Cauldron Confirms Low Chloride and Sulphate Levels in Yanrey Groundwater

Groundwater Quality Validates ISR Potential

Cauldron Energy Limited (ASX, CXU) has taken a significant step forward in its quest to develop the Yanrey Uranium Project in Western Australia. The company announced that groundwater samples collected during its 2025 drilling campaign at key palaeochannel sites; Manyingee South, Manyingee North, and Cosgrove; exhibited low levels of chloride and sulphate. These chemical signatures are critical indicators that the groundwater is suitable for in situ recovery (ISR) uranium mining, a method prized for its low environmental footprint and cost efficiency.

The water testing was performed by the Minerals division of the Australian Nuclear Science and Technology Organisation (ANSTO), a respected authority in uranium mining technical services. This marks the first time Cauldron has obtained groundwater data from Manyingee North and South, complementing prior analyses at Bennet Well and reinforcing the project’s overall ISR viability.

Expanding Uranium Resources Across Multiple Deposits

The Yanrey Uranium Project spans approximately 1,250 square kilometres and hosts a substantial uranium resource base exceeding 42 million pounds of uranium oxide. The flagship Bennet Well deposit alone contains nearly 31 million pounds, while the recently discovered Manyingee South deposit adds over 11 million pounds. Exploration drilling in 2025 also uncovered promising mineralisation at Manyingee North and Cosgrove, with resource estimates for Manyingee North and updated figures for Manyingee South expected by mid to late February 2026.

These deposits lie within complex Early Cretaceous palaeochannels, ancient river systems that have proven to be fertile grounds for uranium mineralisation. Cauldron’s exploration strategy combines airborne electromagnetic surveys with passive seismic methods and targeted aircore drilling, enabling the company to map and test these channels effectively.

ISR, A Low-Impact, Commercially Attractive Mining Method

In situ recovery mining involves extracting uranium directly from underground sandstone aquifers by circulating a leaching solution, avoiding the need for traditional open-cut or underground mining. This technique is globally recognised for its minimal environmental disturbance and lower capital expenditure requirements. Cauldron’s CEO Jonathan Fisher highlighted that over half of the world’s uranium production now comes from ISR operations, underscoring the method’s growing importance.

Cauldron is also advancing its technical capabilities through a partnership with Navoiuyran, a leading global ISR operator. This collaboration aims to leverage Navoiuyran’s extensive experience to optimise Yanrey’s development pathway.

Looking Ahead, Drilling and Resource Updates

Building on the positive groundwater results, Cauldron plans to continue groundwater sampling alongside further aircore and diamond core drilling throughout 2026. These efforts will support updated mineral resource estimates and help refine the project’s technical and commercial parameters. The company’s methodical approach reflects a commitment to proving up a world-class ISR uranium operation in a region with significant exploration upside.

With the uranium market dynamics increasingly favouring low-impact, cost-effective production, Cauldron’s progress at Yanrey positions it well to capture emerging opportunities. The combination of robust resource potential, favourable groundwater chemistry, and strategic partnerships sets a promising stage for the company’s next phase.