British Columbia-based Fission Uranium on Monday outlined the potential for  “highly economic “ production at the Patterson Lake South (PLS) project in the Athabasca basin of Saskatchewan by focusing on an underground-only mining scenario.

Shifting to an underground-only option, as opposed to the hybrid mine approach of underground and openpit mining outlined in an earlier PFS, Fission has reduced the construction timeline of the mine at the Triple R deposit at PLS by one year and slashed the capital costs by one fifth, while still enjoying a strong return on investment.

The underground-only PFS reduced the construction time line from four years contemplated in the hybrid PFS, to three years. The capital costs fell from C$1.50-billion to C$1.18-billion, with a post-tax payback period estimated at 2.5 years.

The after-tax internal rate of return is 25% and the project has a net present value, at an 8% discount, of C$702-million.

The study estimates that the Triple R mine will operate for about seven years at 1 000 t/d of ore, with 2.3-million tonnes to be processed over the life-of-mine (LoM), containing 81.4-million pounds of uranium oxide (U₃O₈). LoM operating costs reduced from C$274/t to C$328/t.

The mine will produce 78.7-million pounds of U₃O₈, averaging at 13.1-million pounds a year for the first five years. This compares with 87.55-million pounds in the hybrid PFS.

At a uranium price forecast of $50/lb, the Triple R mine should generate gross revenue of C$5.25-million, which would earn the Saskatchewan government C$381-million in royalties.

“We are delighted by the results and have demonstrated the flexibility of the Triple R to be mined by multiple methods.  Fission is now able to transition confidently into the feasibility study phase,” commented president, COO and chief geologist Ross McElroy.

ENVIRO IMPACT

The underground-only option also substantially reduces the mine’s environmental impact. The underground plan completely eliminates the need for a ring dyke, slurry wall, dewatering, and overburden removal that was included in the hybrid PFS.

Fission also said that the recovery of reserves near the overburden and bedrock contact would use artificial ground freezing technology drilled remotely from shore, which eliminated any disturbances into Patterson Lake., noting that artificial ground freezing had been used extensively at uranium deposits in the Athabasca basin.

Further, other than a freshwater intake pump, and treated effluent discharge point, all other infrastructure related to mining at PLS would be set back at least 100 m from the shoreline of Patterson Lake.

The revised mining method results in a reduction of about 90% of total mine-related earth movement from the hybrid PFS to the underground PFS to 5.4-million tonnes and a 58% reduction to the total disturbed area.