TSX- and NYSE-listed Denison Mines has completed the 2019 in-situ recovery (ISR) field test programme in the Phoenix uranium deposit, at the Wheeler River project, in Saskatchewan, Canada.

The company hailed the “first-of-its kind” ISR testing programme as “highly successful” and said the technical results align with expectations that the Phoenix ore zone had significant permeability and was suitable for ISR mining.

The field test programme included preliminary hydrogeological tests completed by using a series of small diameter and large diameter test wells to move water through two test areas defined within the Phoenix ore zone.

Measurements of the movement of water (hydraulic pressure changes) within the ore zone provide evidence of the hydraulic conditions present and are indicative of the potential movement of mining solution flow in an ISR mining operation.  

Additional supportive test work completed during the program included permeability and porosity tests conducted either downhole or on mineralized drill core recovered during the test program.

Denison VP for operations, David Bronkhorst, said that considerable operational milestones had been achieved during the field test programme, including the installation of the first commercial scale wells designed for ISR mining in the Athabasca basin, which were expected to meet environmental and regulatory standards.

Further, the successful testing of the MaxPERF drilling tool to increase access to existing permeability, introducds the prospect of normalising geological variations in a production environment.

“With the successful completion of the ISR field testing programme, and the recovery of significant mineralised drill core from the Phoenix ore zone, our focus has now shifted to advancing the metallurgical test work required to support our leachability reports in the PFS, and to collect additional specialized metallurgical test data to facilitate the completion of a future feasibility study,” Bronkhorst said.