JOHANNESBURG (miningweekly.com) – Southern African diamond mining, development and exploration company DiamondCorp has, following completion of back-filling activities and almost two weeks ahead of schedule, resumed development tunnelling on the 290 m doming level at the Lace mine, in the Free State.
The company said in a market update on Friday that tunnelling on the 290 m level was now progressing in competent high-grade K4 kimberlite, following successful installation of steel arched sets for a 10 m section through the centre of the slot drive cross cut on this level.
Tunnel advances were now being achieved at the originally planned rate, as the kimberlite contained significantly less internal waste than the lower-grade K6 kimberlite on the southern side of the pipe, through which the development tunnels needed to traverse before entering the high-grade Upper K4 (UK4) mining block.
The sets provided a safe canopy for workers and machinery that needed to access this level for the start of drilling and blasting of the slot between the 290 m and 310 m production level.
The slot provided the initial ramp-up in mining tonnages from the UK4 block, which was on schedule to start next month.
CEO Paul Loudon said the resumption of development work on the 290 m level, combined with the commissioning, last week, of the 400 t/h
conveyor belt system from the first production level, meant that many of the operational challenges the mine had faced in recent months had now been overcome.
“The overall development and production timetable, however, remains behind schedule, as previously announced,” he noted.