Engineering & Mining Journal

JUL 2019

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 67

REGIONAL NEWS - AFRICA 14 E&MJ • JULY 2019 West African Resources Building Sanbrado Mine in Burkina Faso West African Resources has begun con- struction of its Sanbrado open-pit/under- ground gold mine in Burkina Faso, 90 kilometers (km) east-southeast of Ouaga- dougou, the nation's capital. The compa- ny said it started construction because of very favorable results from an optimized feasibility study completed in April. All long-lead items have been ordered, and the first gold pour is scheduled for the third quarter of 2020. Production during the first year of operation is planned at 301,000 ounces (oz) of gold at all-in sus- taining costs of $497/oz. Average annual production over the first five years of Sanbrado mine life is estimated at 217,000 oz per year (oz/y) of gold. Life-of-mine production is esti- mated at an average of 153,000 oz/y over the current projected 10-year mine life. Preproduction capital costs are esti- mated at $186 million. Probable gold re- serves currently stand at 1.7 million oz in 21.6 million metric tons (mt) at a grade of 2.4 grams (g)/mt. West African Resources Managing Di- rector Richard Hyde said, "The optimized feasibility study confirms that Sanbrado is a high-margin gold project, producing 217,000 oz/y of at all-in sustaining costs of $563/oz over the first five years of mine life. "Recent deep high-grade intercepts demonstrate the potential to extend re- serves and increase annual production post-year six with additional infill and ex- tensional drilling." Sanbrado's underground high-grade gold mineralization is associated with quartz vein and veinlet arrays, silica, sul- phide- and carbonate-albite, and tourma- line-biotite alteration. Gold is visible and is mainly associated with minor pyrite, chalcopyrite, and arsenopyrite dissemina- tions and stringers. The currently defined economic min- eralization is sub-vertical, with a strike length of up to 120 m and widths of up to 50 m over two discrete lenses. It remains open at depth. The underground mine will be devel- oped using conventional two-boom jum- bos capable of face advance and instal- lation of ground support. Access will be by decline, starting from a box-cut and portal to the immediate south-west of the M1 South open pit. Underground mining will be by long- hole open stoping, progressing upwards from the base of each lift. Stope filling uses a combination of cemented aggre- gate fill, cemented rock fill, and develop- ment waste rock, depending on whether or not fill needs to be exposed to mine adjacent stopes. The deposit has been divided into four lifts, each of four or five levels. Within these lifts, stoping progresses upward from the base of the lift. The final level in each lift is mined as a pillar recovery be- neath the lift above, or the open pit in the case of lift 1. The crown between the un- derground mine and the open pit will be mined after the completion other stopes. A level interval of 25 m was chosen to fit with the geotechnical conditions and variable geometry of the orebody, as well as to ensure maximum recovery of what is a valuable resource. West African Resources is 90% owner and operator of the Sanbrado project. The government of Burkina Faso has a 10% free-carried interest. 43 Illegal Miner Fatalities at Kamoto Copper Forty-three illegal artisanal miners were killed at Kamoto Copper Co.'s (KCC), a subsidiary of Glencore, mining conces- sions in the Kolwezi area in the Democrat- ic Republic of the Congo, according to lo- cal news sources on Friday, June 28. KCC said the miners were working two galleries in benches overlooking the extraction area when the galleries caved in on Thursday, June 27. The total death toll was origi- nally 19, but increased when more people were discovered under the collapse. The incident was not linked to KCC, but KCC said it continues to assist in search and rescue operations with the local author- ities. KCC said on average, it is seeing in- trusions of 2,000 illegal artisanal miners per day. "This has presented a significant risk to its employees, operating equip- ment and the illegal artisanal miners themselves," the company said. Orion Completes BFS on Prieska Project Orion Minerals Ltd. announced the pos- itive outcomes of a Bankable Feasibility Study (BFS) for the Foundation Phase of its Prieska copper-zinc project, located in the Northern Cape Province of South Af- rica. The BFS highlights the Prieska proj- ect as a long life, high-margin copper and zinc development project, with opportuni- ties for future growth. The NPV is based on long-term metal prices of $6,834/metric ton ($3.11/lb) for copper and $2,756/mt ($1.25/lb) for zinc. The estimated capital payback period is less than three years from first production. The Foundation Phase runs for 10 years of run-of-mine production at a de- sign ore processing rate of 2.4 million mt per year (mt/y). This phase exploits the portions of the Prieska deposit that were upgraded to indicated and inferred miner- al resources from the first surface-based drilling campaign conducted between 2017 and 2018. The production target is composed of 65% probable ore reserves and 35% inferred mineral resources, with ore reserves predominating during the early stages of the mining plan. Both underground and surface mining methods are planned to be used in con- junction with conventional froth-flotation concentration to produce differentiated copper and zinc concentrates for export. Peak funding requirements amount to $A378 million including a 10% con- tingency allowance. This would occur in the third year of the capital expenditure (CAPEX) program. CAPEX incorporates establishment costs for open-pit mining, which is planned at the end of the Foun- dation Phase. Payback is planned to occur five years from the start of construction or 2.9 years from the start of production. Unit all-in-sustaining costs (AISC) over the duration of the Foundation Phase would be $1.72/lb copper equiva- lent metal sold. The realized price (net of smelter charges) would be $3.08/lb cop- per-equivalent metal sold. The operating break-even grade is estimated at 1.2% copper equivalent, well below the ore re- serves grade of 2.1% copper.

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