Modern Mining June 2015

MINING IN AFRICA

Revised PFS delivers boost for underground mining at Syama

I n March 2014 Resolute released results from a PFS for a proposed underground operation at the Syama project. The study – completed by independent ex- perts Snowden Mining Industry Consul- tants – identified an opportunity to migrate to a long-term, underground mining operation by exploiting the extensive mineral resource be- neath the open pit. During 2014 the company completed a 13 600 m drilling programme to infill and extend the underground resource. The results of this drilling were reported throughout the year and were highlighted by many broad high-grade intercepts. In March 2015 Resolute announced that ore contained within the Stage 2 open-pit mine plan was best extracted from underground, pro- viding greater return on capital and a smoother cash flow profile. It was subsequently con- cluded that a revised Underground PFS would incorporate the Stage 2 open-pit resource, as well as the remodelled deeper resources from the highly successful drilling programme, to determine the operational and financial improvements compared to the earlier study. Summary of revised PFS analysis Through geotechnical analysis and investiga- tion of various underground mining methods, operations at strong cash margins. The updated study also delivers a significant increase in underground ore reserves, incorporating recent high grade results from diamond drilling conducted over 2014, including the previous Stage 2 open-pit resource. Australia’s Resolute Mining, listed on the ASX, reports that the results from an independent revision of the Underground Pre-Feasibility Study (PFS) at its Syama gold mine in Mali confirm that an early move to underground mining in 2016 will produce robust economics with

Syama cross-section displaying decline and level development.

Snowden determined that the orebody footprint was sufficiently large for a caving operation to be developed and selected traditional SLC (Sub Level Caving) as the preferred mining method for the following reasons:  The orebody geometry and geotechnical con- ditions are suited to SLC.  SLC is a highly mechanised mining method, well-understood and used in many locations around the world; it can deliver the required production rate to replace open-pit produc- tion (about 2 Mt/a) at an acceptable cost.  The subsidence zone will not impact on or affect critical infrastructure.  Geotechnical conditions are unfavourable for more traditional open-stoping methods, mak- ing them lower production rate and higher cost options.  Resolute successfully uses a similar method at its Mt Wright operations in Ravenswood, Queensland, Australia. The mine design parameters have been based on Australian experience including Mt Wright and other typical Australian SLC operations. Specific mine design parameters may change as more data and information becomes available through the Definitive Feasibility Study (DFS)

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