It would appear that the South African government has been spurred into action to fight the threat of acid mine drainage (AMD), a poisonous side effect of underground mining. Faced with claims from environmentalists that, without action, acidic water would leach from the country’s disused mines to contaminate 80% of fresh water sources by 2015, the government established a ministerial taskforce to investigate the threat in late October.
Cabinet spokesman Vusi Mona said experts would probe the impact of AMD flowing out of disused mines into drinking water, especially around Johannesburg, and report back by the end of 2010. “Within six weeks they hope to come back to cabinet and say this is what has been found, and these are the allocations of the budget and financial implications of the investigation,” he said.
In 2011, the committee will also examine warnings from farmers and food retailers about how poor water quality could damage food production.
A month prior to the taskforce’s establishment, South Africa’s Chamber of Mines also committed itself to backing government efforts to tackle the crisis. “The industry is prepared to work with government to find solutions that would not only deal with underground flooding, but also eliminate potential harm to people in a sustainable manner,” said the Chamber of Mines’ chief executive, Mzolisi Diliza.
Waste legacy
The problem is deep seated, long term, and a classic example of how mining can leave an expensive legacy if not properly managed. The worst problems are around Johannesburg and its surrounding hinterland of Witwatersrand; a 50km-long stretch of underground reef where the country’s first major gold rush occurred 120 years ago.
In the past, the majority of mining companies in the Witwatersrand operated below the watertable, which forced them to pump leakage from their underground operations to the surface, where it was either treated or dispersed. However, from the 1950s, operations began to close down as they became uneconomical to mine. Consequently, the subterranean voids left behind began to fill with AMD, and to this day the polluted water continues to rise, threatening freshwater sources on the surface.
As companies closed their mining operations and moved on, it was left to the people still working underground to pump the rising water from the reef’s interlinked mines. In 2008, the last major mining company with an operating pump, East Rand Propriety Mines (ERPM) in Boksburg, was closed down, leaving the AMD to rise to the surface untreated.
Since 2002, Witwatersrand’s eastern and western geological basins have been flooded with AMD during periods of high rainfall, and in recent months the polluted water has threatened the high-profile World Heritage fossil site, the Cradle of Human Kind, as well as downtown Johannesburg.
Terence McCarthy of the School of Geosciences at Wits University, Johannesburg, said that, unless the problem was tackled within two years, AMD would begin to flood parts of the city, as well as the central watershed in the area.
The AMD in the city area is currently about 600m below surface and is rising by about 15m/mth, Prof McCarthy told a lecture at Wits in October. “The solution to the problem is relatively simple, however, and involves the establishment of pumping stations to pump the water to the surface for basic treatment,” he said, before warning that, at the current rate, the AMD would decant (rise) fully in about 2.5 years.
Treatment
Treatment options proposed by the industry and water utilities have included adding lime to the highly acidic water (which raises the pH level and helps to remove heavy metals), as well as setting up reverse-osmosis plants.
Other solutions involve reconstructing mine shafts to reduce water entry, flooding mine pits and even creating artificial wetlands.
However, it seems that the desire of government and industry to carry out in-depth research into the exact nature of the problem, and settle the question of liability, have slowed responses.
Prof McCarthy told Mining, People and the Environment that the issue of cost had arisen because the vast majority of mining companies responsible for AMD are no longer in existence.
“Mining companies tended to externalise the environmental costs of their operations and now that they are all gone there is no one left to pick up the cost. The biggest beneficiary of mining has been the state through profit-sharing with the mining companies and then taxation. Much of the country’s road infrastructure was paid for by the mines, so in the end I think we – as in the taxpayer – will have to pay the environmental bill,” he concluded.
Shared responsibility
Johannesburg-based mining and civil-engineering firm TWP’s environmental division chief, Alwyn Laas, believes the mining industry and government has a dual responsibility to tackle the pending AMD crisis.
He added that, contrary to environmentalists’ claims that the issue was not being tackled with enough urgency, both the mining sector and government were taking the threat very seriously.
“The hydrology of this catchment is very complex, and the exact extent of the AMD problem needs to be understood and quantified,” said Mr Laas. “The government and industry are taking an informative approach, so they have all the information on the table before any final decisions are taken.
“The government has made several changes to the mining and environmental legislation, and the mining industry has been forced to provide funding for rehabilitation of their sites – the Rehabilitation Trust Fund. These trust funds could be used to partially fund whatever solutions are agreed upon.TWP has investigated different treatment options and, although each has their pros and cons, the problem is manageable. I do, however, think that government and the mining industry have failed to transmit this message to the public properly,” he added.
However, Mariette Liefferink, chief executive of the Federation for a Sustainable Environment, takes a different view. “The industry informed parliament in 1999 that AMD would start to decant [rise] in 2002, and nothing has happened to tackle this issue since then. Consequently, fresh water sources have already been destroyed. The National Nuclear Regulator has declared many recreation dams radioactive because of the decanting.
“For instance, Robinson Lake [in Gauteng province] contains uranium levels 40,000 times above natural levels in fresh water. Unfortunately, what the govern-ment is doing is implementing a crisis management strategy when what we have needed all along is a proactive plan. If proper intervention is not implemented in the next few months it will be too late.”
Bill Corcoran is a reporter working with International News Services
Cabinet spokesman Vusi Mona said experts would probe the impact of AMD flowing out of disused mines into drinking water, especially around Johannesburg, and report back by the end of 2010. “Within six weeks they hope to come back to cabinet and say this is what has been found, and these are the allocations of the budget and financial implications of the investigation,” he said.
In 2011, the committee will also examine warnings from farmers and food retailers about how poor water quality could damage food production.
A month prior to the taskforce’s establishment, South Africa’s Chamber of Mines also committed itself to backing government efforts to tackle the crisis. “The industry is prepared to work with government to find solutions that would not only deal with underground flooding, but also eliminate potential harm to people in a sustainable manner,” said the Chamber of Mines’ chief executive, Mzolisi Diliza.
Waste legacy
The problem is deep seated, long term, and a classic example of how mining can leave an expensive legacy if not properly managed. The worst problems are around Johannesburg and its surrounding hinterland of Witwatersrand; a 50km-long stretch of underground reef where the country’s first major gold rush occurred 120 years ago.In the past, the majority of mining companies in the Witwatersrand operated below the watertable, which forced them to pump leakage from their underground operations to the surface, where it was either treated or dispersed. However, from the 1950s, operations began to close down as they became uneconomical to mine. Consequently, the subterranean voids left behind began to fill with AMD, and to this day the polluted water continues to rise, threatening freshwater sources on the surface.
As companies closed their mining operations and moved on, it was left to the people still working underground to pump the rising water from the reef’s interlinked mines. In 2008, the last major mining company with an operating pump, East Rand Propriety Mines (ERPM) in Boksburg, was closed down, leaving the AMD to rise to the surface untreated.
Since 2002, Witwatersrand’s eastern and western geological basins have been flooded with AMD during periods of high rainfall, and in recent months the polluted water has threatened the high-profile World Heritage fossil site, the Cradle of Human Kind, as well as downtown Johannesburg.
Terence McCarthy of the School of Geosciences at Wits University, Johannesburg, said that, unless the problem was tackled within two years, AMD would begin to flood parts of the city, as well as the central watershed in the area.
The AMD in the city area is currently about 600m below surface and is rising by about 15m/mth, Prof McCarthy told a lecture at Wits in October. “The solution to the problem is relatively simple, however, and involves the establishment of pumping stations to pump the water to the surface for basic treatment,” he said, before warning that, at the current rate, the AMD would decant (rise) fully in about 2.5 years.
Treatment
Treatment options proposed by the industry and water utilities have included adding lime to the highly acidic water (which raises the pH level and helps to remove heavy metals), as well as setting up reverse-osmosis plants.Other solutions involve reconstructing mine shafts to reduce water entry, flooding mine pits and even creating artificial wetlands.
However, it seems that the desire of government and industry to carry out in-depth research into the exact nature of the problem, and settle the question of liability, have slowed responses.
Prof McCarthy told Mining, People and the Environment that the issue of cost had arisen because the vast majority of mining companies responsible for AMD are no longer in existence.
“Mining companies tended to externalise the environmental costs of their operations and now that they are all gone there is no one left to pick up the cost. The biggest beneficiary of mining has been the state through profit-sharing with the mining companies and then taxation. Much of the country’s road infrastructure was paid for by the mines, so in the end I think we – as in the taxpayer – will have to pay the environmental bill,” he concluded.
Shared responsibility
Johannesburg-based mining and civil-engineering firm TWP’s environmental division chief, Alwyn Laas, believes the mining industry and government has a dual responsibility to tackle the pending AMD crisis. He added that, contrary to environmentalists’ claims that the issue was not being tackled with enough urgency, both the mining sector and government were taking the threat very seriously.
“The hydrology of this catchment is very complex, and the exact extent of the AMD problem needs to be understood and quantified,” said Mr Laas. “The government and industry are taking an informative approach, so they have all the information on the table before any final decisions are taken.
“The government has made several changes to the mining and environmental legislation, and the mining industry has been forced to provide funding for rehabilitation of their sites – the Rehabilitation Trust Fund. These trust funds could be used to partially fund whatever solutions are agreed upon.TWP has investigated different treatment options and, although each has their pros and cons, the problem is manageable. I do, however, think that government and the mining industry have failed to transmit this message to the public properly,” he added.
However, Mariette Liefferink, chief executive of the Federation for a Sustainable Environment, takes a different view. “The industry informed parliament in 1999 that AMD would start to decant [rise] in 2002, and nothing has happened to tackle this issue since then. Consequently, fresh water sources have already been destroyed. The National Nuclear Regulator has declared many recreation dams radioactive because of the decanting.
“For instance, Robinson Lake [in Gauteng province] contains uranium levels 40,000 times above natural levels in fresh water. Unfortunately, what the govern-ment is doing is implementing a crisis management strategy when what we have needed all along is a proactive plan. If proper intervention is not implemented in the next few months it will be too late.”
Bill Corcoran is a reporter working with International News Services