Beneath Namibia’s sun-baked sands lies an invisible river — the Tumas palaeochannel. Over eons, that ancient stream carried sediments and trace uranium from distant highlands, depositing them in calcrete beds, gravels and fractures now buried under the desert.
It is this forgotten riverbed that Deep Yellow recognised and reawakened as the geological heart of the Tumas Uranium Project.
The Tumas palaeochannel, stretching more than 125 kilometres across the Namib-Naukluft National Park, has given rise to a chain of near-surface uranium deposits—Tumas 1, 2, 3, and East—each shallow and amenable to open-pit mining.
By December 2024, Deep Yellow had lifted its ore reserves to just under 80 million pounds of U₃O₈ at an average grade of about 298 parts per million, underpinning a projected mine life of 30 years at full production.
Deep Yellow owns 100 per cent of the project through its Namibian subsidiary, Reptile Uranium Namibia. A local partner, Oponona Investments (Pty) Ltd, has the right to acquire a five-per-cent interest in the project after the final investment decision.
This structure satisfies Namibia’s empowerment requirements and ensures local participation once Tumas enters production.
In September 2023, the Ministry of Mines and Energy granted the project its 20-year mining licence, ML 237, which runs until September 2043. The permit marked the transition of Tumas from an exploration venture to a fully sanctioned mining project.
According to the company’s Definitive Feasibility Study, initial capital expenditure was estimated at around US$372 million, with pre-production costs of about US$48 million.
An updated study in April 2025, after accounting for inflation and design refinements, lifted start-up capital to approximately US$474 million.
The revised model yielded a post-tax net present value of US$577 million and an internal rate of return of 19 per cent, assuming a long-term uranium price of around US$82.50 per pound. Payback is projected at six years from the start of construction, or four years from the onset of production.
Financially, Deep Yellow remains in a strong position. As of March 2025, the company held A$227 million in cash, with expectations that this would decline to between A$170 million and A$180 million by the end of the year as work progresses.
Nedbank has been appointed as the mandated lead arranger for an anticipated US$350 million debt facility to support construction once the board takes the investment decision.
Engineering and contracting work are well advanced. Ausenco was appointed as lead engineer to establish and freeze the project scope, determine the total development cost, and finalise the construction schedule.
Several early works packages, including road and site-office construction, have been completed. Contracts for power and water infrastructure are at advanced negotiation stages, and vendor selections for long-lead items such as mills and agitators have been made.
Tumas’s infrastructure blueprint includes a 13.5-kilometre access road, a 45-kilometre 132-kilovolt power line connecting to the national grid, and a 65-kilometre water pipeline capable of delivering 2.4 gigalitres annually from NamWater’s Swakopmund network. A 20-megawatt solar photovoltaic plant is also planned to supplement grid power and reduce emissions.
The Definitive Feasibility Study projects that the project will generate about 600 construction jobs, 520 direct operational jobs, and between 1,900 and 2,550 indirect and induced jobs across suppliers, logistics, and associated services.
These figures are based on Namibian mining-sector employment multipliers, which range from 3.7 to 4.9 indirect jobs per direct job.
The Tumas project was initially scheduled for a final investment decision at the end of 2024, but this was later deferred to March 2025. In April 2025, the Deep Yellow board announced that, although the project met its investment criteria, it would delay FID because uranium prices were not yet high enough to justify new greenfield development.
The company’s board approved a staged development approach, continuing detailed engineering, optimisation work, and off-site infrastructure development.
The decision to commence full-scale construction will be revisited depending on uranium market developments.
Management has indicated that, under favourable conditions, production could begin by mid-2027.
The company’s approach is to remain “FID-ready,” meaning that once uranium prices and financing conditions align, construction can start almost immediately.
Meanwhile, exploration continues to widen the project’s footprint. Between July and September 2025, Deep Yellow completed 452 reverse-circulation holes totalling 3,361 metres at the S-Bend prospect, immediately east of the mining licence. About one in three holes intersected mineralisation exceeding 100 parts per million eU₃O₈, with notable results including eight metres at 332 ppm, five metres at 407 ppm, and two metres at 1,217 ppm from surface.
The mineralisation occurs both in the overlying calcrete sediments and in fractures of the Proterozoic schists and gneisses of the Tinkas Formation. Four clusters of higher-grade mineralisation have been identified for follow-up drilling to test continuity and potential resource expansion.
If these satellite discoveries are confirmed, they could extend the Tumas Project’s already lengthy mine life and enhance its feed flexibility.
Deep Yellow sees S-Bend as evidence of the broader uranium potential within Namibia’s palaeochannel systems, a geological inheritance stretching across the Erongo Region.
When uranium markets strengthen and the final investment decision is approved, Tumas will likely become Namibia’s fifth uranium mine, following Rössing, Husab, and Langer Heinrich, with Bannerman’s Etango expected to precede it into production.
The Tumas story—rooted in an ancient riverbed and carried forward by modern engineering—captures Namibia’s evolution from desert geology to energy exporter, transforming the relics of an ancient river into a long-term source of low-carbon power for the world.
