California gold hopeful Stratabound Minerals Corp has built some “green technology” into its basic economic plan for a mine at Fremont on the Mother Lode Gold Belt, saying there’s potential upside in its preliminary economic assessment.
Stratabound has about three million ounces at 1.9-2.2 grams per tonne in inferred and indicated resources outlined at Fremont in north central California, USA. CEO Kim Tyler said only about 1.4km of the 4km strike length estimated on the property had been evaluated.
“Only 35% of mineralised strike and two of four mineralised zones have been defined and evaluated to date,” he said.
“Most notably, the opportunity remains to expand the at-surface oxide/heap leach potential indicated by the 4km-long-by-285m-wide 0.03-5.21gpt gold-in-soil anomaly that covers the entire 4km strike length.
“Oxide heap leach is a conventional cost-efficient processing method already proven and functioning at Equinox Gold’s successfully operating gold mines in California.”
The circa-US$10 million-market-cap company’s PEA estimated an after-tax US$210 million net present value (5% discount rate) and 21% internal rate of return with a $1750/oz gold price for a project producing an average 118,000oz a year at AISC of $1082/oz for 11 years.
Start-up capex was put at $203m.
Tyler suggested: “We know we can improve on that.
“We’ve packed a lot of conservatism into this economic plan. We wanted to make sure it passed the stress test.
“And we wanted to pack some technology into it, including green technology.”
A “relatively new, however proven” Railveyor electric-powered, hybrid conveyor-rail system that would eliminate five diesel-powered haulage trucks in a very preliminary underground-to-surface plant haulage configuration was put forward as one decarbonisation option.
“Future studies will examine the use of the Railveyor in the pit configuration, as well as other electric green-equipment alternatives, automation and green technology that may be implemented as that sector continues to leap forward and become more cost-efficient,” Tyler said.
“The PEA further accounts for progressively backfilling the openpit and returning mine tails back underground as paste fill thereby minimising the footprint and more swiftly restoring the land back to its original state.”
Mining would focus on three small oxide starter pits and heap leaching in year one, with concurrent development of the mine Pine Tree-Josephine opencut.
A potential 4000t/day underground development at Pine Tree-Josephine would employ long-hole open stoping, with ore extracted with 10t-payload load-haul-dump units which would then tip material down a broken material pass to a Railveyor system on a main haulage level.
Privately-owned Canadian company Railveyor, formed in 1999, completed its first commercial deployment of its Railveyor system in South Africa in 2007.
Stratabound is currently aiming to advance exploration drilling at Fremont.