Rosh Pinah Zinc (RPZ), the operator of the Rosh Pinah mine, alongside investment adviser Appian Capital Advisory, has officially commissioned Namibia’s first-ever paste backfill plant—a significant technological advance for the country’s mining sector. This achievement is a central milestone in the RP2.0 expansion project, which has now surpassed 85% completion and remains on track and within budget.
A paste backfill plant is a facility that takes processed mine waste, known as tailings, mixes it with binders and water, and creates a thick paste. This paste is then pumped back underground to fill empty mined-out areas, helping support the rock above and making underground mining safer and more efficient. By recycling tailings in this way, the plant reduces the volume of waste stored on the surface and helps minimise the mine’s environmental footprint.
The expansion also introduces a semi-autogenous grinding (SAG) mill—a large rotating machine that grinds ore into smaller pieces using both the ore itself and added steel balls. This process is vital for efficiently extracting valuable minerals by preparing the ore for further processing and boosting overall production capacity.
As part of its exploration programme, RPZ is carrying out infill, step-out, and regional exploration drilling. In simple terms, infill drilling fills in gaps in known ore areas to confirm resources, step-out drilling tests new extensions of a deposit beyond current boundaries, and regional drilling explores entirely new zones. Together, these drilling methods help identify and expand mineral resources, supporting the mine’s long-term future.
According to RPZ, the paste backfill plant is a cornerstone of the RP2.0 expansion, designed to support underground mining by safely filling mined-out voids. This technology helps reduce mining dilution, improves ore recovery, and lowers the amount of waste stored on the surface—all key for more sustainable and profitable operations.
The RP2.0 expansion is set to nearly double the mine’s annual processing throughput to 1.3 million tonnes. Construction progress has now exceeded 85%, with completion targeted for the third quarter of this year and ramp-up to follow soon thereafter. This marks the first use of paste backfill technology in Namibia, enabling safer, more efficient underground mining and a smaller surface footprint.
RPZ has also invested in training its local workforce to operate and maintain the new plant, aiming to embed valuable technical skills within Namibia and support long-term employment.
The introduction of cutting-edge mining technology like the paste backfill plant positions Namibia as a leader in mining innovation on the African continent. This leap forward is expected to attract further international investment, create new jobs, and set higher standards for operational safety and environmental sustainability across the sector. For local communities, the expansion brings economic opportunities—from direct employment and training to increased demand for local services and suppliers.
Environmental sustainability also stands to benefit. By reusing mine tailings underground and reducing the amount stored above ground, the project minimises land disturbance and helps protect local ecosystems—a priority for both the company and the Namibian government.
“Commissioning the paste fill plant represents another major step forward for RP2.0. These facilities enhance the efficiency and sustainability of our operations. With construction now more than 85% complete, we are firmly on track, on schedule and on budget to deliver the RP2.0 expansion safely and responsibly,” said RPZ General Manager Alex Mayrick.
Appian Capital Advisory, the investment adviser to RPZ’s owners, added that the milestone “demonstrated continued progress in executing the expansion strategy.” Ignacio Bustamante, Appian’s head of base metals, noted: “The commissioning of the paste fill plant demonstrates RPZ’s ability to execute on key milestones and deliver modern, sustainable infrastructure. This achievement further strengthens RPZ’s operational foundation as we approach the final phases of construction.”
Local government officials have praised the project’s focus on skills transfer and sustainable practices. “Rosh Pinah’s investment in workforce development and environmental management sets a benchmark for other operations in the region,” commented a representative from the //Karas Regional Council. Community leaders have likewise welcomed the expansion, highlighting increased employment opportunities and the positive impact on local businesses.
In parallel with construction, RPZ’s extensive diamond drilling programme—planned to cover over 80 km through 2027—continues to return encouraging results, indicating the potential for further resource growth. As Mayrick said, “our exploration programme is delivering encouraging results, reinforcing the strong growth potential of RPZ as we continue to build a larger, longer-life operation.”
With its array of innovative technologies, local investments, and sustainability initiatives, the Rosh Pinah RP2.0 expansion is poised to strengthen Namibia’s reputation as a mining leader and deliver lasting benefits for its people and environment.