The new facility forms part of Nkomati Nickel Mine’s environmental preparations ahead of the planned resumption of open-pit mining in October 2026. African Rainbow Minerals is investing R753 million, approximately US$46 million, in the restart.
Nkomati Nickel Mine has officially opened a new water-treatment plant as African Rainbow Minerals advances preparations to return the Mpumalanga operation to production after five years on care and maintenance.
The facility is intended to strengthen water management and protect surrounding natural resources as mining and processing activities resume. Nkomati has not yet publicly disclosed the plant’s treatment capacity, project cost, treatment technology or water-reuse targets.
Its opening nevertheless represents an important environmental milestone within the wider restart programme. ARM has approved an investment of R753 million, approximately US$46 million, to refurbish the operation and restart open-pit mining.
Plant refurbishment began in July 2026, while mining operations are expected to resume in October.
Water management is an operational requirement
The new facility should not be viewed only as a corporate environmental initiative. Water management has previously represented a material financial and rehabilitation responsibility at Nkomati.
In its results for the financial year ended June 2024, ARM reported that an increase in Nkomati’s estimated rehabilitation costs was mainly attributable to short- and medium-term water-management requirements.
This makes the new treatment plant relevant to both environmental compliance and the operational readiness of the mine.
Mines placed on care and maintenance must continue managing water entering pits, underground workings, waste facilities and processing areas. Depending on its quality, collected water may require treatment before it can be reused or discharged.
As activity increases, Nkomati will need to demonstrate that its water infrastructure can handle the requirements of renewed mining and processing without transferring unacceptable risks to surrounding water resources.
The significance of the new plant will ultimately depend on measurable information, including its treatment capacity, the quality of water entering and leaving the facility and the proportion of treated water that can be returned to the operation.
ARM moves Nkomati back towards production
Nkomati stopped mining and production activities in March 2021 following persistent financial losses associated with operating costs and weak nickel prices.
The mine was previously owned equally by ARM and Russia’s Nornickel. In July 2025, ARM completed the acquisition of Nornickel’s 50% interest, making Nkomati a wholly owned ARM operation.
Full ownership gave ARM greater control over the future of the asset. After completing a definitive feasibility study, the company approved the restart of open-pit mining and nickel-concentrate production.
At steady state, Nkomati is expected to produce approximately 56,065 tonnes of nickel concentrate annually. This figure refers to the total mass of concentrate and should not be interpreted as 56,065 tonnes of contained nickel metal.
The operation also produces mineral products containing copper, cobalt and platinum-group metals, alongside its nickel output.
Nkomati has historically been described as South Africa’s only primary nickel operation, giving its return a wider strategic significance for the country’s base-metals industry.
Boliden agreement supports the restart
The restart is supported by a conditional nickel-concentrate offtake agreement between ARM and Swedish metals producer Boliden.
The agreement provides a potential market for Nkomati’s concentrate within Boliden’s European processing network. It also connects the restart to European efforts to diversify supplies of responsibly sourced nickel and other industrial metals.
ARM has said Boliden completed its responsible-sourcing due diligence at Nkomati. However, the restart and offtake arrangement remain subject to the fulfilment or waiver of outstanding conditions.
This distinction is important. The offtake provides commercial support for the project, but the agreement should not be described as unconditional until ARM confirms that all remaining requirements have been satisfied.
Environmental infrastructure becomes part of project economics
The opening of the water-treatment plant highlights how the economics of restarting a mine extend beyond mining fleets and concentrator equipment.
After several years of inactivity, an operator must address water management, rehabilitation obligations, environmental authorisations, worker safety, community relationships and the condition of existing infrastructure.
These requirements can influence the capital needed for a restart, the time required to return to production and the ability to satisfy customers’ responsible-sourcing standards.
For Nkomati, the water-treatment plant provides visible evidence that environmental infrastructure is being incorporated into the restart programme. It does not yet provide enough information to assess the facility’s performance or determine whether it resolves all of the mine’s water-management liabilities.
ARM and Nkomati will need to disclose the plant’s capacity, treatment process, discharge or reuse standards and monitoring results if stakeholders are to evaluate its effectiveness.
With open-pit mining targeted for October 2026, the next tests will be whether refurbishment remains on schedule, the outstanding offtake conditions are fulfilled and the mine can return to production while meeting its environmental commitments.
Key facts
- Restart investment: R753 million, approximately US$46 million
- Ownership: 100% African Rainbow Minerals
- Care and maintenance: Since March 2021
- Plant refurbishment: Commenced in July 2026
- Expected mining restart: October 2026
- Target production: Approximately 56,065 tonnes of nickel concentrate annually
- Offtake partner: Boliden Commercial AB
- Water-treatment capacity: Not yet publicly disclosed
