Boss Energy has withdrawn its 2021 enhanced feasibility study (EFS) for the Honeymoon uranium project in South Australia, after a review found it no longer reflects current conditions.
The findings indicate production and cost forecasts from the 2026-27 financial year (FY27) onwards may not be reliable. The Honeymoon review revealed weaker continuity of higher-grade mineralisation, non-overlapping zones, lower leachability and smaller wellfields than previously modelled.
Boss said the EFS should no longer be relied upon as a guide to future operational performance. In response, the company has launched a new feasibility study exploring a wide-spaced wellfield design.
Still at a conceptual stage, it could lower operating costs and improve lixiviant grades by extending leaching time and using infrastructure across a larger area. Initial updates are expected in the first quarter of 2026, with a scoping study in the second quarter of 2026 and a final study by the third quarter of the calendar year.
“Work undertaken on the Honeymoon review has provided Boss with an updated understanding to indicate that execution of the wellfield design as set out in the EFS would be expected to result in a material and significant deviation from the EFS from FY27 in terms of life of mine production and cost,” Boss Energy managing director Matthew Dusci said.
“Although Boss acknowledges this disappointing outcome, the Honeymoon Review and delineation drilling programs have enabled the identification of a potential pathway forward through a new wide-spaced wellfield design.
“While additional work is necessary to finalise a new feasibility study, this development presents an opportunity for Boss to potentially lower operating costs, optimise production profiles, and extend mine life compared to the current wellfield design.”
Boss is also advancing Gould’s Dam and Jason’s Deposit satellite deposits and remains financially strong with $212 million in cash and liquid assets, able to self-fund the new study.
“If successful at Honeymoon, this style of wellfield design would be used, and could potentially improve resource recoverability and cost structure at the Gould’s Dam and Jason’s Deposit satellite deposits,” Dusci said.
FY26 guidance of 1.6 Mlb uranium oxide (U₃O₈) at $40–45 per pound (/lb) C1 cost and AISC of $75–80/lb remains on track, with 357,000 pounds already drummed to December 10, 2025.
Subscribe to Australian Mining and receive the latest news on product announcements, industry developments, commodities and more.