Ardea Resources Updates Goongarrie Hub DFS Timeline to H1 2026

• Definitive Feasibility Study completion now scheduled for first half 2026, delayed from December 2025 due to cumulative delays across work streams
• Japanese Consortium earned 17.5% stake in KNPL after contributing $49.25 million towards DFS expenditure
• Heritage Agreement executed covering approximately 75% of Goongarrie Hub mineral resources
• Technical team visited SMM's Taganito HPAL facility in Philippines for knowledge sharing
• Zero lost time or recordable injuries maintained through August 2025

Ardea Resources (ASX:ARL) is developing the Kalgoorlie Nickel Project through a joint venture with Sumitomo Metal Mining and Mitsubishi Corporation. The company holds Australia's largest nickel-cobalt resource at 854 million tonnes containing 6.1 million tonnes of nickel and 386,000 tonnes of cobalt.

The Goongarrie Hub, a subset of the Kalgoorlie Nickel Project, contains 584 million tonnes for 4.0 million tonnes of contained nickel. The project is managed by joint venture company KNPL, with the Japanese Consortium funding the $98.5 million DFS through to a 50% holding at final investment decision.

DFS Schedule Revision and Project Delays

The Definitive Feasibility Study completion has been pushed back to the first half of 2026 from the original December 2025 schedule. The delay results from cumulative minor delays across several work streams rather than any single major issue.

KNPL is working to prioritise critical path activities and minimise schedule delays whilst maintaining study quality standards. The company stated that ongoing test work and design engineering have identified potential opportunities to optimise process operating parameters, though no implementation decisions have been made.

Managing Director Andrew Penkethman noted:

"Whilst any delay is disappointing, the Company notes that ongoing test work and design engineering have highlighted potential opportunities to optimise process operating parameters further."

Technical Progress and Design Advancement

Field work supporting DFS completion is largely finished, with drilling programmes completed in June 2025. The total drilling stands at 727 reverse circulation holes totalling 45,735 metres and 32 diamond holes totalling 2,277 metres, with 82% of geology results returned by July 2025.

Ausenco completed the 60% design review of the process plant with the three-dimensional model finalised. Lycopodium delivered the three-dimensional model for the H₂S plant along with the constructability and modularisation report. A 50% design review was completed for non-process infrastructure.

KNPL and Ardea technical staff visited SMM's Taganito operations in August 2025. The visit focused on design and operations of nickel laterite HPAL processing facilities and applying learnings to the project design. Capital and operating cost assessments are scheduled for completion in the fourth quarter of 2025.

Resource Model Updates and Heritage Agreements

Domain interpretations have been completed for Big Four, Scotia Dam and Highway deposits, with results provided to SRK consulting. Work on Goongarrie South and Goongarrie Hill interpretations is progressing, whilst Siberia North interpretation preparations have commenced. These updates will inform mineral resource and mine block model work.

A Heritage Agreement was executed with the Marlinyu Ghoorlie Native Title Claimant Group covering approximately 75% of the Goongarrie Hub nickel-cobalt mineral resources. The agreement excludes only the Highway and Goongarrie Hill deposits from coverage.

Test pumping of the first project borefield has been completed with aquifer modelling underway. Work is assessing the integration of mine dewatering into the site water balance, which could reduce demand on planned borefields. Additional baseline survey fieldwork has been scheduled for spring 2025.

Next Steps

Capital and operating cost assessments are due for completion in the fourth quarter of 2025. Heritage clearance is required for the next borefield testing programme planned for the fourth quarter of 2025. Additional environmental baseline surveys will be conducted in spring 2025 to cover refined project areas, with the DFS targeted for completion in the first half of 2026.

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