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1.
Acid mine drainage （AMD） has been recognized as a major environmental pollution problem over past decades. This pollutant effluent is complex and is characterized by elevated concentrations of iron and sulfate, low pH, and high concentrations of a wide variety of metals depending on the host rock geology. Massive inadvertent discharges from acid mines have given rise to dramatic cases of ecological damage. These events indicate an improved understanding of the mechanism controlling metal transport to the river is important, since the aquatic ecology will be affected, to some degree, dependent on the phase （dissolved or particulate） in which the metal is transported. In this study, polluted water samples were collected along the Hengshi River near the Dabaoshan mine, Guangdong, China, in April 2005. The concentrations of dissolved Cu, Zn, Cd and Pb have been determined using ICP-MS and the chemical speciation of those metals in suspended particles was examined using BCR methods and SEM/EDX mineralogical analysis. Combining these two sets of data, the intention was to develop geochemical concepts, which explain the behavior of Cu, Zn, Cd and Pb in particle-water interactions of heavy metals in AMD. The results show that the dissolved heavy metals exhibited non-conservative behavior in the Hengshi River. The dissolved and particulate Cu, Zn, Cd and Pb have the similar spatial distribution, which decreased gradually along the river except in the lower reaches because of the absorption-desorption between dissolved and particulate phases. Although the metal concentrations in both phases were elevated, dissolved metals were dominant and had the maximum concentrations in the low pH region.  相似文献   

2.
Mine water inrush is one of the main hazards in coal mining industry. The mechanism and the processes are complex. Investigation of the spatiotemporal development of the hydrological process could lead to a better understanding of mine water inrush and effective countermeasures. For this reason, we investigated spatial and temporal characteristics (i.e., the changes of flow rate, groundwater level, and water quality) during a water inrush event in China, which had a flow rate of 730 m3/h at maximum and 300m3/h under a steady condition. The result shows that the water inrush developed in several stages. A mathematical model of the dynamic change between the water table and the inrush flow rate was constructed. Based on this model, we found the relationship of highly conductive flow channels between some observation boreholes and the water inrush point. In addition, the recharge velocity of the highly conductive flow channels and the equivalent mean flow velocity of the whole mine were determined. A comprehensive analysis of geological, hydrodynamic, and crustal stress conditions was conducted to study the development of the water channel near the F13 fault and the nonlinear process from seepage stage to inrush stage. The result reveals the water inrush is likely caused by activation of faults under combined influences of high crustal stress and high hydraulic pressure.  相似文献   

3.
Effluent from tailings impoundments of sulfide mine is an important environmental problem. The oxidation of sulfide minerals in tailings impoundments and consequent release of acid and contaminants, including heavy metals and arsenic, to tailings pore-water can last for decades to centuries. Pollution of water bodies including surface water and groundwater occurs when infiltration of precipitation is unhindered, bottom liners are absent and no drainage collection is installed. So there is a great need to develop reliable modeling techniques for characterizing geochemical interactions taking place within the tailings and predicting potential future environmental hazard which favor further prevention and remediation of the acidic mine drainage （AMD）. In this paper, a comprehensive dynamic model for tailings-water interaction was established on the basis of considering the coupling and feedback among many factors and processes such as sulfide oxidation, gangue dissolution, oxygen diffusion, water flow and mass transport,  相似文献   

4.
The Panzhihua iron mine, a famous V-Ti magnetite mine in our country, is composed of the Jianshan, Lanjiahuoshan and Zhujiabaobao ore areas. It has caused many ecological problems in the Panzhihua iron mine after nearly 40 years of mining, which has severe impact on safe mining and has brought huge economic losses. This paper begins with the environmental geological problems caused by unloading （mining） and loading （mine dump） that is then resulted from mining activities. The paper then analyses and studies the cause and development of every environmental geological problem as well as the formation of geological disasters （landslip, coast and landslide） from two aspects： geological disasters and environmental geological problems caused by mining activities. Meanwhile, the paper puts forward suggestions about prevention and management of mine. It is found that material unloading in the Panzhihua iron mine has made the originally stable geological body be less stable, and has formed much disastrous slope. The resulted geological disasters include landslip, landslip, etc. Material loading, i.e. mine dump, has caused a huge artificial loose stack piled up in valleys. The steep slopes can easily result in geological disasters, such as landslip, landslide, debris flow, etc. Till now, there have been over10 times geological disasters caused by material unloading, and over 20 times caused by material loading. The economic loss has been over 0.1 billion yuan RMB. It is also found that the major impact of mining on environment is the pollution of soil and water caused by heavy metals. Besides this, powder is also another source of pollution.  相似文献   

5.
《Applied Geochemistry》2000,15(9):1383-1397
Water pollution arising from base metal sulphide mines is problematic in many countries, yet the hydrogeology of the subsurface contaminant sources is rarely well-characterized. Drainage water pumped from an active F–Pb mine in northern England has unusual chemistry (alkaline with up to 40 mg.l−1 Zn) which profoundly impacts the ecology of the receiving watercourse. Detailed in-mine surveys of the quantity and quality of all ground water inflows to the mine were made. These revealed major, temporally persistent heterogeneities in ground water quality, with three broad types of water identified as being associated with distinct hydrostratigraphic units. Type I waters (associated with the Firestone Sill aquifer) are cool (<10°C), Ca–HCO3–SO4 waters, moderately mineralized (specific electrical conductance (SEC)≤410 μS.cm−1) with <4 mg.l−1 Zn. Type II waters (associated with the Great Limestone aquifer) are warmer (≈15°C), of Ca–SO4 facies, highly mineralized (SEC≤1500 μS.cm−1) with ≤40 mg.l−1 Zn. Type III waters (in the deepest workings) are tepid (>18°C), of Ca–HCO3–SO4 facies, intermediately mineralized (SEC≤900 μS.cm−1) with ≤13 mg.l−1 Zn, and with significant Fe (≤12 mg.l−1) and Pb (≤8 mg/l). Monotonic increases in temperature and Cl− concentration with depth contrast with peaks in total mineralization, SO4 and Zn at medium depth (in Type II waters). Sulphate, Pb and Zn are apparently sourced via oxidation of galena and sphalerite, which would release each metal in stoichiometric equality with SO4. However, molal SO4 concentrations typically exceed those of Pb and Zn by 2–3 orders of magnitude, which mineral equilibria suggest is due to precipitation of carbonate “sinks” for these metals. Contaminant loading budgets demonstrate that, although Type II waters amount to only 25% of the total ground water inflow to the mine, they account for almost 60% of the total Zn loading. This observation has important management implications for both the operational and post-abandonment phases of the mine life cycle.  相似文献   

6.
The Podljubelj mercury mine lies in the NW part of Slovenia. The ore is of hydrothermal-vein type. The ore deposit was exploited between the years 1557 and 1902. Total production of the mine was 110000 tons of ore （360 tons of Hg）. A smelter located close to the mine had been in operation since 1855. The waste material from the mine and the smelter was dumped in close vicinity of the mine. Total quantity of the waste has been estimated at 170000 tons. In order to establish environmental impacts, soil and stream sediment samples were investigated. Soil samples were collected at two different depths （horizons A and B） in a 100 m grid within an 88 ha area. In the vast area also 11 samples of stream sediments were considered. Heavy metals were determined by means of cold vapor atomic absorption spectrometry CV-AAS after aqua regia digestion. Based on the chemical analyses of samples, the estimated mercury mean for soils is 3.67 mg/kg （0.35-244 mg/kg） for horizon A and 1.39 mg/kg （0.17-71.7 mg/kg） for horizon B. The estimated mercury mean for stream sediments is 0.64 mg/kg （0.065-1.36 mg/kg）. The concentrations of mercury in soils generally decrease with depth and distance from the mine. The highest content of Hg was determined in a sample taken in the immediate vicinity of the smelter （719 mg/kg）. The results have shown that on the 9 ha of the study area, the contents of Hg in soils exceeded the officially set limit value for soils （10 mg/kg）. High contents of Hg in soil around the abandoned smelter are a consequence of former atmospheric emissions and technological losses. High contents of Hg were also found in the mine and smelter waste dump. At the edges of the study area and in the samples of stream sediments, Hg concentrations are low.  相似文献   

7.
In this work we have studied the geochemistry of stream waters arising from waste dumps at the Peña de Hierro mine (Iberian Pyrite Belt, SW Spain), and we have correlated them with the mineralogical and geochemical characteristics of the wastes to asses the source and factors affecting the release of trace elements. The mineralogical composition and geochemistry of 58 borehole samples of waste dumps were studied in the <2 mm fraction. Twenty-eight water samples collected in winter and summer from streams emerging from the waste dumps were analysed for pH, Eh, conductivity, temperature, sulphates and major and trace elements. The leachates from pyrite-rich volcanic tuffs produced very acidic waters, usually with pHs below 2 and reaching values as low as 0.7. The partial dissolution of gossan, which is mainly composed of Fe oxy-hydroxides and is rich in trace elements, released high concentrations of Fetot (up to 33 g/L), As (up to 72), Mo (up to 11 mg/L). On the other hand Cd, Zn and Pb reached up to 0.85, 142 and 0.42 mg/L, respectively, in the stream arising from roasted pyrite ashes and other pyritic wastes. Several elements such as Al, Fe, As, Co, Cu and Mo were strongly correlated with the pH, but Cd and Zn were not correlated under such acidic conditions. The precipitation of jarosite seems to be an important factor in the retention of Pb. The mobility sequence of trace elements shows that Co, Zn and Cd were among the most mobile elements; Cu, As and Mo had intermediate mobility, and Pb was the most immobile. This work shows that uncontrolled waste dumping increases the pollution potential, and a selective management could reduce the release of trace elements into stream waters and mitigate the contamination.  相似文献   

8.
Acid–base accounting (ABA) is a static test used to evaluate pre-mining drainage quality of ores with interpretations based on a reference 3-data point model. The method is often complemented with a kinetic test to ensure certainty of results. The challenges associated with both methods compel companies to rely on only the ABA test, thereby compromising on the long-term drainage quality. This paper validates a proposed 4-data point model that was used to establish a 20% increase in the alkaline amendment of ores at the AngloGold Ashanti Obuasi Mine in Ghana. The validation was done using model limits, the robustness of coefficient of determination and model factor sequence variation. Acidification trends and mineralogical data evaluation of tailings were used to characterise pH buffer trends in mine drainage. The modified 4-data point model, which incorporates a vital kinetic test factor into the ABA model, provides a criterion for the adjustment of carbonate amendment value to improve acid neutralisation in the drainage; this would reduce (1) cost of experimentation, (2) turnaround time for analyses, (3) complexities associated with both test methods. From the XRD data, alunite and goethite are present in tailings to provide sustained pH buffering in drainage beyond the scope of the modified model, while the characterised pH buffer trend could be used for monitoring drainage quality.  相似文献   

9.
《中国地球化学学报》2006,25(B08):33-33
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10.
Catastrophic flow failures have occurred with alarming frequency in mine tailings dams and dumps of discards and other mine waste. In recent years, catastrophic flow failures have also occurred in dumps of municipal solid waste and even in what were intended to be carefully controlled and well-engineered landfills. Apart from the environmental devastation caused by these flows, they are also dangerous to human life and society. Examples include the Buffalo Creek disaster in the USA in 1972 (Vick, Planning, Design and Analysis of Tailings Dams, Wiley, 1983) that killed 118 people, made 4000 homeless and destroyed 50 million US dollars worth of property and facilities. The flow slide that occurred in the Umraniye– Hekimbasi refuse dump in Turkey in 1993 (Kocasoy and Curi, Waste Management and Research, 13, 1995, 305) killed 39 people, destroying their homes in the process. This paper will briefly review some of the more notable flow slides in waste materials, analyzing conditions necessary for a flow failure to occur and pointing to ways of preventing this type of failure by a combination of sound design and operating procedures.  相似文献   

11.
In the bed of the Rudnaja River( Primorye, Russia) the influents of the polymetallic mine tailings and processing factories affected the river water chemistry, especially heavy metal concentrations. Decreasing of production in the last 10–15 years was re…  相似文献   

12.
Several occurrences of gold-bearing quartz veins are situated along the east–northeast-trending Barramiya–Um Salatit ophiolitic belt in the central Eastern Desert of Egypt. In the Barramiya mine, gold mineralization within carbonaceous, listvenized serpentinite and adjacent to post-tectonic granite stocks points toward a significant role of listvenitization in the ore genesis. The mineralization is related to quartz and quartz–carbonate lodes in silicified/carbonatized wallrocks. Ore minerals, disseminated in the quartz veins and adjacent wallrocks are mainly arsenopyrite, pyrite and trace amounts of chalcopyrite, sphalerite, tetrahedrite, pyrrhotite, galena, gersdorffite and gold. Partial to complete replacement of arsenopyrite by pyrite and/or marcasite is common. Other secondary phases include covellite and goethite. Native gold and gold–silver alloy occur as tiny grains along micro-fractures in the quartz veins. However, the bulk mineralization can be attributed to auriferous arsenopyrite and arsenic-bearing pyrite (with hundreds of ppms of refractory Au), as evident by electron microprobe and LA-ICP-MS analyses.The mineralized quartz veins are characterized by abundant carbonic (CO2 ± CH4 ± H2O) and aqueous-carbonic (H2O–NaCl–CO2 ± CH4) inclusions along intragranular trails, whereas aqueous inclusions (H2O–NaCl ± CO2) are common in secondary sites. Based on the fluid inclusions data combined with thermometry of the auriferous arsenopyrite, the pressure–temperature conditions of the Barramiya gold mineralization range from 1.3 to 2.4 kbar at 325–370 °C, consistent with mesothermal conditions. Based on the measured δ34S values of pyrite and arsenopyrite intimately associated with gold, the calculated δ34SΣs values suggest that circulating magmatic, dilute aqueous-carbonic fluids leached gold and isotopically light sulfur from the ophiolitic sequence. As the ore fluids infiltrated into the sheared listvenite rocks, a sharp decrease in the fluid fO2 via interaction with the carbonaceous wallrocks triggered gold deposition in structurally favorable sites.  相似文献   

13.
A study of soils and four flourish plants in the heavy metal polluted area by lead/zinc mine in northwestem Guizhou Province. In this study four plants were collected, the species were： Sambucus Chinensis Linn, lxeris gracilis （DC.） stebb, Buddlej daxidii Franch.ex.sinarum lmp. and Senecio scandens. The fractions of heavy metals in the soil were distinguished by the short sequential extraction procedure （I. Maiz, 1997）, the available fractions and residual fractions of heavy metals in the soil could be separated. The plant digestion was effected by means of the microwave digest system （Durali Mendil, 2004）. In each step Pb, Zn and Cd were analyzed by FAAS. This study analyzed the heavy metals （Pb, Zn, Cd） contents of the soil and plant. It is found that the contents in the plant increased linearly with heavy metal concentrations in soil. The concentrations of Pb, Zn, Cd in the four plants follow the order of Zn〉Pb〉Cd. Sambucus Chinensis Linn and lxeris gracilis （DC.） stebb were proved to have good metal-enrichment and transport ability for heavy metals in the soil.  相似文献   

14.
Acid mine drainage (AMD) pollution is considered to be the most serious water pollution problem in mining areas. AMD containing iron sulfates and other components can affect the receiving water bodies. Pyrite oxidation and AMD generation can be considered as important processes that may take place in the wastes produced by coal mining and coal washing operations in the Golestan province (northeast Iran). The study area is characterized by appropriate atmospheric conditions that favor pyrite oxidation and the presence of a large amount of water bodies. This study attempts to consider pyrite oxidation and AMD generation in the Azad shahr–Ramian region. The impact of AMD on the quality of the surface water bodies was investigated by taking samples and analyzing them for hydro-geochemical parameters. Stiff and Piper diagrams were used to represent chemical analyses of water samples. The coal samples taken from different depths at four points on two different coal waste dumps were analyzed to find the fraction of pyrite that remained in the waste particles to investigate the pyrite oxidation process. A computational fluid dynamic package called PHOENICS was used to model pyrite oxidation process numerically. The results obtained from the geochemical analyses of water and coal samples and numerical simulation show pyrite oxidation and acid generation in the region. However, the presence of carbonate rocks raised the pH of the water samples. The drainages of the Razi mine may be recognized as natural alkaline mine drainages.  相似文献   

15.
The right to food is increasingly evoked by a range of actors, but there is not sufficient critical analysis of distinct interpretations of what this right means in practice. Through examination of a mineral extraction project with agricultural implications, this article explores diverse human rights narratives and illuminates associated corporate efforts to minimize recognition of food as a fundamental right. A British mining company proposes the Phulbari open pit coal mine in an agriculturally important region of Bangladesh. Highly contested by affected populations, clashes in 2006 between the police and protestors turned deadly in the area. In February 2012, a group of UN Special Rapporteurs cautioned the Government of Bangladesh regarding human rights violations associated with the planned mine. They warned that the project would displace hundreds of thousands of people, while destroying fertile agricultural land. In contrast, an ongoing publicity campaign by the corporation attempts to promote their intervention as a positive step, fully compliant with international human rights and corporate social responsibility standards. Taking this case as an exemplar, the article illuminates the pursuit of mining profit and the distinct use of human rights narratives by corporations and UN Special Rapporteurs. These diverse actors represent the layering of voices weighing in on mineral extraction and associated right to food concerns. Collectively, these layered narratives represent a new terrain for the promotion and contestation of mining and highlight the need to scrutinize mining practices in light of social responsibility and human rights claims being voluntary and self-regulated.  相似文献   

16.
In this study, the probabilistic key block analysis was applied to evaluate the stability of a mine ventilation shaft developed in a rock mass of granite. The key blocks were identified based on the block theory. The variations of discontinuity orientations were fitted with the Beta distribution and taken into consideration. The key block forming probabilities were analyzed. For simplification of calculations the first-order second-moment (FOSM) approximation was employed for probability estimation. With the considerations of the rock properties as random variables and applications of several statistical analysis tools, the key block failure probabilities, the probabilistic distribution of safety factors, and the probabilistic distribution of potential maximum key block volumes were analyzed. The analysis indicated that although the safety factor calculated based on the mean values of the variables was above 1.0 for the stability of the most critical key block, the block had a considerable probability of failure with a significant rock volume due to variations in discontinuity orientations and rock properties. Without promptly applying supports to the rock excavation, the shaft had a significant likelihood of failure.  相似文献   

17.
《中国地球化学学报》2006,25(B08):32-33
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18.
Local water contamination by arsenic can be caused by gold mining activities as in Snow Lake, Manitoba. This project was to f＇md the source （s） and pathways of the arsenic contamination and describe arsenic attenuation in ground and surface water. The project was initiated because arsenic concentrations average 16.0 mg/L in one groundwater monitoring well （MW17）. One potential source of arsenic is the 50 year-old Arsenopyrite Residue Stockpile （ARS）, 100 m upgrade of MW17. Between 1948 and 1959, 250000 tons of cyanide treated, arsenopyrite concentrate were stored in a waste rock impoundment, which was left open until 2000 when it was capped with layers of waste rock, clay and silt to minimize water infiltration and the oxidative release of arsenic.  相似文献   

19.
As one of the largest copper–molybdenum (Cu–Mo) mines in the world, the Erdenet Mine in Mongolia has been active since 1978 and is expected to continue operations for at least another 30 years. In this study, the potential impacts of mining activities on the soil and water environments have been evaluated. Water samples showed high concentrations of sulfate, calcium, magnesium, Mo, and arsenic, and high pH values in the order of high to low as follows: tailing water > Khangal River > groundwater. Statistical analysis and the δ2H and δ18O values of water samples indicate that the tailing water directly affects the stream water and indirectly affects groundwater through recharge processes. Soil and stream sediments are highly contaminated with Cu and Mo, which are major elements of ore minerals. Based on the contamination factor (CF), the pollution load index (PLI), and the degree of contamination (Cd), soil appears to be less contaminated than stream sediments. The soil particle size is similar to that of tailing materials, but stream sediments have much coarser particles, implying that the materials have different origins. Contamination levels in stream sediments display a tendency to decrease with distance from the mine, but no such changes are found in soil. Consequently, soil contamination by metals is attributable to wind-blown dusts from the tailing materials, and stream sediment contamination is caused by discharges from uncontained subgrade ore stock materials. Considering the evident impact on the soil and water environment, and the human health risk from the Erdenet Mine, measures to mitigate its environmental impact should be taken immediately including source control, the establishment of a systematic and continuous monitoring system, and a comprehensive risk assessment.  相似文献   

20.
The ores of the Yata gold mine in China are rich in arsenic and antimony, so the exploitation of this mine may also lead to the release of As and Sb to adjacent environments, such as stream water, stream sediment, soil, plants, and crops. To understand the environmental impact of mine tailings, samples of water, sediment, soil, plant and crop were collected and analyzed. In summer of 2005, the tailings dump was seriously flushed by a heavy flood, and the mine waste was transported far away. Samples were collected in December of 2004 and January of 2006, respectively, and the impact of the flood on the release of toxic elements was evaluated. The result shows that the Yata creek, which drains the mining area, was severely contaminated by As and Sb. The dissolved As and Sb in water are 86-1140 μg/L and 65-370 μg/L, the particulate As and Sb are 38-2100 μg/L and 25-420 μg/L, whereas As and Sb in the sediment are 190-760 μg/g and 69-210 μg/g, respectively. In water environment, As and Sb show a similar feature to SO4^2- since As and Sb exist dominantly as anions--H2AsO4^-, HAsO4^2- and SbO3^-. In contrast to Fe, Cu, Pb, Zn, which migrate mostly in particulate form, As and Sb tend to transport in dissolved form.  相似文献   

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