To appreciate the impact of amd on south africa, it is therefore necessary to. Acid mine drainage amd is typically characterized by low ph and high dissolved iron. Feb 25, 2011 acid mine drainage amd occurs when old mine shafts and tunnels fill up, leading to underground water oxidising with the sulphide mineral iron pyrite, otherwise known as fools gold. Joining abn to discuss the impact it is having in south africa. This article is from the south african mining delegation seminar. Water flowing through active or abandoned mine sites can become polluted by the material being mined 1. Metesh hydrogeologist terrie jarrell project leader steve oravetz program leader usda forest service technology and development program missoula, montana 7e72g71 acid mine drainage study october 1998 united states department of. Actually, it has been described as the single most dangerous threat to south africas environment, after climate change. Acid mine drainage, acid and metalliferous drainage amd, or acid rock drainage ard is the outflow of acidic water from metal mines or coal mines acid rock drainage occurs naturally within some environments as part of the rock weathering process but is exacerbated by largescale earth disturbances characteristic of mining and other large construction activities, usually within rocks. With acid mine drainage amd threatening some of south africa s major cities, waterways and industries, south african technology providers are getting on the solutions bandwagon in the hopes of providing a novel approach to cleaning up an overwhelming mass of polluted water. Residents left in dark over acid mine drainage treatment. The impact of acid mine drainage in south africa south. Amd comes mainly from abandoned coal mines and currently active mining. Management and mitigation of acid mine drainage in south africa.
Acid mine drainage amd is a major problem all over the world, especially where coal and gold mine activities are common. This introduction of water is the initial step in most acid rock drainage situations. Acid mine drainage prevention and control options nural kuyucak golder associates ltd. Sulfuric acid is produced when water interacts with sulfurbearing materials in. The regulation of acid mine drainage in south africa. Could this be the key to solving sas acid mine drainage. Pdf the impact of acid mine drainage in south africa. The purpose of the longterm solution is to further treat the water by removing the sulphates and creating water for commercial use as.
Acid mine drainage consulting engineers south africa. Treated water running into a lake at a acid mine drainage plant near krugersdorp. In coalmining areas, the most common of these minerals is iron pyrite fes 2. Variables affecting the impact of acid mine drainage. The plan comes half a decade after acidic water from mine works. There are four chemical reactions that represent the chemistry of pyrite weathering to form acid mine drainage. Several mines in the witbank coalfield in south africa are affected by acid mine drainage. Amd causes severe environmental impacts, particularly on soil.
Acid mine drainage mines built as early as the 1800s were developed in a manner which utilized gravity drainage, to avoid excessive water accumulation in the mines as a result, water polluted by acid, iron, sulfur and aluminum drained away from the mines and into streams results of acid mine drainage. The purpose of the longterm solution is to further treat the water by removing the sulphates and creating water for commercial use as either industrial or potab. South africas acid mine water pollution risks lives. The mining companies and government have until about 2012 to control acid mine drainage before the toxic water under central johannesburg reaches an environmentally critical level. Rivers and lakes in arizona, patagonia, guangdong china, ontario, papua new guinea, and at rio tinto in spain, to name just a few, have all been polluted by acid mine drainage. In south africa the maximum limit is 400mg per litre. Acid mine drainage arising from gold mining activity in johannesburg, south africa, and environs. Amd comes mainly from abandoned coal mines and currently. This springerbrief focuses on acid mine drainage amd in the three basins in the witwatersrand, south africa. O c c a s i o n a l p a p e r researched and written for the gcro by kerry bobbins may 2015. Water and sanitation, dbsa amd and its adverse impacts put simply, acid mine drainage amd is acidic water that forms when water reacts with minerals voided by mining, which are then exposed to. Uranium pollution of south african streams an overview of the situation in gold mining areas of the witwatersrand.
Water flowing through active or abandoned mine sites can become polluted by the material being mined1. Acid mine drainage at a coal mine in the eastern transvaal. Recent news reports on acid mine drainage in gauteng have given wildly conflicting views from being the single most significant threat to south africas environment2. Earthlife africa, johannesburg branch 2009b acid mine drainage on the witwatersrand amd fact sheet 2, johannesburg, 16 august. Acid mine water drainage debating a sustainable solution.
South africas gauteng province holds some of the biggest gold deposits on earth, and extraction processes has left drains of acid mine drainage amd which results from the outflow of acidic. Impact of acid mine drainage on water resources in south africa have dropped significantly, showing that the water that was being pumped from the central basin was contaminating the spruit. Treatment of acid mine drainage using magnesium hydroxide. The south african government and nongovernmental organizations response to amd is assessed, as well the socioeconomic and developmental effects of amd. This has led to a deterioration in the water quality in many surface streams. Treating acid mine drainage from abandoned mines in remote areas john j. It serves to stand that the longer the problem goes untreated, the more costly and insurmountable the problem becomes. Mine in colorado, and the brohm mine in south dakota. Furthermore, acid mine drainage amd, pesticides from agricultural practices, unmonitored sewerage systems, domestic water usage like washing clothes on the river and dumping waste in water sources in some areas of the country, and salinization from the weathering of minerals all pollute water 42, 52, 53. Mining is a key contributor to south africa s economic development but its effect on the environment could spell disaster.
Water and sanitation, dbsa amd and its adverse impacts put simply, acid mine drainage amd is acidic water that forms when water reacts with minerals voided by mining, which are then exposed to air. Africa a phenomenologicalstudy on the degree of alignment between stakeholders concerning a sustainable solution to acid mine drainage. Dec 10, 2010 in response to the millions of litres of acid mine drainage already flooding or threatening to flood south africas streams, rivers, cities, and towns, a variety of solutions have been proposed. Acid mine water drainage debating a sustainable solution to a. Case study acid mine drainage south africa earthwise. Not all of south africa s mineral deposits are afflicted by acid production. Tailings piles or ponds, mine waste rock dumps, and coal spoils are also an important source of acid mine drainage. Our mine water treatment technologies are tailored for industrial use. Sulfuric acid is produced when water interacts with sulfurbearing materials in the presence of oxygen and common bacteria1. The potential utilisation of indigenous south african grasses for acid. Acid mine drainage amd has received considerable coverage in the media of late and.
The acid mine drainage solution bandwagon africas best read. This acid leaches out metals in the rock, which can enter nearby. Impact of acid mine drainage in south africa youtube. Acid mine drainage acid drainage occurs when minerals containing reduced forms of sulfur s oxidize via exposure to oxygen and water during earth disturbances figure 1. In 2006, south africa was the largest producer of gold, and the fourth largest producer of coal, in the world usher and vermuelen 2006.
In the eastern united states alone, amd from coal mines has adversely impacted fisheries associated with over,000 kilometers 8,000 miles of streams in pennsylvania, west virginia, ohio, and maryland. Acid mine drainage amd is currently the main pollutant of surface water in the midatlantic region. The longterm solution for gautengs acid mine drainage problem brought with it a source for clean water, but at a big cost. Acid mine drainage amd is the flow, or seepage, of polluted water from old mining areas. Input for mineral beneficiation in africa book october 2016 with 180 reads how we measure reads. The formation of acid mine drainage and the contaminants associated with it have been described as the largest environmental problem facing the u. Acid mine drainage solutions for the mineral industry.
Government and mining companies need to take responsibility now, taking extensive measures to prevent any further damage and to safeguard the local population. Pdf management and mitigation of acid mine drainage in. Law and governance perspectives l feris lj kotze acid drainage is one of the most serious and potentially enduring environmental problems for the mining industry. Jun 17, 2016 what is acid mine drainage amd, why is it such a serious threat to south africa and more importantly why has been it been silenced and kept under wraps by the mining industry and south african government for so long. The problem and the cleanup acid mine drainage is a global problem. Keywords acid mine drainage amd, mining industry, south africa, the united states, historical analysis, socioeconomic conditions. What can be done to prevent or clean up acid mine drainage. The gold mining industry in south africa principally the witwatersrand goldfield is in decline, but the postclosure decant of amd is an enormous threat, and this could become worse if remedial activities are delayed or not implemented. Water supplies around the world are becoming increasingly scarce due to rising global populations, increasing industrial processes, pollution and inequitable water distribution.
Acid mine water drainage debating a sustainable solution to a serious issue. Acid mine drainage amd is an acidic, sulfurrich, metallic wastewater, originating from mine discharge of both operational and abandoned mines 1. Acid mine drainage and human rights south african human. Amd is caused when water flows over or through sulfurbearing materials forming solutions of net acidity. South africa s gauteng province holds some of the biggest gold deposits on earth, and extraction processes has left drains of acid mine drainage amd which results from the outflow of acidic. This springerbrief focuses on acid mine drainage amd in the three basins in the.
Marius keet, from south africa s water and sanitation department has said that acid mine drainage is south africa s greatest environmental challenge, while acknowledging that coal will remain. Finding solutions for south africas coalfired water and. Acid mine drainage an overview sciencedirect topics. Pdf impact of acid mine drainage on water resources in. Acid mine drainage is not a new issue, merely one that has been conveniently silenced by the mining houses and south african government for decades. Mine water and wastewater treatment solutions from veolia water technologies south africa veolia help mining companies in south africa and africa reduce their effects on the environment with economical mine process water and wastewater treatment technologies.
The effect of mining on the environment includes the release of many chemical contaminants into water resources, which can cause environmental damage and threaten the health and safety of nearby communities long after mine closure. Acid mine drainage in johannesburg greenpeace africa. This may be the biggest challenge of all the unknown. This paper aims to unpack the size of the problem and the availability of the solutions to deal with the issue facing south africa s water systems. Acid mine drainage overview acid rock drainage ard is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide fes2. The impact of acid mine drainage in south africa article pdf available in south african journal of science 10756. Ewart, timothy ian 201112 thesis mphilstellenbosch university, 2011. South africas acid mine water pollution risks lives africanews.
The acid mine drainage solution bandwagon the mail. When a mine is abandoned, the pumping ceases, and water floods the mine. After much investigation, the probable cause was determined. Acid mine drainage in the gauteng province of south africa. Acid mine drainage solution targeted at south african mining. Acid rock drainage and acid mine drainage acid rock drainage ard is a natural process in which sulfuric acid is produced when sulfides in rocksfor example, pyrite fes 2 are exposed to air and water. Amd is a legacy left behind by abandoned, derelict and defunct mines, and is a continuing byproduct of existing mining activities. Left unchecked, it can result in such longterm water quality impacts that it could well be this industrys most harmful legacy. South africas legislative framework for mine closure. Acid mine drainage in south africa development actors. South africa is facing the increasing challenge of acid mine drainage amd whose genesis is the country s mining history, which paid limited. The simplest treatment is neutralization and clarification. Finnish specialist in hydrometallurgical treatment technology global ecoprocess services oy epse launched a treatment for acid mine drainage amd in south africa in july, which it claims is a.
As amd is recognized as one of the more serious environmental problems in the mining industry, its causes, prediction and treatment have become the focus of a number of research initiatives commissioned by governments, the mining industry, universities and research establishments, with additional. Treating acid mine drainage from abandoned mines in. Jun 12, 20 for individual support on doing business in south africa, specific questions about market opportunities and to receive a full report, please contact juliet. Dbsa development bank of south africa dea department of environmental affairs. The acid mine drainage waste is characterized by red water. Witwatersrand gold occurs in layers of conglomerate rock. Timeline of key events and the development of solutions to address. R600 million per annum has been committed to creating a permanent solution to acid mine drainage that will also produce potable water.
Final words acid mine drainage issues in south africa. The key factor of acid mine drainage amd in the history. Pdf impact of acid mine drainage on water resources in south. This paper describes acid mine drainage amd generation and its associated technical issues. Using fes 2 as an example, amd for mation can be represented as follows.
Mine acid drainage mad is the runoff produced when water comes into contact with exposed rocks containing sulfurbearing minerals that react with water and air to form sulfuric acid, dissolved fe and al, and other chemical elements blowes et al. Acid mine drainage amd is arguably one of the most serious environmental concerns in south africa. This occurs in different ways in gold and coal mining. The witwatersrand basin, south africa, as a case study. These effluents require neutralisation and metal removal prior to release to public watercourses. Acid mine drainage in gauteng province, south africa mining in south africa and in gauteng province. A new solution to treat acid mine drainage amd, targeting the south african mining industry, was launched on july 5, in johannesburg, as a viable and cost effective solution to remove metals and. Hence, an initial investigation was carried out to determine the source of acid mine drainage pollution and the associated hydrogeological conditions. Acid mine drainage in the gauteng province of south africa core. The decanting of acid mine water in the gauteng cityregion. Greenpeace africa is deeply concerned by both the extent of the problems of acid mine drainage in the johannesburg region, and by the lack of action by the authorities and mining companies. Once amd is generated, it is difficult to control the process and the treatment also requires high cost aguiar et al.
Acid mine drainage issues in south africa godfrey mwiinga pr. The acidic water formed by this process can dissolve many metals in bioavailable. This occurs along outcrops or scree slopes where sulfidebearing rock is naturally weathered. Vws sa and stateowned minerals researcher mintek announced earlier in 2012 that they. By far the most common mine drainage problem is that of acid mine drainage amd. Thanks to the international veolia group, veolia water technologies south africa is able to supply a costcompetitive acid mine drainage treatment system that can reduce the impact of mining on the environment.
Acid mine drainage solution targeted at south african. Mathematical modelling in acid mine drainage geoffrey s simate abstract for over 50 years, acid mine drainage amd pollution has been recognised as an important and widespread societal problem. The acid mine drainage may also contain high amounts of co2 which forms carbonic acid and further depresses the ph. This is a natural chemical reaction which can proceed. The origin of acid mine drainage acid mine drainage also sometimes referred to as acid rock drainage is a wellunderstood process2 and arises primarily when the mineral pyrite fools gold or iron disulphide comes into contact with oxygenated water. Acid mine drainage in south africa has become a major concern for the countrys water infrastructure over recent years.
The chemical characteristics of acid mine drainage with particular reference to sources, distribution and remediation. It provides a background to amd and its impactsfrom a social science perspective. The acid water is believed to be currently about 600m below surface of johannesburg and surrounding areas, but is rising at an estimated rate of between 0. Acid mine drainage amd is a significant threat to the environment in south africa and needs to be remedied. Acid mine drainage effects, types, plants, marine, oxygen. Acid mine drainage amd in the gauteng cityregion gcr has been.
Another option is to dilute or flush the water using water from clean systems the eventual solution at carolina but this is a massive waste of a precious commodity in a dry. The department described its progress in dealing with the challenge of acid mine drainage amd, and confirmed that the shortterm solutions implemented at all three vall river system basins were operating well, with levels below environmentally critical levels. The pyrite undergoes oxidation in a twostage process, the. Acid mine drainage and its governance 10 in the gauteng cityregion o c c a s i o n a l p a p e r. Pretoria with the acid mine drainage amd shortterm solution close to a successful completion, water and sanitation minister nomvula mokonyane will on wednesday launch the amd longterm solution through the interministerial committee imc on amd, government in 2011 mandated the transcaledon tunnel authority tcta, a stateowned entity under the department of water and. South africa is a nation under stress when trying to meet water requirements. The south african government and nongovernmental organizations response to amd is assessed, as well the.
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