Acid mine drainage amd is generated under environmental conditions when sulfide minerals are exposed to oxygen, water, and acidophilic microorganisms. The orange coloration is due to the iron fe that has been mobilized by the sulfur oxidation process, which causes acid mine drainage to occur. Although acid mine drainage is the most common impact of mining on water quality, the variety of mineral geology is such that there is no singlecharacteristic mine water. Acid mine drainage amd, a waste from mining sites is highly acidic, rich source of sulfate and heavy metals. Amd is a major pollutant resulting in enhanced acidity of water bodies wherever it exists 7.
However, acid mine drainage eventually leaves its mark. Acid mine drainage research acid mine drainage amd has been the subject of intensive research since the 1960s. Wildeman billings symposium asmr annual meeting assessing the toxicity potential of mine waste piles workshop june 1, 2003 u. Mine drainage is formed when pyrite an iron sulfide is exposed and reacts with air and water to form sulfuric acid and dissolved iron. This is a natural chemical reaction which can proceed when minerals are exposed to air and water. Mineralogical transformations controlling acid mine. Research efforts have proceeded recently through the acid drainage technology initiative. In examining this table, it is important to note that diffusion of oxygen into water is slow and, therefore, oxidation of iron sulfide is inhibited until the water level drops, which can occur periodically or seasonally in some cases. The chemicals allow copper minerals to rise to the top and stick to. Acid mine drainage prevention and control options 601 prediction of performance the performance of the designed or selected options compared to the adopted standards is predicted by applying appropriate engineering techniques e. A study of environmental assessment of acid mine drainage. Conventional technologies for treatment of amd include various physicochemical methods, which involve excessive use of chemicals and capital. Some australian work using 18 o in near isotopically pure o 2 and h 2 o has identified the general direction of the reaction path. Acid mine drainage solutions for the mineral industry.
Environmental impact and remediation of acid mine drainage. Amd comes mainly from abandoned coal mines and currently active mining. Article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. As a result, the water becomes very acidic and damages downstream aquatic ecosystems. Supergene alteration of the sulphide ore and the mine waste leads to the formation of efflorescence and generation of acid mine drainage amd filling the pitlakes. Handson experiments to test for acid mine drainage dr.
The first measurement typically looks at acidity, which is. In a nutshell, acid mine drainage is a form of water pollution that happens when rain, runoff, or streams come in contact with rock that is rich in sulfur. Chemical extractions, xray diffraction xrd, scanning 40 electron microscopy sem, and fourier transform infrared spectroscopy ftir were. An introduction to acid mine drainage wv department of. January 1996 acid mine drainage is a common problem in many parts of the country, originating from hardrock mines, strip mines or tailing piles. Pdf biogeochemistry of acid mine drainage and a method. The acid runoff further dissolves heavy metals such as copper, lead, and mercury into groundwater or. Pdf acid mine drainage treatment with chemicals jeff. Mines should be able to use human rights rhetoric and additional contextual analysis to better understand how social impact issues can evolve into potential human rights violations. Acid mine drainage environmental notes on mining, updated september 2009 pyrite fes2 is commonly associated with coal and metal ore deposits. Acid mine drainage prediction compares acid rock drainage factors of waste rock piles and tailings impoundments. The microbiology of acid mine drainage by jim taylor, p. The life cycle of acid mine drainage copper ore from arizona concentrating ground up rock is mixed with water, air bubbles and small amounts of chemicals.
Major impact areas are rivers, lakes, estuaries and coastal waters, although amd affects different aquatic ecosystems in different ways. Inap exists to fill the need for an international body which mobilizes acid drainage. Sources of nonpoint source pollution acid mine drainage amd is currently the main pollutant of surface water in the midatlantic region. The chemistry of oxidation of pyrites, the production of. Generation of asrich acid mine drainage, natural attenuation processes and solutions for passive in situ remediation. Pdf a bacterium, thiobacillus ferrooxidans, is of prime importance in the formation of acid drainage from pyritic material. Recovery of rare earth elements rees from coal mine. The controlling parameters are defined by the physics of the site.
There is actually a complex series of reactions and side reactions, but the net equation is often written according to equation 1. Amd is caused when water flows over or through sulfurbearing materials forming solutions of net acidity. Arsenic geochemistry of acid mine drainage springerlink. Hardness is the concentration of divalent cations e. When the acid forming minerals do not contain significant quantities of iron, the acidic waters do. Some or all of this iron can precipitate to form the red, orange, or yellow sediments in the bottom of streams containing mine drainage. Although hightech analytical methods have been highlighted for mineral characterization and quantification, simple testing methods are still practical ways to perform in a field laboratory in mines.
Mining, waste ore burden, tailings, and exposure of abandoned mines to the environment promote amd. These frame the predicted metal criterion sum ccus 1, showing mean and range of. The acid mine drainage may also contain high amounts of co2 which forms carbonic acid and further depresses the ph. Waterquality criteria for some metals are hardnessdependent.
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. Ard is often mislabelled amd or acid mine drainage too. Acid mine drainage amd is a major environmental hazard of 20th century mining practice. So, to better understand amd and ard, lets begin by defining some terms like ph the standard measure of acidity. It affects aquatic ecosystems by a number of direct and indirect pathways. Because the chemistry of water samples can rapidly change if removed from the mine, many mine drainage measurements are made in the field. Acid mine drainage amd, which is caused by the biological oxidation of sulfidic materials, frequently contains arsenic in the form of arsenite, asiii, andor arsenate, asv, along with much higher concentrations of dissolved iron. This laboratory project uses the context of acid mine drainage to teach concepts important to analytical chemistry and quantitative analysis.
Work carried out at the abandoned copper cu and sulphur s mine at avoca south east ireland has shown acid mine drainage amd to be a multifactor pollutant. Treating acid mine drainage from abandoned mines in. This results primarily from the oxidative breakdown of transition metal sulfides, especially pyrite fes 2. Most discussions on acid mine drainage refer to the physical process of oxidation while the role of microorganisms is left unnoticed. Citations are the number of other articles citing this article, calculated by crossref and updated daily. Paul ziemkiewicz, director, wv water research institute. Case study of acid mine drainage amd and remediation. 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.
Aqueous chemistry, coupled with discharge volume can, thus, estimate the annual production of tree, amd sludge and the grade of amd sludge as a process feedstock. Introduction the mining of coal deposits and metal ores often results in a phenomenon called acid mine drainage amd. Characterization of mine waste rocks and prediction of acid mine drainage amd play an important role in preventing amd. Acid mine drainage project lab chemistry libretexts. Treating acid mine drainage from abandoned mines in remote areas john j. Progression of community reassembly responses with acid mine drainage recovery. Sulphate concentrations range from 4,600 to 4,850 mgl and from 35,900 to 38,500 mgl for the mathiatis and sha mines, respectively. We also acknowledge previous national science foundation support under grant numbers 1246120, 1525057. Acid mine drainage amd is typically characterized by low ph and high dissolved iron. Western pennsylvania was once a great coal mining region.
Acid rock drainage as a concern and part of all metals and mining operations. You can see from equation 1 that in order for these reactions to happen, the pyrite must be exposed to both air and mining is one of south africas most important industries, but it comes with a cost. Inap is an organization of international mining companies dedicated to reducing liabilities associated with sulphide mine materials. Acid mine drainage the center for rural pennsylvania. Acid mine drainage amd is a problem occurring across the. The remnants of this industry are still with us in the form of abandoned mines that underlay a great portion of the land on which we live, and in the drainage of acidic waters from the mines into our streams and rivers. Fundamentals of minedrainage formation and chemistry kathleen s. Acid mine drainage amd forms when sulfide m inerals are exposed to oxidizing conditions in coal and metal mining, highway construction, and other largescale excavations. Characterization of mine waste and acid mine drainage. Mine drainage chemistry reduce the impacts and engineering costs of poor quality mine drainage, such as acid mine drainage, through a comprehensive understanding of your site chemistry managing drainage water quality is a critical concern for all mining and nonmining rock handling operations. Acid mine drainage an overview sciencedirect topics. These metrics are regularly updated to reflect usage leading up to the last few days. Proc, difpolmine conf, le corum, montpellier, france, pp 17 evangelou vp 1998 pyrite chemistry. Steve oravetz program leader usda forest service technology and development program missoula, montana 7e72g71 acid mine drainage study october 1998 united states department of.
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. The term mine impacted water is used because it is more inclusive than terms such as acid mine drainage amd or acid rock drainage. 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 boat of knowledge ohio university.
Acid drainage from an abandoned coal mine has impacted this southwestern virginia stream. Fundamentals of minedrainage formation and chemistry. Acid mine drainage overview acid rock drainage ard is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide fes2. There are four chemical reactions that represent the chemistry of pyrite weathering to form acid mine drainage. Department of the interior colorado school of mines u. Biogeo chemistry of acid mine drainage and a method to control. Acidmine drainage abatement project in clarion county a report by andrew m. Recovery of rare earth elements rees from coal mine drainage dr. The mining of coal deposits and metal ores often results in a phenomenon called acid mine drainage amd. Mcsurdy department of energy pittsburgh research center p. Its oxidation occurs spontaneously in nature, causing environmental problems like acid mine drainage amd and mine. The international network for acid prevention inap is an industry group created to help meet the challenge of acid drainage.
363 1437 19 670 349 270 695 162 1342 425 1049 262 634 722 742 446 1138 1492 665 232 1180 41 1591 679 559 843 191 603 314 1343 505 1274 387 1355 379 272 839 607 333 1106 1461 245 459 153