• Tunnel and Underground Space
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• v.19 no.3
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• pp.248-260
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• 2009

With regard to oversea mineral resources development, recent trend has been changed from a simple capital investment to a direct development of the resources. In relation to the stability of a slope in large open-pit coal mine, groundwater system was investigated and the validity of horizontal drainage hole was evaluated in Pasir coal mine, Indonesia. In this work, various field tests were carried out for a characterization of groundwater system, which included in-situ permeability measurement, tracer test and monitoring of groundwater levels. Especially, the influence of SM river on the characteristics of the groundwater flow system was mainly inspected. For the permeability measurement, Guelph permeameter was employed, and was found that sandstone was more permeable than mudstone and coal seam. From a comparison of lithological structure and the results of groundwater level monitoring, sandstone and thin coal seam with fractures were found to be a main channel for groundwater flow. In the results of tracer tests, the effect of SM river on the groundwater system depends on the geological structure of its base. To identify the effect of horizontal drainage holes, 2-D groundwater modeling was performed. Four different cases were tested, which are different from the length of drainage hole and the existence of pond on top of the slope. To enhance the drainage effect and slope stability, the drainage hole should be drilled to the depth of coal seam layer, which provides a main pathway of groundwater flow and embedded by sandstone. For this purpose, correct identification of surrounding geology should be preceded.

• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.112-118
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• 2012

Fine suspended solids from mine drainage draw attentions due to their potential adverse influences on the water quality, such as increasing turbidity and degrading aesthetic landscape. Currently, sand filter beds are adapted in some mine drainage treating systems. However, more efficient system is in demand, as the existing sand beds reveal some problems, such as frequent maintenance intervals. Various filtering mediums including fly ash, mine tailing aggregates and the sand were tested for improving the current system, using column experimental set-up. Mine drainage samples were collected from the current treating systems in the abandoned H coal mine. The experiment was run for 7 days. Suspended solids recorded as 100.9 mg/L and the value exceeds the current standard, 30 mg/L. Sand was proved to still be the optimum medium for the fine suspended solids, compared to fly ash and fly ash + sand. Mine tailing aggregates were placed at the exit of the columns, substituting gravels. The tailing aggregates is made by mine tailings and clay. Sand bed filters can also be improved by mixing granular activated carbon, which was found to be economical and efficient in the batch experiment, conducted at the same time.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.3
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• pp.116-121
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• 1997

Pilot wetland reactor systems to test acid mine drainage treatment efficiencies for metals were designed and operated at the Dalsung mine and surveyed the operating problems. pH and Eh (redox potential) were measured in situ and anayses of Cd, Pb, As, Zn, Cu, Fe, Al and Mn were carried out in the laboratory. Maximum metal removal efficiencies of the reactor containing the rice stalks, the cow manure and limestones were that Cu, Zn, Fe, Cd, Al, Mn and Pb were lowered by 98%, 100%, 99%, 100%, 97%, 61% and 100%, respectively and at that time the pH and Eh of the effluents from the reactor were 6 and about -300 mV. However, the redox potential was raised and removal of metal elements except aluminium was decreased with operation time. It suggests that the reduced condition is very important for the metal removal. During the operation, problems such as scaling in pipes and volume change of the substrate within the reactor occurred, which were preventing the flow of main drainage in pipes and reactor.

• Tunnel and Underground Space
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• v.21 no.5
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• pp.370-376
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• 2011

To design the drainage system of a mine, it is very important to evaluate the groundwater inflow to the mine workings. In this study, continuous steady state flow through rock mass around mine openings developed in Sungok area of Gagok Mine was analyzed. Saturated only model and Saturated/unsaturated model were used as material models of rock mass. Groundwater quantities flowing into Sungok 160 level which is 1216 m long are computed as 1450 $m^3$/day in case of a saturated model and as 1071 $m^3$/day in case of a saturated/unsaturated model. An effect that hydraulic conductivity has on inflow turned out be greater than precipitation and inflow increased linearly with increase of hydraulic conductivity. It was found that change of hydraulic conductivity ratio and orientation have an impact on the variation of inflow and water table.

• Economic and Environmental Geology
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• v.54 no.6
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• pp.689-698
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• 2021

Since the mine reclamation scheme was implemented from 2007 in Korea, various remediation programs have been decontaminated the pollution associated with mining and 254 mines were managed to reclamation from 2011 to 2015. However, as the total amount of contaminated mine drainage has been increased due to the discovery of potential hazards and contaminated zone, more efficient and economical treatment technology is required. Therefore, in this study, the adsorption properties of arsenic was evaluated according to the adsorbents which were derived from water treatment sludge(Alum based adsorbent, ABA-500) and granular ferric hydroxide(GFH), already commercialized. The alum sludge and GFH adsorbents consisted of aluminum, silica materials and amorphous iron hydroxide, respectively. The point of zero charge of ABA-500 and GFH were 5.27 and 6.72, respectively. The result of the analysis of BET revealed that the specific surface area of GFH(257 m²·g^-1) was larger than ABA-500(126~136 m²·g^-1) and all the adsorbents were mesoporous materials inferred from N₂ adsorption-desorption isotherm. The adsorption capacity of adsorbents was compared with the batch experiments that were performed at different reaction times, pH, temperature and initial concentrations of arsenic. As a result of kinetic study, it was confirmed that arsenic was adsorbed rapidly in the order of GFH, ABA-500(granule) and ABA-500(3mm). The adsorption kinetics were fitted to the pseudo-second-order kinetic model for all three adsorbents. The amount of adsorbed arsenic was increased with low pH and high temperature regardless of adsorbents. When the adsorbents reacted at different initial concentrations of arsenic in an hour, ABA-500(granule) and GFH could remove the arsenic below the standard of drinking water if the concentration was below 0.2 mg·g^-1 and 1 mg·g^-1, respectively. The results suggested that the ABA-500(granule), a low-cost adsorbent, had the potential to field application at low contaminated mine drainage.

• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.1-11
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• 2006

Attempts were made to analyze the national policy of soil contamination prevention and management of inactive or abandoned metal (IAM) mines in Korea. This approach focused on legal systems and legislation, remediation technology development, and the arrangement or distribution of budgets pertaining to national policy since the mid 1990's. Prevention of Mining Damage and Recovery Act enacted. Defines the roles, responsibility and budget of the government when recovering mine damages. However, in 2005 there still remains to improve the national policy of soil contamination prevention and management of IAM mines. Analysis of national and industrialized foreign countries including the United States, the United Kingdom, and the Netherlands suggest the following improvements: i) arranging distinct regulations between strict and non-strict liability criteria for potentially responsible parties; limiting innocent and non-strict liability depending on the period of incurred mining activity, ii) enhancing participation of local communities by enforcing law and legislation, iii) establishing a national database system of (potentially) IAM contaminated sites based on the Website-Geographic Information System, iv) carrying out site-specific risk assessments and remediation of IAM contaminated sites, v) preparation and distribution of clean-up fund at mine sites adequately, and vi) technology development for the cleaning of IAM contaminated sites; awarding positive incentives of a legal nature for participants applying newly developed technology in IAM mines.

• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.13-24
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• 2004

This study was carried out to plan the prevention of the generation and discharge of Acid Rock Drainage (ARD). The Acid Base Accounting(ABA) test was performed for geological materials such as pit wall, waste rock and stream sediments near the Imgi abandoned pyrophyllite mine in Busan, Korea. In addition, hydraulic characteristics were tested with the disk tension infiltrometer around the waste rock dump. Maximum Potential Acidity(MPA) of geological materials near the Imgi mine was 246.942kg $H_2SO_4/t$, and maximum Acid Neutralising Capacity(ANC) was 8.7kg $H_2SO_4/t$. These results indicate the pit wall and waste rock, except most of stream sediments are acid generating geological materials. These have salt and free hydrogen ion which resulted from oxidation of sulfides. Hence they could be convert rain water to acid rock drainage. Although the waste rock dump of the Imgi mine have very low infiltration rate, slopes of the waste rock dump have many "V" type erosion gullies and multi-layers. These gullies and multi-layers have coarse clastic particle layers which have very large hydraulic conductivity. Through this coarse clastic particle layer a large part of rain flow into ground. And also this layer could function as aeration path which induced oxidation of sulfide minerals and generation of ARD continuously.

• Journal of the Mineralogical Society of Korea
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• v.17 no.1
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• pp.37-47
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• 2004

Sulfates such as alunite and schwertmannite formed under oxidation condition play a important role in geochemical processes taken place at waste dumps and a creek from Dalseong mine, Daegu. Water chemistry shows pH decreases from upstream toward downstream creek, mainly due to formation of schwertmannite that is the most abundant phase along the creek. The removal of Al from the creek is preferentially attributed to formation of Al-bearing minerals and Al-sulphates. Among them, alunite is the most important Al-sink phase that occurs at higher pH than $pK_1$, Al hydrolysis constant. With high saturation index, alunite formed at the creek has a spherical form, commonly associated with schwertmannite. Secondary minerals formed on the surface of altered or weathered surfaces of heavy metals from the wasted dump that underwent severe oxidation, where alunite has characteristic habits which are spheric, radiating, and botrytis-like aggregates. Natroalunite occurs in association with alunite, or as mixtures of both of them. Because the pH decreases with distance due to formation of schwertmannite, although total contents of dissolved ions slowly lessen at least in the AMD, it is expected that the minerals precipitated at the creek can be exposed to subsequent dissolution, which may induce possible environmental problems.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.563-570
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• 2005

The purposes of this study are to examine a field test on heavy metal removal efficiency for AMD(Acid Mine Drainage) using fish bone and apatite, and to compare those results of the laboratory & the field tests. The duration of the field test was about one month and flow rates of AMD varied from 2.53 l/min to 12.8 l/min. From the result of the field test, removal efficiencies of apatite and those of fish bone are high for As, Fe, and Pb while those of fish born is higher than those of apatite far Al, Cd, Cu and Zn which are similar to the result of the previous laboratory test. In particular, average arsenic removal efficiency of apatite is higher$(84\%)$ than that of fish bone$(75\%)$ like the result of the previous laboratory test. In case of precipitates of phosphate compounds which are generated from chemical reaction between apatite/fish bone and AMD, those generated from apatite/AMD reactionform powder-shape while those created from fish bone/AMD reaction seem to be sludge. Therefore, apatite will be used as a precipitant for mine drainages having wide range of pH based on previous studies while fish bone will be applied as a precipitantfor AMD having lower PH and high concentration of heavy metals.

• Journal of the Mineralogical Society of Korea
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• v.29 no.4
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• pp.199-207
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• 2016

One of the most significant environmental issues in abandoned coal mine is acidic drainage which gives rise to the many environmental problems that acidifying streams water, sedimentation of iron/aluminium hydroxide, and pollution of water and soil. Water and precipitate samples for experiments were collected from stream and bottom in the pit mouth of Sambong mine. Mine water shows pH range from 7.24 to 7.94 in winter and 3.87 to 5.73 in summer season. The EC shows range from 432 to $897{\mu}S/cm$ at the stream receiving mine water. The highest concentrations of cations such as Mg, Al, Ca, and Mn are showing 15.50, 4.56, 85.30, 12.76 mg/L in the pit mouth, respectively. The reddish brown precipitates (Munsell color 10R-5YR in winter and 2.5YR-5Y in summer) consist mainly of 2-line ferrihydrite and schwertmannite. The precipitates are characterized by rod or cylindrical forms, and coccus or sphere of 0.1 to $0.5{\mu}m$ in diameter.