Peninsula Energy has started the process to amend the license and permits for its Lance in-situ leach (ISL) uranium project in Wyoming, after laboratory tests showed that using an acidic rather than alkaline mining solution could potentially transform the project’s operating performance and costs.
Tests using mildly acidic solutions have shown greatly increased recovery, with solution grades of 295 mg per liter U3O8. This is over 10 times higher than the 22 mg per liter achieved in actual alkaline operations. Transforming to a so-called “low pH recovery system” could also position the company to respond rapidly when uranium markets improve, Peninsula said. Based on its studies, the company has concluded that the project’s performance under the current alkaline lixiviant process is unlikely to achieve the production rates and unit costs needed for sustainable long-term commercial success “at anything other than substantially increased uranium prices”, it said.
Operations commenced at Lance’s Ross Permit Area in December 2015. Perth, Western Australia-based Peninsula made its first delivery of uranium under its wholly-owned subsidiary Strata Energy Inc’s 2011 sale and purchase agreement with an unnamed US utility in January 2016. Lance produced 34,500 pounds U3O8 (13.3 tU) during the third quarter of 2017, results the company said represented consistent improvement over recent quarters but which still remain below internal target levels.
At full capacity the Lance Projects development plan comprises a three stage ramp up:
Stage 1 – production rate of between 500,000 and 700,000 lbs U3O8 per annum;
Stage 2 – production rate of up to 1,200,000 lbs U3O8 per annum; and
Stage 3 – production rate of up to 2,300,000 lbs U3O8 per annum.