• Resources Recycling
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• v.19 no.6
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• pp.77-85
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• 2010

This study was carried out to develop a process flow sheet for recovering valuables (gold and high purity silica) from the gold mine tailings containing 1.7 g/ton of gold and 79.48 wt.% $SiO_2$. Float-sink tests using heavy liquids was conducted to explore the possibility of recovering gold by gravity separation. Hydrocyclone, froth flotation, and triboelectrostatic separatoin tests were conducted to recover high purity silica from the gold mine tailings. The results of float-sink tests showed that particles containing 5.58 g/ton of gold could be obtained at 2.72 specific gravity, but with very low yields around 3%. Meanwhile, all tests with hydrocyclone, froth flotation, and triboelectrostatic separation showed that high purity silica with $SiO_2$ content over 90% could be obtained. The purity could be improved further up to about 94% by employing several recleaning steps in the froth flotation and triboelectrostatic process.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.3
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• pp.148-154
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• 1998

Gubong gold-mine, previously one of the largest gold mines in Korea, is located at the mid-west of the South Korea. In the areas nearby the mine, the shallow groundwater was the major source for domestic and farming water-supply. Soil contamination by Cd, Cu, Pb and Zn was previously known in this area. This study is objected to identify quality of the shallow groundwater, possibly affected by the mine tailings. Samples were collected from a nearby stream, shallow groundwater and seepage from the tailings. Chemical analysis for the water quality includes major cations such as Na, K, Ca, and Mg, anions as F, Cl, NO$_3$, SO$_4$, HCO$_3$, and trace elements as Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd, Pb, Se, As, Hg. Water types could be drawn into four groups from the plots of Piper, Stiff diagrams and cluster analysis. SAR-Conductivity plot indicates the water does not pose either alkalinity or salinity hazards for irrigation. Major contaminant in groundwater appeared to be arsenic, released from arsenopyrites in tailings by oxidation. Dredging of buried railing materials could stimulate the release of arsenic from the sediments to the groundwater.

• Environmental Engineering Research
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• v.23 no.2
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• pp.189-194
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• 2018

The traditional gold mining in Kulon Progo district, Special Region of Yogyakarta Province produced tailings containing mercury (Hg) from the gold amalgamation process. Mercury accumulated in tailings has 164.19 mg/kg - 383.21 mg/kg in total concentration. Stabilization/solidification (S/S) is one of the remediation technologies to reduce waste pollution. Portland cement is one of the additive materials in S/S that effective encapsulates heavy metal waste. The aim of this research is to know the optimum composition of tailings mixture with Portland cement in S/S process. This research used variation of tailings composition. Variation of Portland cement composition with tailing are 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80 and 10:90. The result of this study found that the optimum composition of Portland cement: tailings was 10:90, with compression test of $257ton/m^2$ and TCLP test was 0.0069 mg/L. The compression test results were in accordance to US EPA Standard quality of $35ton/m^2$. TCLP test results meet the standard of Indonesian Government Regulation No. 101 Year 2014 of 0.05 mg/L.

• Resources Recycling
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• v.19 no.3
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• pp.9-15
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• 2010

Domestic gold mine tailings, generally, contain a lot of non-metallic silica and clay minerals. These minerals can be separated from the tailings by various physical separation methods and used as raw materials for cements and ceramic products. In these physical separation procedures, metallic complex sulfides, in which Au and metallic constituents such as Pb, As and Fe were concentrated, were obtained as a by-product. These metallic constituents should be removed or separated from the by-product to extract Au efficiently. In this work, removal and separation processes of Pb, As, and Fe from the by-product were investigated. Pb was removed to under 3% by using alkaline oxidative leaching at the leaching condition of $120^{\circ}C$, 2M NaOH, 100psi $Po_2$, 250r.p.m., 4 wt.% solid and 30 min. leaching time. The leached residue was roasted and separated magnetically to obtain a non-magnetic product contained <0.2% As, <3% Fe and high concentrated Au more than 8,000 ppm.

• Environmental Engineering Research
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• v.13 no.1
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• pp.33-40
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• 2008

Levels of arsenic in stream and reservoir waters affected by an abandoned gold mine were examined. The abandoned mine has been left without proper civil and remedial works preventing potential environmental hazards. Field and laboratory chemical analyses revealed that the stream waters downgradient from the mine area were severely contaminated with arsenic and furthermore the reservoir water, 2-3 km away from the mine, also contained substantial levels of As, far exceeding the Korean stream water standard. Relatively higher pH values (6.5-9.4) enhanced mobility of As and mainly sustained substantial As concentration in waters. Chemistries of the stream water, groundwater and reservoir water were dominated by two main factors including effects of mine effluent and anthropogenic agricultural activities. Considering that there has been a substantial As input to the reservoir and the reservoir water has been used for agricultural and domestic uses, immediate remedial works are essentially required.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.407-416
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• 1997

Soil, tailings, stream sediment and surface water samples collected in the vicinity of the Geumwang Au-Ag mine were analyzed in order to investigate the pollution level of heavy metals and to determine the dispersion patterns. Although the maximum concentrations of soils collected at the flotation plant and tailings dam were 9,270 ppm As, 17 ppm Cd, 1,480 ppm Cu, 10,080 ppm Pb and 18,400 ppm Zn, dispersion of heavy metals were limited in the vicinity of the flotation plant and tailings dam. This may be due to high pH values (> 8.0) of the soils by flotation solution for mineral processing. The pH values of water samples near the flotation plant and tailings dam were over 8.0 and Cd, Cu and Zn concentrations were not detected. The waters in the vicinity of Geumwang mine generally belong to a $Ca^{2+}-SO_{4}{^{2-}}$ $(HCO_3{^-})$ type.

• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.69-80
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• 1997

This investigation was conducted to provide information for characteristics of environmental pollution by the heavy metals from the abandoned gold mine in order to characterize the distribution patterns and environmental damages of the contaminants to the surrounding environment. Through analysis of CN, Cd, Cu, Pb, Zn, As, Cr, and Hg in a mine tailings, paddy soils, and stream sediments, the physico-chemical properties of the mine tailings and paddy soils were measured. The pH's were 5.4, 8.4 for the paddy soil and mine tailing, respectively. The maximum contents of CN, Pb, Cd, and As the in mine tailing were 99.98, 1,752.72, 31.88, and 298.50 mg/kg, respectively. The amounts of these ions were higher than the standard level of industrial area in Korea. The average content of CN and heavy metals in the paddy soils were higher than the background level of heavy metals in the unpolluted paddy soils around the mine. Especially, the contents of heavy metals in the paddy soils along the adjacent stream were higher compared to the paddy soil that was not influenced by the mine tailings. The contents of CN and heavy metals in the stream sediment close to the mine area were similar to those of the mine tailings, but decreased along the distance of the stream farther away from the tailings that was the source of these pollutants.

• Journal of Soil and Groundwater Environment
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• v.23 no.5
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• pp.17-25
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• 2018

The Boroo area in Mongolia is known to have been contaminated with heavy metals due to irregular gold mining activities and the release of mercury from gold extraction process. Soil and mine tailings were collected to analyze contamination patterns of heavy metals in the Boroo area. Analyses revealed that mercury, arsenic and cadmium concentrations exceeded the regulatory standard of the nation (Mongolia National Standard). In case of mercury, about 80% of the survey area was over the limit and the concentration distribution heavily influenced by influx of mercury through water transport. Soil contamination by arsenic was most severe that the concentration exceeded the regulatory limit in almost entire survey area, showing peak concentrations at nearby streams and river along with ore processing facilities. For cadmium, about 20% of the survey area was over the limit with the concentration distribution similar to that of arsenic.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.411-429
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• 2018

Daeyoung mine (also called "Daema mine") produced gold and silver from mainly gold- and silver-bearing quartz veins. The mine tailings are a waste hazard, but most of the tailings were swept away or dispersed throughout the area around the mine long before the tailing dump areas were transformed into agricultural land. Soil liner and protection facilities, such as retaining walls, were constructed in the mine area to prevent the loss of tailings. The content of the tailings is 3,424.41~3,803.61 mg/kg, which exceeds the safety standard by a factor of 45. In addition, contamination was detected near agricultural areas and in the sediments in downstream drainage channels. A high level of As contamination was concentrated near the waste tailings yard; comparaable levels were detected in agricultural areas close to streams that ran through the waste dump yard, whereas the levels were much lower in areas far from the streams. The contamination in stream sediments showed a gradual decrease with distance from the mine waste yard. Based on these contamination patterns, we concluded that there are two main paths that affect the spread of contaminants: (1) loss of mine waste, and (2) the introduction of mine waste into agricultural areas by floods after transportation by streams. The agricultural areas contaminated by mass inflow of mine waste can act as contamination sources themselves, affecting other agricultural areas through the diffusion of contaminants. At present, although the measured effect in minimal, sediments in streams are contaminated by exposed mine waste and surface liners. It is possible for contaminants to diffuse or spread into nearby areas if heavy elements trapped in soil grains in contaminated agricultural areas leach out as soil solution or contaminant particles during diffusion into the water supply.

• Resources Recycling
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• v.19 no.6
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• pp.61-69
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• 2010

S.M.C (DSME), only operating gold mine in Korea, is processing about 160 ton/day to recover gold and more than 150 ton/day of tailing is produced. Some portion of the tailings are used as a filler material after drying, but most of them are stored on the tailing dam. As a result of chemical analysis by a fire assay method, it contained Au 1.5~2.0 g/ton and 225~300 g per day of gold is getting discarded. It is urgent to develop a technology to recover and reutilize Au. In the present study, flotation tests were carried out to recovery gold for the tailings. Test results show that products with gold grade 21.31 g/ton(Au grade) and 62.73% (Au recovery) were obtained under the optimal conditions including KAX addition rate 97.2 g/ton, frother AF 65 (0.248 l/ton) and depressant sodium silicate (4 kg/ton), it's possible to recover one of the most valuable metal Au, by re-feeding to rougher flotation.