Acid water rescue plan for Johannesburg

LazyLion

King of de Jungle
Joined
Mar 17, 2005
Messages
104,835
http://www.timeslive.co.za/local/article645484.ece/Acid-water-rescue-plan

Acid water rescue plan - R218m pump to fix city's mega problem

The government has announced a multimillion-rand plan to drain the poisonous and acidic water out of Johannesburg's underground mines to prevent it from flooding and spilling into streets.

Although she couldn't provide details, Water Affairs Minister Buyelwa Sonjica said the plans included the building of a pump station next year to drain the water emanating from mines under the city.

In March, The Times reported warnings by scientists and geologists that should the levels of acid mine drainage be left unchecked, it would rise to the surface in two years and corrode the foundations of buildings and other infrastructure, damaging their structural integrity.

Water Affairs regional director Marius Keet said one of the options available to the department would be to locate the pump station at the East Rand Proprietary Mines in Boksburg, east of the city.

"Our estimate is that the pump will cost about R185-million. Water will be partially treated and discharged into the Klip River, which is a tributary of the Vaal River. It will take about one year to design and build the pump," he said.

Keet said acid mine drainage in the Johannesburg region, known as the Central Basin, was within 500m of the surface, and rising at a rate of 0.35m per day. "Something has to be done," he said.

He said the toxic water would become a crisis should it rise to about 150m from the surface.

Sonjica said: "Our immediate priority is to avert the crisis that will be upon us in 17 months. We have to install the pump. It has to happen within 17 months."

Sonjica also announced that the Cabinet had appointed an inter-ministerial committee to address acid mine drainage issues around Gauteng.

"We remain committed to ensuring that the rise in the water table under the Central Basin remains below critical levels, and that there are measures to deal with water already decanting in the Western Basin," Sonjica said.

The Western Basin includes mining areas between Krugersdorp and Randfontein, while the Central Basin stretches from Germiston to Roodepoort, through Johannesburg.

The inter-ministerial committee, Sonjica said, will report back to Cabinet within six weeks.

"Surely government will have to get funding to address issues in the short term," she said, adding that government needed about R218-million to deal with problematic mine water in the short-term.

It's been left way too late... but at least they are planning on doing something now. But what effect will this have on the river into which it is pumped?
 

Nothxkbi

Banned
Joined
Mar 19, 2010
Messages
4,529
Quite scary actually to think that thousands of kilometres of mine shafts are honecombed underneath such a vaste area and its filling up with water. My geography is a little hazy but doesn't it stretch all the way from Krugersdorp to Benoni?
 

genetic

Honorary Master
Joined
Apr 26, 2008
Messages
37,180
I'd love to know about the myriad of abandoned mine-shafts and tunnels underneath Johannesburg.

It'd make a great documentary for History Channels "Cities of the Underworld".

Back on topic... Glad they're taking action though.
 

The_Assimilator

Executive Member
Joined
Nov 7, 2005
Messages
5,923
But what effect will this have on the river into which it is pumped?

As long as the beautiful buildings of Johannesburg don't sink into a massive pool of acid, who cares about the environment? /sarcasm (Obviously., when they say the acid water will be "partially treated", they really mean "completely untreated".)

Also, why is this a government problem, as opposed to the mines' responsibility?
 

genetic

Honorary Master
Joined
Apr 26, 2008
Messages
37,180
As long as the beautiful buildings of Johannesburg don't sink into a massive pool of acid, who cares about the environment? /sarcasm (Obviously., when they say the acid water will be "partially treated", they really mean "completely untreated".)

Also, why is this a government problem, as opposed to the mines' responsibility?

Because most of those mines were shut down decades ago. It's not only caused by recent mining activity.
 
F

Fudzy

Guest
Also, why is this a government problem, as opposed to the mines' responsibility?

Was actually listening to an interesting talk on SAfm about this, the reason why they can't go after the mines is that a large percentage of the acid water is filling in mines that were abandoned decades ago, a lot of the mining company don't even exist anymore.
 

LazyLion

King of de Jungle
Joined
Mar 17, 2005
Messages
104,835
Quite scary actually to think that thousands of kilometres of mine shafts are honecombed underneath such a vaste area and its filling up with water. My geography is a little hazy but doesn't it stretch all the way from Krugersdorp to Benoni?

Yep! It is a massive underground network. Pity they couldn't have filled it in long ago.
 

The_Unbeliever

Honorary Master
Joined
Apr 19, 2005
Messages
103,196
just bottle it and sell it off as battery water.

problem solved :D

(not so simple though... hope they come up with an efficient solution, one which will not involve eishkom in a large way...)
 

LazyLion

King of de Jungle
Joined
Mar 17, 2005
Messages
104,835
What sort of acid is it?

"This study revealed that the ground water within the mining district is heavily contaminated and acidified as a result of oxidation of pyrite (FeS2) contained within mine tailings dumps, and has elevated concentrations of heavy metals. Where the water table is close to surface, the upper 20 cm of soil profiles are severely contaminated by heavy metals due to capillary rise and evaporation of the ground water. The polluted ground water is discharging into streams in the area and contributes up to 20% of stream discharge, causing a lowering of pH of the stream water. Much of the metal load is precipitated in the stream: Fe and Mn precipitate as a consequence of oxidation, while other heavy metals are being removed by co-precipitation. The oxidation of iron has created a redox buffer which controls the pH of the stream water. The rate of oxidation and of dilution is slow and the deleterious effect of the addition of contaminated water persists for more than 10 km beyond the source."

Source... http://www.sciencedirect.com/scienc...85635f6df2dafc6b900949edefaaa043&searchtype=a
 

Nothxkbi

Banned
Joined
Mar 19, 2010
Messages
4,529
This is only half the problem though. The mine dumps contain Cyanide which was used in mining many years ago. When its winter that dust gets blown everywhere (those from the East Rand know about this horrible problem), and when it rains all that poison goes into the water table and rivers.

Poor Joziburg really is in a mess.
 

Flanders

Honorary Master
Joined
Nov 20, 2003
Messages
13,827
Apparently it's also just a matter of time before places like the Sterkfontein cave system becomes contaminated. West rand is already in the dwang.
 

dlk001

Executive Member
Joined
Jul 29, 2005
Messages
7,336
It's been left way too late... but at least they are planning on doing something now. But what effect will this have on the river into which it is pumped?

Indeed its left too late. Unfortunately any discharge from wasterwater or AMD plants will result in some negative ecological impact in the receiving river system. The key is to match the design of the treatment works/plant to the specific receiving river environment. Also its important to monitor the process in both ends.

Unfortunately, this means tax payers will be paying for pumping/treating of this water for ever.
 
Top