[miningmx.com] — ACID mine drainage in the East Rand Basin has claimed another operation, with Gold One saying it will close its Sub Nigel 1 shaft due to rising water levels.
Gold One used the Sub Nigel shaft primarily as a training facility; it contributed about 3% to the company’s total output during the quarter to end-March.
The shaft was earmarked to form part of Gold One’s Megamine assets to be transferred to Goliath Gold.
“The rising water levels are the result of the cessation of pumping at the nearby Grootvlei mine, which up until May 30 2011 was managed by Aurora Empowerment Systems on behalf of the provisional liquidators of the Pamodzi Gold group of companies,’ read a company statement issued on Wednesday.
“Aurora stopped pumping at Grootvlei during February of this year, following the removal of the mine’s underground pumps. Goliath Gold is of the considered opinion that it is unlikely that the pump station will be reinstated in the near future.’
The training centre would be relocated to Gold One’s flagship Modder East mine.
Gold One said the water level at Sub Nigel would reach a critical point around August 2011.
“(The company) is investigating the plugging of the. shaft, just below the Kimberley Reef horizon, in order to preserve certain underground workings for future use.’
Marius Keet, senior regional manager at the department of water affairs, said the current level of acid mine water in the East Rand Basin was 650m below surface.
He also pointed to the cessation of pumping at Grootvlei as the cause of the rising water level.
“We have nobody to talk to there,’ he said. “The liquidators are trying to find a buyer but it is going to cost a lot of money (to install and operate new pumps).’
Quoted by Sapa in April, former Pamodzi liquidator Enver Motala said there were four working pumps at Grootvlei when Aurora took over management of the mine late 2009. However, they did no maintenance “so matters got progressively worse’.
Grootvlei has historically maintained the mine water level at a depth of around 700m below surface in its Number 3 shaft.
Gold One CEO Neal Froneman was not immediately available to comment, but told Finweek in April that Megamine would not be affected by rising water in the basin, saying Goliath would go after virgin, unmined reef.
“As long as your access points and your mining operations don’t hole into the old working areas, then flooding won’t be a problem and you’ll only have the normal amount of mine water to deal with, such as we have encountered at Modder East.’
