American Uranium (ASX: AMU) Lo Herma resource growth and study timing frame ISR development pathway

American Uranium CEO Bruce Lane spoke with MarketOpen to further clarify the interim Mineral Resource update at the Lo Herma Project in Wyoming, the progression of the 121 hole drill program, and the sequencing of technical work toward a Scoping Study targeted for Q3 2026.

This Q&A focuses on the increase in contained uranium and Indicated classification, how ongoing drilling is being incorporated into the Mineral Resource Estimate, and the role of hydrogeological and metallurgical work in assessing In Situ Recovery methods. Lane also outlined how the Company is evaluating development options within Wyoming’s established ISR district as it advances toward a study level assessment.

What specifically drove the increase to 9.45Mlbs and 43% Indicated, and how much further conversion is expected from the remaining 55 holes?

The increase to 9.45Mlbs, including 43% in the Indicated category, is driven by the incorporation of additional drilling data into the updated Mineral Resource Estimate and improved classification within defined resource areas, particularly at Mine Units 1 and 2. As drilling density increases and data quality supports geological continuity, portions of the resource are upgraded from Inferred to Indicated classification. This reflects areas where spacing and confidence meet the thresholds required for higher classification under the JORC Code.

The remaining 55 holes are part of the permitted program and are expected to be completed in Q2 2026. These holes are designed to support further resource definition and expansion, and will contribute to the next resource update and Scoping Study targeted for Q3 2026. The extent of further conversion will depend on the results and their alignment with the current resource model.

How should investors assess the sequencing risk between completing drilling in Q2 2026 and delivering a Scoping Study in Q3 2026?

The drilling program and study work are being progressed concurrently with much of the study inputs already completed during the last 12 months, further results are being incorporated into ongoing technical evaluation as they become available. At the time of the interim update, 66 of 121 permitted holes have been completed, with the remaining 55 holes scheduled for Q2 2026. This next phase of the drilling will also allow the Company to  continue advancing hydrogeological and metallurgical work alongside drilling.

The Scoping Study targeted for Q3 2026 is intended to incorporate results from the remaining program together with ongoing technical work. This includes more intensive hydrogeological testing and metallurgical analysis, which will build on work done to date and are will improve the data inputs for assessing ISR development options. The sequencing reflects a structured approach where drilling and technical studies are aligned to support the planned study timeline.

What key factors will determine whether Lo Herma is developed via hub and spoke or as a standalone operation?

The development pathway will be assessed as part of the Scoping Study, which is evaluating ISR development options based on the current resource base and technical work. This includes consideration of both standalone development as a central processing plant (CPP) and satellite style development within a broader regional framework.

Key inputs include the scale and distribution of resources within Mine Units 1, 2 and 3, which form the planned study area, as well as the outcomes of the next stage of hydrogeological and metallurgical work. The project is located within Wyoming’s Powder River Basin, which hosts multiple operating and permitted ISR processing facilities, and this regional context forms part of the assessment framework for development options.

What work remains to fully validate ISR suitability across the resource, and how much of the MRE is still exposed to non ISR assumptions?

Hydrogeological testing has already been completed within portions of Mine Units 1 and 2, where results indicate aquifer behaviour and extraction rates consistent with other ISR projects in the region and are consistent with our study assumptions. However, more intensive hydrogeological data will help to further derisk the project and is planned as part of the ongoing program in Q2 2026.

ISR suitability depends on factors including permeability, transmissivity and the position of mineralisation relative to the water table. While initial testing supports ISR within defined areas, further work will improve confidence levels across the project. As outlined in the release, resources that fall outside ISR parameters may be considered for conventional mining methods, and further work is required to assess these areas.

Development pathways and execution discipline

The Lo Herma Project is advancing through continued drilling, resource updates and technical work, with a focus on Mine Units 1, 2 and 3 as the foundation for the planned Scoping Study. Ongoing hydrogeological and metallurgical programs are contributing to the data required to assess ISR development options.

American Uranium] has remaining drilling scheduled for Q2 2026 and a Scoping Study targeted for Q3 2026, the project is moving toward a defined evaluation of development pathways based on the current Mineral Resource and supporting technical inputs.

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