At Mogalakwena Sandsloot, mechanised lateral development and a structured skills programme are carrying the Phase B extension towards trial stoping
When an open pit reaches the limits of what can be mined economically from the surface, the next tonnes often sit directly underneath it. That is the situation at Mogalakwena Sandsloot in Limpopo, South Africa, where Redpath Africa Limited is developing an underground mine beneath an existing pit. The current Phase B extension is running ahead of its development schedule, and the contractor is using the project to build a deeper pool of South African underground skills at the same time.
A decline instead of a shaft
Mogalakwena, near Mokopane in the Waterberg District, is a major platinum-group metals complex owned by Anglo American Platinum. The Sandsloot underground project is designed to reach deeper mineral resources beneath the open pit, with access developed through a decline rather than a conventional vertical shaft.
Redpath’s scope brings several specialist disciplines under one contractor: underground development, construction, raiseboring and preparation for longhole stoping. On a project of this kind, progress depends on more than metres advanced. Excavation, ground support, ventilation and underground services all have to be ready in the right sequence before the next stage can start.
Mechanised from face to haulage
Lateral development is a core Redpath capability, and at Sandsloot it is carried out with mechanised drill-and-blast methods. Development drilling rigs, trackless loading and hauling equipment, including loaders and underground haul trucks, and mechanised installation of ground support form the backbone of the operation, alongside specialised underground construction services.
The work programme has had to adapt to geological conditions and to infrastructure requirements as they evolved. That flexibility is managed through close day-to-day coordination with the mine’s technical teams, sharing operational information and aligning execution with mine planning.
“Having spent more than 20 years in contracting, this is one of the smoothest operations I have worked on. I believe that is a result of the contribution from both parties and the level of engagement between us,” says Eldie Nortier, Contracts Manager, Mining, at Redpath Africa.
He describes a relationship that goes beyond the usual contract boundaries. “We do not approach the relationship simply as a client and contractor. We see ourselves as business partners,” Nortier explains. For mine owners, that kind of joint problem-solving is often what keeps a complex underground schedule on track when ground conditions change.
Closing the skills gap
Alongside production, Redpath has placed specialist trainer-operators on site to train South African personnel in development drilling, longhole drilling, remote operation and other specialised underground tasks.
The results are measurable. Assessments during the project show a narrowing gap in average drilling performance between South African and expatriate operators, while local crews have also delivered strong overall drilling output. Redpath has additionally had its expatriate electricians accredited as competent electricians under South African requirements.
“Bringing in specialist expertise is only part of the process. We also need to develop our local workforce,” says Nortier.
For the wider industry, this matters. Highly mechanised underground mining depends on operators and technicians who can run and maintain sophisticated equipment safely, and that capability is in short supply in many mining regions.
Next milestone: trial stoping
Phase B is scheduled to run until August 2027. Recent work includes critical ventilation infrastructure and preparation for trial stoping, which will show how the chosen mining method performs under the project’s operating conditions. The outcome of those trials will set the conditions for the next phase of the underground operation.
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