Engineering & Mining Journal

FEB 2018

Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr

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Page 15 of 59

REGIONAL NEWS - AUSTRALIA/OCEANIA 14 E&MJ • FEBRUARY 2018 Gold miner St. Barbara has begun one of the longest drill holes in Australian min- ing history to extend the life of the Gwalia gold mine near Leonora, according to The West Australian. Located 230 km north of Kalgoorlie-Boulder, St. Barbara is pouring more than $1 million into the campaign to find gold 2,600 m below the original Sons of Gwalia mine. Resources at the 250,000-ounce- per-year (oz/y) gold mine, considered the deepest trucking mine in the world, now extend to 2,200 m below surface, with a mine reserve life stretching to 2024. Managing Director Bob Vassie said the adventurous exploration campaign was planned to prepare for the mine's future. "We've got this incredible ore body that's been mined since the late 1890s on and off, and now it's doing better than it's ever done, with some record production and great cash generation," he said. "We know the ore body just continues in a straight line. "I think it was about three years ago we didn't have any holes under 1,800 m below surface, that's where our reserves had cut off, but we knew the ore body seemed to continue. "In this particular hole, in one regard, we don't need to drill it right now ... we wouldn't be down there for years and years to come. "But it's more of a strategic hole." The diamond drill hole, being execut- ed by DDH1 Drilling, is expected to cost about $1.6 million including associated costs, stretch 2,950 m from its collar to the target, and take four months to com- plete with assays to follow soon after. While it is expected to fall short of a hole drilled by KCGM at the Super Pit in 2015, which reportedly ended at a length of 3,011.5 m, it is among the deepest mineral exploration targets ever tested in Australia. Updated Feasibility Study Enhances Mount Peake TNG Ltd. reported the results an updated feasibility study and financial model for its 100% owned Mount Peake vanadium-tita- nium-iron project in Australia's Northern Territory. The results reconfirm and en- hance outcomes reported in a definitive feasibility study completed in 2015. The new study assumes open-pit min- ing followed by production of magnetite concentrate at Mount Peake. Life-of-mine beneficiation feed material is estimated at 81 million metric tons (mt) at an average grade of 0.37% V 2 O 5 , 6.87% TiO 2 , and 26.38% Fe. This includes an ore reserve of about 41.1 million mt, with the remaining material sourced from measured and indi- cated resources. Concentrate produced at Mount Peake will be trucked to a rail siding and then railed approximately 1,250 km north to a TIVAN process plant approximately 10 km from Darwin Port. TIVAN is a patented TNG process. After extensive refinement, the process now utilizes a proprietary method of vanadium extraction that avoids complex and capex-intensive chloride bal- ancing and operates with a significantly smaller acid-regeneration circuit. The flow- sheet includes feed preparation, leaching, extraction, and acid regeneration. The plant will have an initial design processing capacity to treat 900,000 mt/y of magnetite concentrate. The updated Mount Peake feasibility study estimates preproduction capital ex- penditure of A$853 million, including all infrastructure, access/haul roads, mining, rail works, camp, water supply, concen- trator, tailing dam, TIVAN process plant, and port handling costs. A Stage Two expansion is proposed to increase maximum TIVAN plant through- put to 1.8 million mt/y in production year five. The capacity of the concentrator and process plant would also double. Stage 2 capex costs of A$969 million would be paid out of operating revenue. The TIVAN plant will produce high-pu- rity V 2 O 5 , pigment-grade TiO 2 , and pig iron. The high-purity V 2 O 5 product will be suitable for use in both the ferro-vanadium and the emerging vanadium redox battery market sectors. Associated downstream plants will produce high-grade titanium pigment and pig iron. While these addi- tional plant facilities increase the capital requirement of the Mount Peake project, the higher revenues to be achieved from the higher-value end products provide TNG with the potential for an early pay- back of three years and an exceptional internal rate of return. In addition, the products have well-understood markets, transparent pricing, and ready demand. The TIVAN process plant is planned to have an operating life of approximately 40 years, longer than the current planned Mount Peake project life. Drilling results have indicated the potential to find addi- tional ore in the Mount Peake area. This potential for additional long-life revenue streams has not been incorporated into the updated feasibility study. St. Barbara Drills Deep for Gwalia Gold St. Barbara senior resource geologist Adrian Diaz (left) and DDH1 Drilling supervisor Alexander Phillips at the site of what could be one of Australia's deepest mineral exploration holes.

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