Denison Mines (TSX: DML; NYSE: DNN) announced on Tuesday the successful completion of an independent preliminary economic assessment (PEA) for the Waterbury Lake Property in Saskatchewan, with an indicative timeline of pre-production activities beginning in 2025 and first production estimated in 2028.
The PEA evaluated the potential use of in-situ recovery (“ISR”) mining at the Tthe Heldeth Túé (formerly named J Zone) deposit, with associated processing at Denison’s 22.5% owned McClean Lake mill.
The THT ISR operation is estimated to produce 9.7-million lb. U3O8 over a six-year mine-life, with final processing occurring at the McClean Lake mill. The project has an average cash operating cost of $12.23 per lb. and an all-in sustaining costs of $24.93 per pound. Initial capital costs are estimated at US$112 million.
The company announced last week that it was ready to resume the formal environmental assessment (EA) process for the Wheeler River project, which is poised to be Canada’s first in-situ recovery uranium mine.
Denison paused the process in March, due to restrictions related to Covid-19.
“The Waterbury PEA further demonstrates the potential for the ISR mining method to change Canada’s global competitiveness in the uranium mining sector – without requiring the discovery and development of massive-scale uranium mines,” Denison president and chief executive David Cates said in a statement.
“The selection of the ISR mining method for the Tthe Heldeth Túé deposit has transformed our expectations for the project – generating robust preliminary financial results with comparatively modest upfront capital costs.”
Denison’s plan for the project includes a ‘freeze wall’ design adapted from the ‘freeze dome’ outlined for the Phoenix deposit in the Wheeler River prefeasibility study.
“The freeze wall design allows for the containment of a smaller area and a significant reduction in up front capital costs, as compared to the ‘freeze dome’.” said David Bronkhorst, vice president operations of Denison.
— This article first appeared in MINING.com, part of Glacier Resource Innovation Group.