SOUTHERN AFRICA SUPPLIERS
Redpath Mining South Africa was recently awarded a mining development contract at Northam Platinum’ s number 3 Shaft, within its Zondereinde operations, in South Africa
works at Zondereinde mine, namely trackless and conventional development work; construction work, including the installation of underground stope box fronts; as well as the equipping of the Number 3 men and material shaft( still being executed).
In Northam’ s 2025 annual integrated report, it stated:“ Equipping of 3 shaft, designed for the conveyance for personnel and materials, together with services, including ventilation, process water, tailings slurry for backfill placement underground and electricity, is progressing.”
A‘ surface-to-underground’ design philosophy
Over the border in Botswana, Paterson & Cooke( P & C) is continuing to show its paste backfill engineering‘ stripes’.
From its origins in South Africa in 1991, the firm has grown into a specialist group in slurry transport, independent test work, tailings management, long-distance pipelines and backfill systems. It has a global reputation for designing integrated paste backfill systems from surface to underground.
Its recent work at MMG Khoemacau’ s Zone 5 operation in Botswana demonstrates the importance of independent test work and an integrated approach to design, system control and implementation for a safe and reliable paste backfill system, the company says.
The underground copper mine at Zone 5 requires paste backfill to enable full recovery. The orebody extends 3 km on strike, with three mining corridors and long paste reticulation distances on surface and underground. As mining progresses on retreat, high strength paste is required to maintain extraction ratios and stope turnaround efficiency. P & C was responsible for the design of the full system from surface paste plant to the underground reticulation and backfill management, taking the project from feasibility through to implementation. Tailings are dewatered at the Boseto concentrator, hauled to Zone 5 and fed into the paste plant. The paste plant consists of three modules, located in the middle of the orebody, with a design flow rate of 150 cu. m / h each. Positive displacement piston pumps deliver paste through DN200 piping to the mining declines with a paste backbone reticulation via borehole.
Given the long surface delivery distances, a high-pressure pumping system able to operate up to 150 bar was required. Dedicated high-pressure flush pumps provide redundancy and controlled flushing and pressurisation capacity in case of blockages. Due to the high pressure and full flow design implemented to reduce the wear on the boreholes, both steady state and transient hydraulic modelling was performed to define the safe operating window and keep pressures within acceptable limits, P & C explained.
While steady-state modelling defines baseline flows and sizing, it does not capture the time dependent behaviour of a modern paste system, according to P & C. Transient events such as pump trips, pipeline filling, blockages, rupture disc bursts and rapid valve closure can generate short pressure surges exceeding the values predicted by steady-state analysis. If not managed, these pressures can surpass design limits and damage supports, valves and piping, and more importantly put operators at risk.
“ Transient modelling captures these effects and guides mitigation measures such as pipe specification, support design, rupture disc sizing, dampener selection and safe operating protocols emphasising the importance of the‘ surface-to-underground’ design philosophy,” the company added.
For Zone 5, P & C completed the entire detailed system design from surface foundations to the stope. This included a transient analysis to define peak pressures and forces, and to inform the selection of pressure relief devices, anchor design and the underground piping layout. The analysis supports a control philosophy with permissives, interlocks, automated sequences and flushing modes to maintain safe operation. The approach reflects lessons learned from international operations where inadequate transient management caused support failures, excessive pipe movement or coupling fatigue, P & C explained.
The system design was further informed by a comprehensive binder testing program for the ultrafine tailings produced at Boseto.“ Ordinary Portland cement and blended cements incorporating various supplementary cementitious materials such as ground granulated blast-furnace slag and fly ash were evaluated for early- and long-term( up to 360 days) strength,” it said.“ The results guided the commercial binder selection and, importantly, a commercial adjudication informed by supplier-specific cement performance. This established a base case for supplier product performance comparison and improved binder consumption forecasting.”
The Zone 5 project illustrates the importance of having an integrated paste backfill system designed by a specialist such as P & C, where process design, independent test work, binder optimisation, hydraulic modelling, transient analysis and controls form a single package, the company says.
Surpassing safety standards
Komatsu says southern Africa and its neighbouring nations are setting global benchmarks in underground mining innovation and embracing technology to improve safety, productivity and sustainability.
Safety remains the cornerstone of this transformation with Komatsu saying it supports every step of the way with the products it brings to the market.
South Africa’ s mandate for Level 9 collision avoidance intervention technology has accelerated adoption across mines country-wide, as well as in neighbouring countries, and is an option on both Komatsu and Komatsu partner equipment. These systems go beyond alerts, actively intervening to slow or stop machines when operators fail to act, reducing accidents and aligning with the industry’ s‘ Zero Harm’ vision.“ This regulatory push ensures compliance and future-proofs operations against evolving safety standards which Komatsu works rigorously to surpass,” the OEM says.
Komatsu’ s South African designed and manufactured low-profile loaders, the WX05LP, WX06LP, WX08LP and WX10LP, exemplify its commitment to innovation. The platforms have been designed to deliver serviceability, maintainability and reduced mean time to repair – all critical for lowering operating costs. Komatsu explains:“ They feature interactive and user-friendly visual user interfaces for deep-level fault diagnostics, modular electrical systems available in 24 V CANBUS configurations and diesel particulate filters paired with highrated engines for emissions compliance.”
Off-the-shelf hose and pipe kits, preassembled panels, and electrical harnesses simplify maintenance and reduce costs, while Level 9 CAS compliance and adherence to SAN1589:2022 standards reinforce safety, it adds. Larger envelopes around the transmission and engine bay improve maintainability, while the CANBUS
18 International Mining | JANUARY 2026