JOHANNESBURG, Dec 3 (IPS) - Large gold-mining companies operating to the west of South Africa's commercial centre, Johannesburg, stand accused of contaminating a number of water sources with radioactive pollutants.
One case involves the Wonderfontein Spruit ("water course", in Afrikaans): a stream that runs 90 kilometres from the outskirts of Johannesburg to the south-west past the towns of Krugersdorp, Bekkersdal, Carletonville and Khutsong, before flowing into the Mooi River near Potchefstroom.
Mariette Liefferink, an environmental activist, blames the mines for the high concentrations of heavy metals such as arsenic, cadmium, copper cobalt and zinc in the waters of the spruit. She is particularly troubled by the levels of uranium, which gives off radioactive by-products such as polonium and lead.
"The Wonderfontein Spruit is of major concern to us because every year the gold mines discharge 50 tonnes of uranium into the receiving water course. The Water Research Commission (a parastatal research body) has found that there are approximately 1,100 milligrammes per kilogramme of uranium in the upper Wonderfontein Spruit, and 900 milligrammes per kilogramme in the lower Wonderfontein Spruit area."
Heavy metal concentrations are higher in the upper reaches of the river because a large percentage of the pollutants sink into the sediments as water flows downstream. This means that under normal circumstances water tests in lower areas do not cause great concern, and users may feel that they are not under threat from heavy metal contaminants.
If, however, the sediments are in any way disturbed -- by cattle, or children playing in the river, for example -- the uranium can easily be dislodged from the sediments and reabsorbed into the water.
Government bodies have commissioned several studies to ascertain the gravity of the water pollution in the Wonderfontein Spruit. The most recent study, known as the Brenk report, was commissioned by the National Nuclear Regulator (NNR) -- a governmental body set up to monitor and regulate the production and use of nuclear materials -- and compiled under the direction of German physicist Rainer Barthel.
Initially government was so embarrassed by the Brenk report that the NNR refused to release it to the public, and as Barthel was due to present his findings to the Environmin 2007 conference on Jul. 24-25, organisers of this event were told to withdraw his invitation.
When the Brenk Report was eventually made public in August, it resulted in a number of contradictory messages.
Harmony Gold -- the world’s fifth largest gold producer, and one of the mines responsible for the uranium discharge -- relayed to farmers on its lands a directive from the NNR saying that livestock may not consume water from the Wonderfontein Spruit.
The report said that water in the river had absorbed polonium and lead. Barthel also noted in the study that there was no natural water in the whole area that was safe for use by humans, animals or plants.
However, Water Affairs and Forestry Minister Lindiwe Hendricks said in a written response to a question posed in parliament that none of the 47 samples from the Wonderfontein Spruit exceeded the NNR regulatory limit for public exposure. "The use of this water is therefore safe for drinking purposes, but it should be borne in mind that the water is raw or untreated river water that has not been treated to potable drinking water standards."
This assurance came despite her acknowledgement, in the same response, that "Elevated levels of radioactive contamination have been detected in the sediments of dams and weirs along the river. This may pose potential problems should it be ingested by live-stock churning up the sediments."
The chief executive of the NNR, Maurice Magugumela, has made an effort to quell public fears over this situation, saying that the poisoned water and sediments posed "no cause for concern."
In addition, the city council of Potchefstroom has gone to great lengths to assure its residents that the city’s drinking water is safe. Potchefstroom sources much of its water from the Boskop dam which is partly fed by the Wonderfontein Spruit.
"Treated water from the Boskop and Potchefstroom dams are of high quality especially regarding its heavy metal and uranium content," said mayoral spokesman Kaizer Mohau, in a statement.
There is no reason to doubt Mohau’s statement, which must certainly comfort city residents who drink tap water.
But it will do little for the estimated 150,000 people living in impoverished settlements along the Wonderfontein Spruit’s banks. They may have no choice but to drink untreated water from the river.
Acid mine drainage
Gold mines are also finding themselves in the dock over acid mine drainage, another means by which heavy metals are being released into the environment.
Mining operations expose heavy metals and sulphur compounds that have been locked away in the ground. Rising ground water then leaches these compounds out of the exposed earth, resulting in acid mine drainage that can continue to pollute the environment decades after mines have been closed down.
Water coming out of the disused mine in Randfontein could not simply be channelled into the nearest river because it was far too acidic and could have had serious consequences for the environment.
As an emergency measure, Harmony fed the water into Robinson Lake, at that time a popular recreational area where fishing was a favourite pastime. Today the lake has very high levels of uranium and a pH level of 2.2, which makes it as acidic as lemon juice and completely incapable of sustaining any life forms.
The NNR measured in the water a uranium concentration of 16 milligrammes per litre, obliging it to declare Robinson Lake a radiation area.
Here is the full article.