The Tumas project is the development of palaeochannel /calcrete-type uranium deposits located in Namibia.

The project comprises Tumas 1, Tumas 2, Tumas 3, Tumas 1 East and Tubas Red Sand/Calcrete orebodies.

It is owned and managed by Reptile Mineral Resources and Exploration (RMR), a fully owned subsidiary of Australia-based company Deep Yellow.

The company announced positive results from an initial Scoping Study in January 2020. A Pre-Feasibility Study (PFS) on Tumas project was completed in February 2021.

Project Gallery

Deep Yellow released the results of the Tumas Definitive Feasibility Study (DFS) in February 2023. The initial capital cost for the project is estimated to be approximately $372m.

The Final Investment Decision (FID) on the project will be made in the first half of 2024, with production expected to ramp up in fourth quarter of 2025.

The Life of Mine (LOM) of the Tumas project was estimated to be 22.25 years. However, additional resources discovered at the property increased LOM to more than 30 years.

Tumas Uranium Project Location

The Tumas Project is located in Namibia, around 80km from the coastal town of Swakopmund and 80km ENE from the Seaport of Walvis Bay.

The project can be accessed via the sealed C28 road.

Background Details

In 2005, Reptile Mineral Resources and Exploration (Proprietary) acquired Reptile Investment Four (Proprietary), which was renamed Reptile Uranium Namibia (RUN) in 2006.

RUN acquired tenure of the Tumas project under EPL3496 and 3497 in 2006.

Deep Yellow, through its wholly-owned subsidiary Deep Yellow Namibia, acquired RMR in 2008.

The mining licence (ML 237) for the Tumas project was issued by Namibia’s Ministry of Mines and Energy in December 2023. The ML 237 is valid for 20 years.

Geology and Mineralisation

Surficial uranium deposits are found primarily between the Great Escarpment in the east and the coast in the west.

According to the Tumas Project DFS, the deposits are associated with fluviatile environments within palaeovalleys of ancient rivers.

Uranium mineralisation in palaeochannel/calcrete-type deposits occur as carnotite, a uranium-vanadium mineral, in Tertiary and Quaternary fluvial sediments occupying narrow and steep-sided palaeochannels.

The project features varied types of host rocks from hard, carbonate-cemented sandstones and conglomerates to poorly consolidated and friable sands.

Tumas Uranium Reserves

Exploration activity at Tumas since 2016 led to a more than fourfold increase in the project’s palaeochannel/calcrete resources.

According to the DFS, Tumas has a resource of 200.5Mt (Indicated + Inferred) (258ppm U3O8).

It is estimated to host 88.4Mt of probable mineral reserves grading 345ppm U₃O₈ for a total of 67.3 million pounds (mlb) in contained U₃O₈.

In November 2023, Deep Yellow Limited announced an updated Mineral Resource Estimate for the Tumas 3 Deposit that increased total indicated mineral resources of Tumas MLA increased to 108.5Mlb at 265ppm eU3O8.

Uranium Mining and Processing

The uranium project will be mined via a conventional shallow open-cut truck and shovel operation. It will involve the use of conventional excavators and haul trucks.

Operations may include open cast mining using 3m high flitches, following stripping of unconsolidated sandy grits and screes.

Mining is planned to commence with the Tumas 3 southeast pits, advancing to the Tumas 3 western stages and terminating at the Tumas 1 and Tumas 1 East stages.

Initially, the project will aim to produce 4.15 Mt/y of ore feed for the plant for LOM and 3.6 Mlb/y of U3O8 product.

The processing will include beneficiation followed by leaching, solid-liquid separation, pregnant leach solution (PLS) concentration, vanadium recovery, uranium recovery, and uranium barren liquor (UBL) treatment.

The process plant tailings will be stored within the Tumas 3 pits.

Tumas Project Infrastructure

The project development will include the construction of a 13.5 km site access road and a 65km water supply pipeline.

The project will be connected to the Namibian regional grid via a new dedicated 45.1km 132 kV power line from the existing Kuiseb substation.

The power will be stepped down to 11kV at the main Tumas substation before it is transmitted to the two main switchboards in the process plant.

Deep Yellow also plans to build a 20 MW solar farm to reduce reliance on grid power and lower CO2 emissions.

The solar farm will be located to the east of the process plant in an area of approximately 45 hectares (ha).

Freshwater required for the project operations will be supplied from the Namibia Water Corporation (NamWater) managed Swakopmund Reservoir via a 2.4 GL/y 65km pipeline parallel to the C28 highway.

Key Contractors Involved

Australia-based Ausenco Services prepared the Tumas DFS Executive Summary report.

In April 2023, independent consultant and Environmental Practitioner Namisun carried out the Environmental Impact Assessment for the Tumas Project.

Cube Consulting was engaged to undertake the Tumas Ore Reserve Update.