JOHANNESBURG – The water treatment plant at the Grootvlei mine near Springs will flood with acid mine water in five days, closing down operations, if action is not taken, the Water Affairs Department said on Tuesday.

"The plant is only pumping 40 megalitres of acid mine water a day, but it needs to pump 108 megalitres a day to stop it from flooding," the department's acting director of institutional establishment, Marius Keet said during a visit to the mine, owned by Aurora Empowerment Systems.

"Fortunately Aurora have said they have acquired the equipment to pump more and will be installing it in the next few days."

The department's portfolio committee, representatives from the Departments of Water Affairs and Mineral Resources, and members of the DA were also part of the visiting delegation.

Acid mine drainage was affecting the Western, Central and Eastern Basins of the Witwatersrand gold fields area, which had negatively affected the Vaal and the Crocodile River systems.

Acid water is formed underground when old shafts and tunnels fill up. The water oxidises with the sulphide mineral iron pyrite, better known as fool's gold. The water then fills the mine and starts decanting into the environment, in a process known as acid mine drainage.

Keet said if the toxic water, a legacy of 120 years of gold mining in the region, was left to rise from underground, it would flood the basins and have catastrophic consequences for the environment, human and animal life and future mining.

The polluted water was currently 600 metres below Johannesburg and, if left unchecked, would spill onto the streets in about 18 months, damaging buildings in the CBD.

Aurora's general manager Louis Lamsley said they were "struggling to keep their heads above water".

"We are an extremely stressed operation financially," he said referring to claims the company had paid up to R100 million in the last nine months to maintain the mine water treatment plant, which still seemed to be on the brink of disaster.

Grootvlei was the only mine in the Eastern Basin pumping out acid water. It only pumped intermittently and had been accused of only partially treating the water and discharging it into the Blesbok Spruit.

The department opened a criminal case against Aurora after it allegedly failed to comply with a directive to treat the pumped water before discharging it. The matter was currently under investigation by the police and the Blue Scorpions.

Acid mine water started flooding the pump station in June after workers, angered by months of not being paid, downed tools.

"We are supposed to be receiving a R5-million subsidy from the state, but we have not received this since October last year," said Zondwa Mandela, Aurora's managing director and former president
Nelson Mandela's grandson.

"It costs R6,5-million [per month] to run the plant," he said.

Aurora called on government to assist them financially.

Chairwoman of the department of water affairs' portfolio committee Maggie Sotyu said: "We are visiting the areas so we can assess what needs to be done to fix the problem, and we will compile a report to hand to Parliament in a month's time, but the situation is serious so we will need to intervene before that."