American Uranium Ltd (ASX:AMU) is preparing to advance its Lo Herma In-Situ Recovery (ISR) Uranium Project in Wyoming’s Southern Powder River Basin with hydrogeologic testing and a major resource expansion drilling program scheduled to begin in the fourth quarter of 2025.
The testing and drilling initiatives are designed to underpin an updated Mineral Resource Estimate (MRE) in the first quarter of 2026, followed by a revised Scoping Study later in the year.
Hydrogeologic testing of monitor wells will confirm Lo Herma’s aquifer conditions to ensure efficient ISR mining methods.
Step-drawdown pumping tests will be conducted to evaluate sustainable pumping rates and optimise wellfield planning.
Longer-term testing with additional monitor wells will provide data to support future permitting requirements.
Alongside this, American Uranium will commence an extensive resource development drilling program, with federal and state approvals already in place.
The program will include step-out drilling north of proposed Mine Units 1 and 2 to target resource growth, while infill drilling will seek to upgrade Inferred Resources into higher-confidence categories.
American Uranium CEO and Executive Director Bruce Lane said the dual initiatives mark a key milestone for Lo Herma.
Lane said the forthcoming drilling and hydrogeology programs at Lo Herma mark a significant step in progressing what he described as one of the country’s most promising ISR uranium projects.
He noted the work will aim to expand the resource base, improve confidence in existing resources, and provide further confirmation of the project’s hydrogeology.
“The program is targeting an increase of the current 8.57Mlbs (32% indicated) eU3O8 Mineral Resource Estimate by converting Exploration Target Range mineralisation for Lo Herma, which currently stands at 5.6 to 7.1 million tonnes at a grade range of 500 ppm to 700 ppm eU3O8.
“This work is expected to feed into an updated Mineral Resource Estimate and Scoping Study in 2026, positioning us to deliver value from America’s nuclear energy revival.”
Lo Herma currently hosts an MRE of 8.57 million pounds eU3O8, with 32 per cent in the Indicated category.
The forthcoming drilling and testing programs aim to expand these figures by converting the Exploration Target mineralisation and demonstrating robust aquifer conditions for cost-efficient ISR recovery.
By combining hydrogeologic validation with targeted drilling, American Uranium expects to strengthen Lo Herma’s standing as one of the United States’ most advanced and strategically positioned domestic uranium projects.
