JOHANNESBURG (miningweekly.com) - The pumping crisis reported by Pamodzi Gold held no immediate or even short-term threat to either the safety of Aflease Gold employees nor to the company's mining operation at Sub Nigel and, in particular, no threat whatsoever to the company's Modder East operations, Aflease CEO Neal Froneman said on Friday.
Froneman told Mining Weekly Online that gold mining at Sub Nigel currently took place 150 m above the level at which the Grootvlei mine would start flooding should cash-strapped Pamodzi Gold cease pumping water out of Grootvlei.
If flooding did take place, the water would rise at an estimated rate of 300 mm a day, taking more than a year to reach the level at which the company was currently mining, a risk which had been factored into the scale of the recommissioning operation.
"Our flagship project Modder East is not associated at all with the East Rand Basin and therefore not at risk. Sub Nigel is interconnected into the East Rand Basin, but that has always been known and understood and that's why we have gone back into Sub Nigel in a limited way," Froneman reiterated to Mining Weekly Online.
Froneman said that the decision to recommission Sub Nigel in phases - the first phase of which was completed at a cost of R15-million - was taken specifically with that risk in mind.
Sub Nigel's resuscitation generates revenue ahead of the full commissioning of Modder East, where Sub Nigel ore would be processed during the build-up phase.
The mine was operating at a cash cost of $500/oz, which included the cost of transporting the ore 32 km by road to the Modder East plant.
Its ore was being stockpiled until May, when the Modder East plant would be brought into production.
Modder East would produce its first gold in the last quarter of 2009.
Sub Nigel would initially produce at the moderate rate of 6 000 t/m compared with Modder East's eventual 100 000 t/m, "small in the big scheme of things", but was an important training ground for Modder East.
In its heyday, Sub Nigel, situated 1 km north-west of the town of Nigel, produced 15-million ounces of gold from the Nigel reef between 1909 and 1971. Nearly 30-million tons of ore were milled during that period, at an average head grade of 15,7 g/t.