Mining Weekly

A century-old gold-mine on Johannesburg’s East Rand is making a comeback, and man- agement is confident that decades of turmoil are now something of the past.

East Rand Proprietary Mines (ERPM) is set to become a 400 kg/m producer at the beginning of next year, the mine’s operations director, Grant Dempsey, told Mining Weekly in an exclusive interview.

But Boksburg’s 110-year-old mine has faced some rocky times. Even in February this year, an underground fire at ERPM’s Far East Vertical shaft cast doubt on the mine’s survival. The shaft accounts for about 85% of ERPM’s production.

Yet it is making a speedy recovery, having already passed management’s proposed production targets. In June, ERPM produced 268 kg of gold, seven kilograms more than anticipated and, this month, the mine will produce 280 kg – again above expectations.

Dempsey said the mine has virtually recovered from the fire, which burned itself out in April, but cost R15-million to contain. This figure also includes the loss of 130 kg of gold production. However, the road to complete recovery is well charted.

Production figures of 300 kg and 320 kg are anticipated for August and September respectively. And a new surface-mining project is set to add a further 78 kg to ERPM’s monthly production, increasing the mine’s normal output of 135 000 oz/y.

The mine’s general manager, Louwtjie Lourens, said the strategy to mine the Cason dump has already been finalised and mining, on a small scale, will begin in December. Full production is expected to be reached in February next year, when some 200 000 t/m will be mined at the 24-hour, seven-day-a-week operation.

This is not the first time that attempts have been made to reclaim gold from the dump. A similar project was started by the mine’s former management, before the company went into liquidation in 1999.

When this operation was launched, local communities vehemently opposed the surface-mining activities, on grounds of excessive dust that emanated from the operation. This problem, explained Lourens, has been solved.

“We will mine the dump from the south side and not from the north, as was done originally. Thus, the dump itself will shield the operation from the wind,” he stated.

A R46,5-million loan has been secured for the project, with 60% coming from South Africa’s State-owned Industrial Development Corporation and 40% from Durban Roodepoort Deep (DRD). ERPM is a wholly-owned subsidiary of Crown Gold Recoveries, a black economic empowerment joint venture between Khumo Bathong Holdings (60%) and DRD (40%).

The Cason dump-mining project, which could create some 150 new jobs, will have a life of about eight years and gold will be recovered at a cost of R73 000/kg. Currently, ERPM employs about 2 400 people.

Dempsey explained that the gold-recovery operation would use a straightforward carbon-in-leach process.

The R46,5-million would be used for infrastructure upgrading, which will include the recommissioning of disused parts of ERPM’s processing plant at its Central shaft, located between Boksburg and Germiston.

“The plant has a capacity of 280 000 t/m and, currently, we are only utilising 55 000 t/m of that capacity,” Dempsey added.

Part of the capital expenditure will be used to construct a pipeline from the dump to the processing plant and then to a slimes dam in Benoni, while reclaimed gold will be eluted at Crown Gold Recoveries’ City plant.

“ERPM has a lot of upside and could easily become a force to be reckoned with,” commented Lourens.

The mine’s current reserves are about 1,99-million ounces, while resources are estimated at some 8,57-million ounces. Recently, the life-of-mine had been extended from nine years to eleven years, and Lourens and Dempsey agree that there is much potential to turn further resources into reserves. To this end, management also has an eye on a number of other orebodies, but says it is too early to reveal details.

ERPM’s new lease of life can be ascribed to a dynamic management team, under the leadership of Khumo Bathong chairperson Dr Paseka Ncholo.