Modern Mining December 2015

MINING News

C-Cut Expansion at Cullinan running ahead of schedule

In addition to the upgrade and expansion of surface infrastructure, the expansion includes the deepening of both the men & material shaft (3 Shaft) from 805 level to 885 level and the rock hoist- ing shaft (1 Shaft) from 580 level to 934 level. It also includes new north and south declines and conveyors; heavy-duty, high volume north and south crushers; two big storage silos and the requisite access area development. Murray & Roberts Cementation’s con- tract, awarded in August 2012, includes the shaft-sinking extensions for both 1 Shaft and 3 Shaft. The company believes that its contribution towards the project’s success continues to play a pivotal role in maintaining the development schedule but, more importantly, moving ahead of it. The actual underground project scope was recently at 64 % complete and, to date, equates to about 2 km of develop- ment ahead of the original targets, Cloete notes. The Murray & Roberts Cementation sinking team has been particularly effec- tive with time utilisation.“We have focused intensively and simultaneously on all proj- ect aspects and variables as well as upfront scheduling which utilises our 307 employ- ees’ time effectively. This has minimised delays resulting from unforeseen sinking challenges for example,” explains Robbie Duyts, Murray & Roberts Cementation’s Senior Project Manager. To date, sinking at 3 Shaft (7 m diam- eter/6 m diameter lined) has been completed and Murray & Rober ts Cementation is working to complete equipping and lining shortly. Sinking at 1 Shaft (9,6 m x 2,3 m lined) is also well advanced and Duyts notes that sinking will reach the loading box by December (2015). The raiseboring technique has been used for both shafts – another project aspect which has ensured on-schedule develop- ment rates as equipping and sinking can occur simultaneously. In addition to the shaft-sinking con- tract, Murray & Roberts Cementation has also started with the slipe and line for the two storage silos (13 m x 36 m). It has also facilitated engineering for the Koepe wind- ers – the first was completed in December 2014 and the second is due for completion this month (December 2015). 

Access to 3 Shaft deepening and view of the installation of pump and water column which will assist with water management.

Exploration work undertaken by Sarama defined a 15 km long gold corridor high- lighted by gold-in-soil anomalies and extensive artisanal mining, which on aver- age are within a 15 km radius of the NLGM. Sarama has expended a total of US$1,8 mil- lion on exploring the licences. The acquired gold corridor will be the focus of follow up exploration programmes once Aureus achieves a cash flow positive position, with the objective of defining new gold deposits.  Once in full production, the new C-Cut block will increase Cullinan’s Run-Of-Mine (ROM) production from 2,5 Mt/a in FY 2015 to 4 Mt/a by FY 2019. By accessing the C-Cut block and mining high grade undi- luted ore, ROM grades are set to increase from 24 cpht in FY 2015 to in excess of 50 cpht in FY 2019. As a result, ROM carat production is expected to increase from 0,6 Mct in FY 2015 to +2 Mct/a by FY 2019. beyond 2016,” says Petra’s Mining Projects Manager, Andre Cloete. The C-Cut Phase 1 Expansion project entails the development and construc- tion of a new block cave on the western side of the orebody, 200 m below the cur- rent operational B block mining horizons, situated between 645 level and 885 level below surface.

The underground portion of the C-Cut Phase 1 Expansion project at Petra Diamonds’ Cullinan mine, initiated in 2011 and due for completion in 2019, has already been recognised as a major success. Shaft-sinking specialist Murray & Roberts Cementation believes that its ded- ication to its portion of the overall contract has helped position the project well ahead of schedule.

The expansion project is transforming Cullinan mine and will deliver a new oper- ation which will perform strongly during its last years of operational life. “The new mine gives us access to greater volumes of fresh, high grade undiluted ore for at least another 16 years. It will also ensure the mine retains its status as one of Petra Diamonds’ flagship diamond mines well Aureus to acquire ground close to New Liberty

Aureus Mining Inc, the TSX- and AIM-listed miner which owns the newly opened New Liberty Gold Mine (NLGM) in Liberia, has agreed to acquire three exploration licences from Sarama Resources. These licences are contiguous to Aureus’ Bea Mountain mining licence and are located close to the NLGM. Following the comple- tion of the acquisition, Aureus will have 100 % ownership of the licences and the company’s total land portfolio will increase to 1 683 km 2 from 1 402 km 2 .

4  MODERN MINING  December 2015