American Uranium Completes Aquifer Testing at Lo Herma Ahead of Q4 Scoping Study
Key Takeaways
- Large-scale aquifer testing at Lo Herma Mine Unit 1 is now complete, with hydrogeological data under independent evaluation by Petrotek Corporation and a final report expected within weeks.
- Petrotek's findings will feed directly into the targeted Q4 2026 Scoping Study and define wellfield design parameters for Mine Unit 1, the planned initial development stage of the three-unit project.
- Total Lo Herma resources stand at 9.96Mlbs U3O8 following the 4 August 2026 JORC 2012 update, with 4.79Mlbs classified as Indicated — the higher-confidence category that underpins development studies.
- Within the Scoping Study footprint covering Mine Units 1, 2 and 3, resources increased to 7.38Mlbs U3O8 with 54% classified as Indicated, strengthening the technical foundation for the upcoming economic assessment.
- Lo Herma sits in Wyoming's Powder River Basin, a Tier-1 ISR uranium jurisdiction with established permitting pathways through the Wyoming Department of Environmental Quality.
American Uranium has completed large-scale aquifer testing at proposed Mine Unit 1 of its Lo Herma ISR Uranium Project in Wyoming’s Powder River Basin. The hydrogeological data is now under independent evaluation by Petrotek Corporation, with a final report expected in coming weeks. Results will feed directly into the targeted Q4 2026 Scoping Study and ongoing permitting activities, marking a de-risking step for the flagship 9.96Mlbs U3O8 project as it advances toward development.
A key development milestone in Lo Herma’s path forward
The completed pumping test evaluates hydrogeological characteristics relevant to ISR development at Mine Unit 1. The program was designed in consultation with Petrotek, following the sequence below:
- Large-scale aquifer testing completed at Mine Unit 1
- Hydrogeological data now under independent evaluation by Petrotek
- Final report expected in coming weeks
- Findings to feed the targeted Q4 2026 Scoping Study and permitting
The results will inform wellfield design parameters and define the next stages of hydrogeological work for aquifer permitting, both critical inputs for advancing the project through development studies.
Bruce Lane, CEO & Executive Director
“Completion of the aquifer testing program marks another important step in the advancement of Lo Herma. We look forward to receiving Petrotek’s final report and incorporating its findings into the targeted Q4 2026 Scoping Study and ongoing permitting activities.”
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What is ISR uranium mining and why aquifer testing matters
In-Situ Recovery (ISR) is a mining method that circulates solution through an ore-bearing aquifer to extract uranium, rather than conventional open-pit or underground mining. Hydrogeological data governs wellfield design, fluid movement through the ore zone, and permitting feasibility.
For investors, strong aquifer data de-risks the Scoping Study and supports the permitting pathway. Both are prerequisites to development. This test provides the technical foundation for Mine Unit 1’s wellfield configuration and informs regulatory approval processes with the Wyoming Department of Environmental Quality.
The data reduces execution uncertainty as Lo Herma transitions from resource definition to engineering and permitting stages.
Building on a growing resource base
The aquifer test follows American Uranium’s 4 August 2026 Mineral Resource Estimate update (JORC 2012). Total Lo Herma resources now stand at 9.96Mlbs U3O8, including 4.79Mlbs Indicated. Within the proposed Scoping Study footprint (Mine Units 1, 2 and 3), resources increased to 7.38Mlbs U3O8, with 54% classified as Indicated.
Mine Unit 1 is expected to represent the initial development stage within the three-unit Scoping Study.
| Category | Tonnes (M) | Grade (ppm U3O8) | Contained U3O8 (Mlbs) | Date |
|---|---|---|---|---|
| Lo Herma Indicated | 3.55 | 610 | 4.79 | 04/08/2026 |
| Lo Herma Inferred | 3.61 | 650 | 5.17 | 04/08/2026 |
| Great Divide Basin Inferred | 1.32 | 570 | 1.66 | 05/04/2023 |
| Total Mineral Resources | 8.48 | — | 11.62 | — |
The company also holds Exploration Targets across its Wyoming portfolio. These are conceptual in nature and it is uncertain whether further exploration will result in a JORC-compliant Mineral Resource Estimate in the defined areas.
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What comes next for American Uranium
The near-term roadmap centres on incorporating Petrotek’s final report into the Q4 2026 Scoping Study and defining next stages of hydrogeological work for aquifer permitting. This represents sequential de-risking of a flagship US uranium ISR asset in Wyoming, a Tier-1 jurisdiction with established ISR permitting pathways.
Upcoming catalysts include:
- Petrotek final report (expected coming weeks)
- Q4 2026 Scoping Study
- Ongoing aquifer permitting activities
The aquifer test data positions Lo Herma to advance through feasibility and permitting stages with stronger technical confidence in wellfield design and hydraulic characteristics. For investors tracking US uranium exposure, this milestone reduces technical uncertainty as the project transitions from resource definition to development planning.
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