Tschudi Copper Mine

Tschudi Copper Mine: Origins

Construction of the Tsumeb smelter during the 1960’s provided impetus for regional exploration to accelerate in an effort to diversify the plant’s sources of ore feed. Tschudi was first subject to exploration drilling in the 1970’s. Development initially took place as a small underground operation from 1980, but remained limited by capacity and financial constraints of the Tsumeb smelter which was subject to common ownership.

Divestment of the Tsumeb smelter in 2010 by Tschudi’s former parent company – Weatherly International Plc – provided a catalyst for development of the modern Tschudi open pit, processing and supporting infrastructure. The Weatherly mine plan targeted shallow oxide ores with processing via on site heap leach.
At a capital cost exceeding US$80million, construction of the modern Tschudi mine took place between 2013-14 providing state of the art infrastructure, including:

• Power line, substations, and power supply;
• Borefield and pipelines for water supply;
• Access roads from Highway;
• Security Fencing and Gates;
• Workshops and Offices for the mine and plant;
• Heap Leach Pads and Waste Storage Facilities;
• Solvent Extraction/Electro Winning (SX/EW) plant

The processing facilities developed at Tschudi allowed production of pure refined copper on site for the first time on a commercial scale in Namibia. Production of LME Grade A copper cathode commenced in 2015 and continued at a rate of around 15ktpa until 2020. Whilst in operation, Tschudi provided its host community with abundant employment opportunities, such that 98 percent of its 850 person workforce were Namibian citizens. The mine also commanded an excellent safety record, achieving over 1110 days and 6million hours worked free of LTA incidents.

Its historical financial performance under Weatherly’s management was impacted by lower than expected metallurgical recoveries throughout the life of mine, and a flooding event during 2018 which culminated in its former parent company being placed into administration.

Members of the CCC team were subsequently appointed by Tschudi’s administrators to responsibly manage the mine, overseeing its Care and Maintenance from 2020 whilst developing a sustainable long term restart plan.

Proactively Mitigating Historical Risk Factors

A foundation of CCC’s restart planning for Tschudi was to comprehensively study and understand risk factors that impacted its historical financial performance, and develop bankable mitigation strategies to support future production.

Initial due diligence undertaken by the CCC team at its inception did not identify any ‘red flags’ that could impede development of a sustainable long life restart at Tschudi. Several risk factors requiring mitigation were identified and the major ones included water management and metallurgy.

Lower than forecast metallurgical recoveries remained an issue throughout Weatherly’s mining campaign at Tschudi. Compared to a forecast of 85% in Weatherly’s original 2012 Feasibility Study, CCC estimates that actual recoveries were in the order of 63%. This was due to inadequate distinction and separation of ore types during the mining phase.

CCC has addressed this risk within its mine plan and processing strategy. Ore of different mineral types will be mined selectively and stockpiled separately on the Run-of-Mine (ROM) pad to ensure the processing circuit is fed appropriate ore types.

To further improve the processing recovery, CCC has undertaken extensive metallurgical test work focused on optimising recoveries from the existing heap leach plant and potential expansions of the plant to accommodate additional ore types. CCC’s restart strategy is thus initially focused on better utilising Tschudi’s existing state of the art heap leach facilities whilst accommodating future upgrades to support long term production from its deeper sulphide ores.

As the mine deepened during the Weatherly era, water management became an unexpected issue, which, in conjunction with the aforementioned recovery shortfalls, drove Weatherly’s final descent into administration.

In May 2018, scheduled blasting within the pit fractured a fault, creating an inrush of water from a previously unknown aquifer which flooded the pit and interrupted production. Subsequent upgrades to the dewatering infrastructure were reactive and capacity constrained by the mine’s power supply. Whilst water levels eventually became low and manageable after constant pumping, costs were high due to forced reliance on temporary diesel infrastructure and a lack of opportunity to understand the local hydrology.

To address this risk CCC has committed to invest in a state of the art water management network surrounding the mine which will also deliver fresh, clean water to the local community for agricultural use. CCC has undertaken hydrological studies of the local area and engaged independent engineers to design a new, modular, mobile, fit for purpose solution that will be connected to the electricity grid as opposed to the historical diesel powered network.

The modular design enables capacity to be switched on/off and the infrastructure to be relocated as needed. Performance of the network is expected to be significantly enhanced by its extension to local community agricultural groups. During the Weatherly era, discharge points for water removed from the pit were sub optimal as water was being recycled back into the same aquifer impacting the pit. By undertaking additional investment in the mine’s water distribution infrastructure, CCC aims to deliver a scarce natural resource to the local community, pacify a major historical risk factor, whilst enhancing the mine’s operating cost profile as it develops Tschudi’s long term restart plan.

Restart Planning Process

After overseeing a safe and successful period of Care and Maintenance at Tschudi since 2020, CCC was established by the current team to develop, finance and execute a sustainable long term restart plan for the mine.

CCC’s restart planning has focused on exploration and metallurgy to understand the scale of the deposit at Tschudi and optimal methods for processing its ores. At CCC’s point of inception, Tschudi’s existing reserves were only sufficient to support a mine life of under three years. This was due to the size of the existing mineral resource estimate as well as significant levels of unrecovered copper remaining in the ores.

The pre-existing resource estimate at Tschudi was largely based on 26km drilling undertaken in 2006-07 by its previous owner. During 2023, CCC undertook the mine’s first exploration drilling program in 15 years. This ‘phase 1’, 20km program confirmed extensions of the orebody along strike and at depth, more than doubling the mineral resource estimate at Tschudi. With the deposit remaining open along strike and depth, there remains considerable further scope to grow the Tschudi resource. By comparison, reserves at Zambia’s Kansanshi and Sentinel mines – which rank amongst the largest copper mines in Africa by capacity – are each supported by over 1000km drilling.

In parallel to demonstrating the deposit’s scale – CCC has also undertaken extensive metallurgical test work programs to identify the optimal processing method for Tschudi. These studies have confirmed that existing processing infrastructure remains in excellent condition and capable of processing the majority of ores identified to date at Tschudi.

Together, these initiatives are targeting an extension of Tschudi’s mine life from under three years at CCC’s inception to over ten years, supporting a sustainable, long life restart of the operation whilst its potential to transform into a ‘tier 1’ asset analogous to copper deposits of central Africa is evaluated.

Key Operational and Processing Facilities in Place

Supported by over $80million invested at Tschudi to date establishing the existing pit and heap leach processing facilities, CCC is targeting a restart of the mine in 2024. The Tschudi community irrigation project is a center piece of the Company’s restart plans. Surplus water from the existing pit is scheduled to start flowing to community agricultural groups, with inflows from the local Tschudi aquifer to be recycled as a source of regular supply.

During initial phases of the irrigation project, production is planned to be sourced from existing stockpiles. Dewatering of the pit is required to commence a staged cut back to facilitate access to extensions of the orebody delineated in recent drilling. This will enable production to scale up toward name plate capacity as run of mine ore is fed through the processing plant.

Access to the pit following its dewatering will also enable CCC to undertake exploration drilling focused on depth extensions of the resource. Many analogous deposits from the Central African Belt host “feeder pipes” of high grade mineralisation below disseminated near surface material such as that encountered so far at Tschudi. To date, the quantum of exploration drilling at Tschudi remains a fraction of that typically undertaken at its Central African Belt counterparts. With longevity of the neighbouring Tsumeb deposit offering inspiration, the CCC team is committed to assessing its full potential.