American Uranium Ltd (ASX:AMU, OTC:AMUIF) mobilised a mud rotary drill rig to the Lo Herma ISR uranium project in Wyoming’s Powder River Basin, with drilling due to restart in the week starting February 9, 2026, ahead of an interim Mineral Resource update targeted for March 31, 2026.
The program is aimed at expanding and upgrading Lo Herma’s current 8.57Mlb uranium resource, with the next round focused on step-out drilling north of Mine Unit 2. American Uranium expects to drill up to 15 additional holes for around 6,900 metres (about 22,500ft) as it continues resource development work following a successful 2025 campaign.
That earlier phase comprised 50 holes for approximately 15,000 metres (around 50,000ft) completed in December 2025, which the company said extended mineralised trends by 3 kilometres along strike and targeted expansion primarily north of proposed Mine Units 1 and 2. American Uranium expects those results to contribute to the end-of-Q1 2026 resource update.
Lo Herma drilling is being conducted under a permit covering up to 121 drill hole locations and up to 37,500 metres (about 123,000ft) of drilling, which American Uranium said supports multiple workstreams required to advance the project.
“Following our successful 2025 drilling program, we are pleased to restart drilling at Lo Herma with a focused program designed to further expand the resource size and geological confidence north of proposed Mine Unit 2, in advance of an interim Mineral Resource update by the end of March," AMU CEO and executive director Bruce Lane said.
“This work will also help refine the planned Q2 infill drilling campaign prior to a further Mineral Resource Estimate upgrade and an updated Scoping Study in Q3 of 2026. The Scoping Study aims to demonstrate Lo Herma’s potential to deliver similar economic potential to ISR uranium mines currently planned or constructed in Wyoming such as Ur-Energy’s Shirley Basin project.
“Our resource development drilling programs and recent successful hydrogeological study at Lo Herma represent major steps toward advancing one of America’s most promising ISR new uranium projects. Lo Herma is one of the few near-term, low-cost ISR projects in the U.S. and the drilling campaigns are targeting both growth of the current 8.57Mlb resource base and increased confidence in Mineral Resources.”
What's next
Following the current step-out program, the company is planning an infill drilling phase in Q2 2026 of around 56 holes for roughly 16,000m (about 52,000ft).
The stated objective is to upgrade Inferred material to Indicated or Measuredcategories within Mine Units 1 and 2 to lift resource confidence ahead of a further Mineral Resource upgrade and an updated Scoping Study expected in Q3 2026.