Stream of acid, the Tweelopiespruit

http://www.earthlife.org.za/?p=1035

The Tweelopiespruit is a stream that flows through the Krugersdorp Game Reserve on the West Rand, near Johannesburg, South Africa. 

 

Tweelopiespruit flowing downstream of Hippo Dam, 8 May 2010 (photo Alistair Clacherty)

Acid mine water has been flowing into the Tweelopiespruit for years. The acid mine water contains high levels of sulphates and heavy metals, including radioactive uranium. The water sources of thousands of people downstream of the Tweelopiespruit are at risk.  In January 2010 the amount of acid mine water flowing into the stream increased dramatically. Millions of litres of acid mine water began to decant (overflow uncontrollably) from an old mine shaft into a wetland area that drains into the Tweelopiespruit.

Acid mine water, partially treated with lime, has been discharged directly into the Tweelopiespruit since about April 2010. Lime makes the metals fall out of the water and settle in the mud at the bottom of the stream and its dams. However, it appears that this treatment process is irregular and inadequately monitored (see http://www.earthlife.org.za/?p=989). The acidity of the water is not being controlled effectively (see below) and the water flowing out of the Krugersdorp Game Reserve is still toxic.

 The following photographs were taken on 8 May 2010. The iron in the water gives it the orange-red colour.  

The Tweelopiespruit, flowing under the road (R24) from the Rand Uranium property and into the Krugersdorp Game Reserve. (Photo Alistair Clacherty).  On 8 May 2010, the water sample taken from this part of the Tweelopiespruit had a pH of 2 – as acidic as lemon juice! In contrast, a stream a few km away with frogs and signs of a visiting otter, had a pH of 6.5.

Reading of pH2, water sample from Tweelopiespruit near R24, 8 May 2010 (Photo: Alistair Clacherty)

On 8 May 2010 the water sample from Hippo Dam had a pH of 4. The mud at the bottom of this dam is contaminated with heavy metals that have dropped out of the acid mine water as result of the lime treatment. 

No dissolved oxygen in water sample from Hippo Dam, 8 May 2010 (Note the red is the rubber bung in tube) (Photo: Alistair Clacherty)

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