Modern Mining July 2018

MINING News

Sanbrado to be a plus 200 000 oz/a gold producer

West African Resources (WAF), dual listed on the ASX and TSX-V, has announced the results of its updated Feasibility Study, pre- pared in accordance with the requirements of the 2012 JORC Code and NI 43-101, for the Sanbrado gold project in Burkina Faso. The company is hoping to have Sanbrado in production in 2020. The study envisages an initial 11-year mine life including 4,5 years of under- ground mining, with strong early cashflow and a rapid payback of capital. The average annual production over the first five years of operation would be 211 000 ounces. Sanbrado’s ore reserves have been updated in the study to a probable ore reserve of 20,4 Mt at 2,4 g/t Au for 1,57 Moz of gold. The project comprises several open pits, all within 1-2 km of the plant site, and an underground mine accessed through a portal at the south-eastern end of the M1 South open pit. The plant com- prises a conventional SABC milling circuit, gravity and CIL processing with a nominal throughput capacity of 2 Mt/a. The project will be a conventional, low cost and high margin operation with LOM All in Sustaining Costs (AISC) of US$640/oz. This is a result of the significant proportion of oxide and transition material in the mine schedule and the free-milling nature of all ore types (average LOM recovery of 92,9%), low reagent consumption and a high com- ponent of gravity recoverable gold. The estimated project capital cost is US$185 million, inclusive of all open-pit and underground pre-production mining and development costs, contingencies, duties and taxes. At the base case gold price of US$1 300/oz and using a 5 % discount rate, the project generates a post-tax NPV of US$405 million and an IRR of 49 % with a post-tax payback period of 16 months following commissioning. The majority of the defined mineral resources suitable for open-pit mining are within 200 m depth from the surface and of a lode-style mineralisation. The material to be excavated will be predominantly free dig from surface with blasting required deeper in the oxidation profile. Given these conditions, conventional open-pit mining techniques using drill and blast with mate- rial movement by hydraulic excavators and trucks will be employed. The project scale

Sanbrado is located 90 km south-east of Ouagadougou, Burkina Faso’s capital.

suits 120 to 200 tonne class excavators in a backhoe configuration matched to 95 tonne class mine haul trucks. In addition to the open-pit resources, the M1 South deposit has a steeply dip- ping, high grade zone that extends to depth and is suitable for exploitation by underground mining methods using conventional jumbo development. The planned mining method is uphole retreat bench stoping with loose rock fill and cemented fill where necessary. Mining activities will be undertaken by experienced open-pit and underground mining contractors, with West African Resources retaining responsibility for tech- nical services comprising mine planning, production scheduling, grade control, sur- veying, supervision and management of contract mining operations. The main M5 pit is 2 km long and aver- ages 430 m wide and 205 m deep at the southern end. The pit has been designed so the southern higher grade portion can be mined independently of the northern portion of the pit. Both the northern and southern pits will be mined in two stages, an initial starter pit and then a cutback to final limits, in order to target higher grade earlier in the schedule and defer waste. The M1 deposit will be mined in two

pits, a north and a south pit. The M1 South pit has been limited to a depth of 120 m from surface, as optimisation of the mine schedule and project cash flow indicated that this provided the best interface with the underground mine. The M1 South pit design incorporates an underground portal in the south-east wall. To enable the earliest possible development of the underground workings, the southern sec- tion of the pit will be mined to a depth of 30 m to enable the portal to be devel- oped in fresh rock. The final M1 South pit is 570 m long by 290 m wide and 120 m deep. The M1 North pit is 350 m long by 240 m wide and 90 m deep. The M3 deposit also has two small, pre- dominantly oxide, pits less than 40 mdeep. The Sanbrado process plant will have a nameplate throughput of 2 Mt/a, with an availability of 8 000 hours per annum and a nominal capacity of 250 tonnes per hour (tph). It will be located south-east of the M5 pit. The plant is to be fed predomi- nantly from the M1 and M5 deposits, with only small volumes of material supplied by the M3 pit. A heavy fuel oil (HFO) power station will be constructed at the process plant by an independent power provider (IPP) under a build-own-operate (BOO) agreement. 

8  MODERN MINING  July 2018