• Journal of Environmental Science International
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• v.15 no.3
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• pp.279-286
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• 2006

Electrokinetic technique was considered in removing arsenic from the abandoned mining tails. In order to estimate the removal characteristics of arsenic, the sequential extraction analysis and desorption experiment were carried out prior to the application of electrokientic process. The result of sequential extraction analysis indicated that the water soluble and exchangeable fraction, easily leachable to ground water, were very low as much as about 2.5% and the fraction except residual (38.3%), possibly extractable under very acidic or alkalic environment, was about 59%. In the result of desorption test using four different kinds of electrolytes, the mixture of citric acid and sodium dodecyl sulfate (SDS) showed the highest desorption efficiency as much as 77.3%. The removal efficiencies of arsenic from mining tailings by electrokinetic process under the different electrolyte environments were slightly low and resulted in the following order: citric acid + SDS (18.6%) > 0.1 $NHNO_3$ (8.1%) > HAc (7.4%) > Distilled water(6.6%). Also, arsenic in soil matrix was moved favorably in the direction of anodic rather than cathodic region, which is opposite trend with cationic metal ions generally existing in soil, because anionic form of arsenic is dominated in acidic soil caused by the movement of acid front form anode.

• Journal of the Korean Chemical Society
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• v.12 no.3
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• pp.81-84
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• 1968

Stabilities of chelates of 7-nitroso-8-hydroxyquinoline-5-sulfonate have been determined for divalent transition metal ions, Mn(Ⅱ), Fe(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), and Zn(Ⅱ) by means of the Calvin-Bjerrum technique. Comparison of these stability constants with those obtained for 8-hydroxyquinoline, and 8-hydroxyquinoline-5-sulfonate shows that the observed differences are essentially the results of the lower basicity of the sulfonated group and different metal-ligand bond. The divalent metal chelate stability sequence is not in agreement with the reported metal orders for other chelating agents. The stabilities were found to follow the order Mn(Ⅱ) < Fe(Ⅱ) ${\approx}$ Co(Ⅱ) > Ni(Ⅱ) < Cu(Ⅱ) > Zn(Ⅱ).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.24-27
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• 2005

This study has focused on investigation on As and heavy metal contamination derived from metalliferous mining activities in the Choongbuk Province in Korea. Soil, mine effluent, surface water and ground water samples were taken in and around 27 abandoned metal mines, and analyzed for As, Cd, Cu, Ni, Pb and Zn using AAS and anions in water samples using IC. In general, the heavy metal concentrations in soils decreased with Increasing distance from the each mine audit. Tailings and mine waste soils from several mines contained over the guideline of Soil Conservation Act in Korea. Soil samples from the Seobo, Honga, Daehwa, Jeungjadong, Youngbo and Munbaek mines contained over the action levels of the metals due to intensive mining activities. Therefore, a proper remediation work needs to control the metal dispersion around the mines.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.260-270
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• 2008

The economics of manganese nodules mining was assessed based on 36 scenarios which reflect recent changes of the metal market. Those scenarios included optimistic/neutral/pessimistic prospect for the cost, 2 production scales(1.5 MT and 3 MT) and 6 assumptional paths of future metal prices. A large part of scenarios, in which optimistic or neutral prospect for the cost and metal prices were assumed, showed good economic feasibility of the project. For example, 37.12% of Internal Rate of Return(IRR) was obtained in the scenario of 3 MT production, neutral cost prospect and present metal price maintained in the future.

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.171-187
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• 2006

The status of heavy metal contamination was investigated using chemical analyses of stream waters and sediments obtained from Samsanjeil and Sambong Cu mining area in Goseong-gun, Gyeongsangnam-do. In addition, the degree and the environmental risk of heavy metal contamination in stream sediments was assessed through pollution index (Pl) and danger index (DI) based on total digestion by aqua regia and fractionation of heavy metal contaminants by sequential extraction, respectively. Not only the degree of heavy metal contamination was significantly higher in Samsanjeil area than in Sambong area, but its environmental risk was also revealed much more serious in Samsanjeil area than in Sambong area. The differences in status and level of contamination and environmental risk between both two mining areas may be attributed to existence of contamination source and geology. Acid mine drainage is continuously discharged and flows into the stream in Samsanjeil mining area, and it makes the heavy metal contamination in the stream more deteriorated than in Sambong mining area in which acid mine drainage is not produced. In addition, the geology of Samsanjeil mining area is mainly comprised of andesitic rocks including a small amount of calcite and having lower pH buffering capacity fer acid mine drainage, and it is likely that the heavy metal contamination cannot be naturally attenuated in streams. On the contrary, the main geology of Sambong mining area consists of pyroclastic sedimentary Goseong formation containing a high content of carbonates, particularly calcite, and it seems that these carbonates of high pH buffering capacity prevent the heavy metal contamination from proceeding downstream in stream within that area.

• Economic and Environmental Geology
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• v.29 no.6
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• pp.665-676
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• 1996

Domestic metal mines have contributed to the national industrialization of Japan for over a century through their stable supply of raw materials. However, due to the changes which have taken place in the industries structure, mining industry has been shifted to downstream industries. At present, only three major mines are in production. In recent times, changing economic conditions have made it increasingly difficult to develop new base metal mines. Subsequently, the deposit type targeted has shifted from base metals to epithermal associated gold deposits which, if of sufficient grade and tonnage, can be economical. Accompanying the dramatic rise in the price of gold during the late 1970's, has been an increase in the geological information and our understanding of epithermal gold deposits around the Pacific rim region. In particular, the common acceptance of the plate tectonic theory and the correlation's between modem geothermal systems and fossil epithermal systems were most important developments. In 1988, the Mining Council authorized the domestic exploration of 19 districts, targeting epithermal gold mineralization. Since 1989 the Metal Mining Agency of Japan, semi-government organization, has been conducted gold exploration in such area. With new genetic concepts and new technologies, promising gold mineralization has been discovered. Two such areas which are at an advanced stage of exploration are Seta, in northern Hokkaido, and Noya, in central Kyushu.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.271-281
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• 2014

BACKGROUND: Application of the transfer functions derived from local soil data is necessary in order to develop proper management protocols for agricultural soils contaminated with heavy metals through phytoavailability control of the heavy metals. The aim of this study was to derive the transfer functions of Korean agricultural soils affected by the abandoned mining sites and evaluate suitability of the derived transfer functions. METHODS AND RESULTS: 142 agricultural soils affected by the abandoned mining sites were collected and analyzed. Two extraction methods, including 1 M $NH_4NO_3$ extraction and 0.01 M $Ca(NO_3)_2$ extraction were applied to determine phytoavailable metal pools in soils. Multiple stepwise regression of phytoavailable metal pools against the corresponding total metal concentration and soil properties was conducted to derive suitable transfer functions for estimating phytoavailable heavy metal pools. Applicability of the derived transfer functions was examined by calculating NME and NRMSE. CONCLUSION: Soil pH and organic matter were valid variables for derivation of the transfer functions which were applicable for estimating phytoavailable metal concentrations in the soils being contaminated by heavy metals. In addition, it was confirmed that transfer functions need to be developed based on local soil conditions to accurately estimate heavy metal-phytoavailability.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.63-72
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• 1999

In order to examine the contamination levels of trace elements in stream sediments in the Chungnam coal mine area, stream sediment and water samples were collected and analyzed for trace elements. The pH of stream water was neutral or weak-alkaline and the mobility of metal in stream sediments was supposed to be low. From the result of cluster analysis, non-polluted sampling stations can be distinguished from polluted sampling stations influenced by mining activities. The trace element concentrations in sediments from non-polluted zone were considered to be the natural backround concentrations of this area. The trace element concentrations in sediment samples from the mining area were higher than those from non-polluted area, and contaminated area of enriched trace element levels need to be properly managed. From the results of discriminant and regression analyses, concentrations of Cd, Cu, Pb AND zN and predicted values of Be, Mo, and Ni in Chungnam coal mine area were found to be lower than those in metal mining areas in Korea.

• Ocean and Polar Research
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• v.27 no.4
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• pp.477-490
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• 2005

The development of manganese nodule mining technology is very important in order to secure a long-term and stable supply of rare strategic metals. In the twenty years following the R&D activities with the international consortia in the 1970s, studies on mining technologies have been carried out by several national projects in Korea. The current metal prices such as copper, nickel, cobalt, and manganese have been drastically changed since 2002. Rapid economic growth of Asian countries, especially China, have induced the situation. And the possibility of copper shortage is looming just around the comer. Because of the imbalance between production and consumption, copper is fundamentally the most threatened metal in the future in terms of potential metal shortage. Manganese nodules contain a considerable percentage of copper as the future metal resource. Therefore, it is necessary to concentrate our effects on developing these resources. This paper introduces our evaluation of R&D progress for the development of manganese nodules. The issue and role of manganese nodules during the difficult period of a potential future metal shortage period is discussed and its prospect outlined. Also, this paper tried to emphasize the necessity of continuous R&D efforts for the commercial development of such mineral resources.

• Economic and Environmental Geology
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• v.38 no.4 s.173
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• pp.411-419
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• 2005

The recent rapid economic growth of China has an increasing interest to Korea. China is plentiful of the natural mineral resources and has a huge territory with 1.3 billion people, also has a strong foundation in the mining industry as a mineral process and metallurgical technology. Such strong mining industry of China is attractive to Korea which is getting ready the North East Asia epoch. The growth of big mining groups as Gangseo (Jiangxi) Copper Corporation and Honam Juyawhageo (Hunan Zhuye Torch) Metal Co. Ltd. haul up the rapid economic growth in China.