American Uranium Ltd (ASX:AMU, OTC:GTRIF) has mobilised a mud rotary drill rig ahead of schedule to begin resource-development drilling at the Lo Herma in-situ recovery (ISR) uranium project in Wyoming’s Powder River Basin. The program targets expansion and upgrading of the existing 8.57 million pounds uranium resource.
Drilling starts this week under a two-phase work plan.
Phase one focuses on resource growth to support an interim Mineral Resource Estimate (MRE) in early 2026. It will comprise about 50 holes totalling about 15,000 metres (50,000 feet), with step-out drilling to grow the resource by testing known mineralised roll-fronts chiefly north of the proposed Mine Unit 1 (MU1) and Mine Unit 2 (MU2).
“We are very pleased to be commencing Phase 1 of the resource development drilling campaign at Lo Herma ahead of schedule. We’re excited to be in a strong position to be able to complete this first phase of resource expansion drilling this quarter, with an interim mineral resource estimate update expected in early 2026,” AMU CEO and executive director Bruce Lane said.
Phase two, slated for the first quarter of 2026, will infill priority areas to increase confidence and upgrade Mineral Resource categories ahead of an updated Scoping Study expected in the second quarter of 2026.
Phase two will comprise about 71 holes totalling about 22,500 metres (73,000 feet), scheduled for early 2026, to lift resource confidence by increasing the proportion of Indicated and Measured categories within MU1 and MU2 from the current 32%.
Lo herma resource areas, proposed mine units and approximate location of planned resource development drill holes.
Immediate start-up
All key permits, bonds and site access have been secured, enabling immediate start-up. The current drilling permit allows for up to 121 holes and 37,500 metres across the proposed Mine Units 1 and 2, with activity designed to deliver both resource additions and classification upgrades.
“This program marks an important step towards advancing one of America’s most promising near-term, low-cost ISR uranium projects. Lo Herma is one of the few near-term, low-cost ISR projects in the US, and the drilling campaign will target both growth in the current 8.57Mlb resource base and increased confidence in Mineral Resources,” Lane said.
“This work is expected to feed into a further resource upgrade and updated Scoping Study in the first half of 2026 to demonstrate Lo Herma’s potential to deliver similar economic potential to ISR uranium mines currently being planned or constructed in Wyoming such as Ur-Energy’s Shirley Basin project.”
With regulatory settings in place and the rig on site, American Uranium is moving to accelerate Lo Herma’s development trajectory, positioning the project for a staged set of resource and study milestones through 2026.