabwean engineering capabilities. The project emphasizes local company empowerment, adheres to global tailings management standards, and introduces advanced drainage systems to address challenges posed by high talc content in tailings. Overall, the project represents a significant achievement in the region’s mining industry.
The construction of the TSF-4 tailings storage facility at the Mimosa platinum mine showcases the capabilities of Zimbabwean firms, working collaboratively with SRK Consulting. The Mimosa Mining Company, a subsidiary of Sibanye-Stillwater and Implats, contracted SRK Consulting (South Africa) for the detailed design of TSF-4, completed in May 2022. The subsequent contract, lasting until March 2024, includes civil works and the electrical infrastructure necessary for the facility’s operation. SRK partner and principal civil engineer Andrew Robertshaw emphasized the project’s complexity, describing it as a cutting-edge TSF structure measuring approximately 1 km by 1.3 km, with a significant storage capacity based on a projected rate of 466,000 tonnes per month over 20 years.
Empowering local companies was a fundamental aspect of the project, with significant contributions from Harare-based Forit Contracting and Kumba Resources Zimbabwe. Paterson & Cooke Consulting Engineers participated in the mechanical and electrical design. The TSF-4 was designed in alignment with the Global Industry Standard on Tailings Management (GISTM) and had to address specific local conditions, particularly the high talc content in the tailings, which affects material settlement rates and poses structural risks if not properly managed.
To mitigate the challenges of high talc content, SRK consultant Robert McNeil highlighted the necessity of a sophisticated drainage design. This design facilitates rapid removal of water from the tailings using an innovative drainage system positioned at the dam’s foundation, ensuring the water is directed efficiently to lower collection points. The system employs a pump station that transports water into a silt trap dam, where sedimentation occurs before the water moves to the return water dam.
The drainage system consists of a complex network of drains that ensure effective drainage of the outer shell of the TSF and enable monitoring of de-saturation efficiency at multiple locations. Internal paddocks adjacent to the TSF walls serve to settle coarser tailings, minimizing the risk of fine tailings and talc clogging the main drain. The strategic positioning of the main drains supports further elevation of the TSF to safeguard against potential failure risks.
A notable aspect of the TSF’s infrastructure is its dual penstock towers designed to support redundancy in case of maintenance or breakdowns. The design again follows Impala’s principle of duplicating critical components, ensuring uninterrupted functionality in the system. Additionally, the on-site laboratory established by Kumba Resources Zimbabwe, with guidance from SRK, plays a crucial role in quality assurance by providing timely material testing throughout the project development phases.
The labor force at the Kumba laboratory showcased considerable dedication, which Robertshaw praised for its attention to detail and effectiveness in supporting project timelines. Similarly, Forit Contracting’s proactive engagement illustrated the benefits of collaborative resource management, enhancing project efficiency during its progression. SRK’s construction specialists provided ongoing advice on scheduling and safety management, demonstrating the importance of coordinated efforts in successful project execution.
The developmental approach adopted during the construction of TSF-4 resulted in a significant sense of accomplishment among all stakeholders, highlighting the potential positive economic impact of responsible mining operations within local communities.
The construction of the TSF-4 tailings storage facility at the Mimosa platinum mine exemplifies the successful collaboration between local Zimbabwean firms and SRK Consulting to achieve a technologically advanced structure. By empowering local contractors, adhering to stringent global standards, and implementing innovative drainage designs, the project not only addresses environmental challenges but also enhances local economic development. This project serves as a model for responsible mining practices while underscoring the potential of local expertise in large-scale infrastructure development.
Original Source: africanminingmarket.com
