Strata Energy, Inc. today announced the submission of a request to the Wyoming Department of Environmental Quality (WDEQ) to amend its Permit to Mine (PTM) to allow for the use of low-pH recovery solution in the Ross Permit Area of the Lance Projects near Oshoto.
The WDEQ PTM for the Lance Projects currently authorizes the use of alkaline and oxidant solutions in the in-situ recovery (ISR) process. These solutions are generated by mixing native groundwater with carbon dioxide and/or sodium bicarbonate and gaseous oxygen. Since uranium recovery efforts commenced in December 2015, the ore deposit at the project has proven only moderately amenable to these alkaline solutions. Despite improved production rates over the last year, the overall uranium recovery rates of the active ISR operational areas in the Ross Permit Area continue to be below targeted levels.
Strata conducted a series of bench-scale tests in late 2017, which showed a significantly increased recovery rate using low concentrations of sulfuric acid (1.5% or less). In November 2017, a White Paper was issued for public review summarizing those test results. The White Paper also examined the effectiveness of in-situ recovery of uranium using low-pH systems and summarized the history and use of low-pH ISR systems globally. The White Paper further evaluated low-pH uranium ISR within Wyoming’s regulatory program and provided recommendations for its future use at the Lance Projects. This information, together with additional data from laboratory testing and geochemical modeling conducted in 2018, was incorporated into the amendment request submitted to the WDEQ.
A successful transition to low-pH operations could align the operating performance and cost profile of the Lance Projects with current industry leading global uranium production projects. Of the 77 million pounds of uranium produced by ISR methods worldwide in 2015, ninety-six percent (96%) or 74 million pounds came from facilities using low-pH lixiviants. The proposed change to low-pH operations at the Lance Projects is also projected to require no oxidant and improve groundwater restoration. Laboratory test results and modelling indicate that groundwater can be fully restored to currently approved values after using low-pH solutions. No changes have been requested to the target restoration values previously approved for each mine unit.
Wayne Heili, Peninsula’s Managing Director and CEO commented; “The submission of the PTM amendment request is the culmination of many months of research, extensive test work and analysis aimed at greatly enhancing the uranium recovery process at Lance and marks an important milestone in the pathway to low-pH ISR operations”.
WDEQ will now undertake a comprehensive review of the amendment request, analyzing the test results and inviting public review and comment on the proposed change.