PERTH (miningweekly.com) – An enhanced definitive feasibility study (EFS) into the Tiris uranium project, in Mauritania, has increased the project’s expected average production by 150% and has increased its mine life.

ASX-listed Aura Energy on Wednesday announced that the EFS has estimated an average yearly production of two-million pounds a year of uranium oxide (U₃O₈), up from the 0.8-million pounds a year estimated in the 2021 definitive feasibility study (DFS), while the mine life has extended from 15 years to 16 years.

While the project’s post-tax net present value has increased from the $79.7-million estimated in the DFS to $226-million, and its post-tax internal rate of return from 22% to 28%, capital costs for the project have also increased from $74.8-million to $178.2-million.

Average all-in sustaining costs for the project have, however, drooped from $29.81/lb U₃O₈ to $28.77/lb U₃O₈.

“The EFS confirms the strong financial case for the Tiris uranium project. The Tiris project is unique with its low capital intensity, low operating costs, competitive all-in sustaining cost and key regulatory approvals in place. With a relatively short timeline for commercial production, the focus is now on the consideration of a final investment decision (FID) as early as the fourth quarter of 2023, which would see commissioning in late 2024 for commercial production in early 2025,” said Aura Energy MD Dave Woodall.

“What differentiates Tiris is the ore quality that allows free-dig, shallow openpit mining. Aura does not require expensive drill and blast operations or capital-hungry infrastructure for crushing and screening. Following simple scrubbing and screening the project will have a leach feed grade of >2 000 ppm U₃O₈ resulting in a downsizing of the leaching circuit that drives competitive operating costs and creates a competitive advantage for Aura Energy in a strengthening uranium market.”

Woodall said that further project optimisation will be investigated as part of the front-end engineering and design study which has commenced using the outcomes of the EFS. Additional areas of optimisation within the recovery of the U₃O₈ are under investigation and require further engineering to optimise the production profile.

In parallel with this engineering work, project financing and offtake discussions will continue ahead of a potential FID.