The high-grade rare earths Steenkampskraal Monazite Mine (SMM) is coming out of a three-year care-and-maintenance period, with the miner scheduled to conclude the reclamation and refurbishment of infrastructure on site within a year, says SMM executive chairperson Enock Mathebula.

SMM is owned by holding company Steenkampskraal Holdings and is located near Vanrhynsdorp in the Western Cape, South Africa.

“There is already a stockpile of feed-to-plant run-of-mine material available to feed the processing plant, so the construction of the new processing plant will be the primary priority on the critical path and is scheduled to commence during the second and third quarters of 2025.”

The push to restart the mine comes after approval in September by the National Nuclear Regulator (NNR) to proceed with the refurbishment of the mine’s infrastructure and reclamation of monazite material.

Steenkampskraal attained its Certificate of Registration under the National Nuclear Act (NNA), which supersedes the Mineral and Petroleum Resources Development Act and is far more onerous.

“It means that as soon as we make any operational changes on site which potentially have a radioactive exposure implication, then we have to do a full risk assessment with mitigation measures recorded, which is then submitted to the NNR for approval before we can progress with this change of scope,” stresses Mathebula.

“We are waiting on further approvals from the NNR, which will allow us to proceed with the installation of a laboratory-scale processing plant,” he adds.

Mathebula points out that the mine is not only exposed to the legislative requirements and approvals for a mining operation, but also to more stringent NNA requirements and approvals, which are underwritten by the requirements of the International Nuclear Non-Proliferation Treaty, of which South Africa is a signatory.

“We have a double whammy of legislation that we need to comply with to remain in operation,” he says.

The mine was initially placed under care and maintenance on May 7, 2021, in line with the NNA, with the aim to retain its Certificate of Registration during the period that the mine was not in production.

“The approval now allows the mine to proceed with the re-equipping of the existing headgear infrastructure and decline shaft,” says SMM CEO and mine manager Graham Soden.

He attributes the latest developments to an increased demand globally for not only injectable lead-212, which is used in cancer treatments, but also rare earth minerals such as thorium, which can be used as feedstock in molten salt reactors and is known to be a safe and reliable alternative power generation fuel.

The SMM is also considered to have some of the highest concentration of thorium globally. The abundance of natural thorium is sufficient to meet the global demand for medical isotopes from its decay for the foreseeable future.

SMM has also progressed to the final stages of negotiations with numerous offtakers targeting the rare earth elements that will be extracted, as well as thorium and radium, with radium being the parent isotope of thorium, which, in turn, is the parent isotope for injectable lead.

As the call for oncology-grade lead-212 climbs, so too does the demand for thorium-228, and, in turn, for radium-228.

The company’s plan for product offtake also involves leveraging alpha particle emitters supplier Thor Medical’s expertise to efficiently produce such valuable emitters to use in next-generation cancer treatment from feedstock originating from SMM’s mineral resources, Soden adds.

Building it Up

The refurbishment of SMM’s surface infrastructure has started, and the refurbishment of the decline shaft, headgear and underground infrastructure is planned to start during the first quarter of 2025.

“As the project now has the necessary authorisation from the NNR, the mine can move forward with the refurbishment of the current infrastructure, which requires, but is not limited to, the realignment and reinstallation of the sheave wheel on the headgear,” Soden explains.

Once this has been completed, the general upgrading of the main structure and installation of the winder rope and refurbishment of the main hoist can start.

Simultaneously, the decline shaft will be re-equipped with the power and water columns already in place, but which are not secure and require replacement and realignment.

The concrete floor of the entire decline shaft will be clad with more durable concrete, with suitably installed drainage furrows to allow for the proper washing down and recovery of potential radioactive material spillage.

This work is planned to take place during the second and third quarter of 2025 and will continue for between nine and 12 months while the processing plant will be progressed to final design and construction phases.

Plans are also underway to start construction of the first phase of the new processing plant in the second quarter of 2025, with the first production scheduled for the second quarter of 2026.

The new processing plant will use a novel technology and a proof-of-concept test phase for the generation of monazite concentrate is already underway.

The initial phases of the startup process include the removal of underground, stockpiled blasted and ballast material being stored in an underground storage bunker for later extraction to the existing feed-to-plant surface stockpile.

“Following the success of the first test, a lab-scale installation of a hydrometallurgical plant will further extend our level of plant design and efficiencies,” concludes Soden.