• Economic and Environmental Geology
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• v.4 no.3
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• pp.113-119
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• 1971

The Daeheung Dolomite Mine, which is about 6km south of Danyang, Chungcheongbugdo, is coincided with almost central portion of the Danyang quardrangle scaled in 1 : 50,000. The purpose of this report is to prepare a information for the economic evaluation on the mine. Geology of the region is composed of worm-eaten limestone, crystalline limestone, crystalline dolomite rock, sandstone and shale from bottom, those are applicable to socalled Dumugol and Maggol formation of Ordovician, and batholithic biotite granite is intruded the west-side of the ditto sedimentary rocks. The dolomite bed, emplaced in bottom of the upper limestone formation, so-called Maggol formation, is about 270m in thickness, and dips $30^{\circ}{\sim}50^{\circ}$ northwest. The facies of the dolomite rock contained many brucite crystals is not only coarse-grained crystalline, but also micro crystalline in contact metasomatic parts. 25 samples were taken from the two series, A and B, in the nearly crossed direction to the strike of the dolomite bed as shown in the geological map. They were chemically analysed on the components of MgO, CaO, and $SiO_2$ as shown in Table 2. The estimate ore reserves total some 107,200,000 metric tons above the 320m level with the following average contents: MgO 21.80%, CaO 29.27% and $SiO_2$ 0.64%. It is caused by brucite minerals that MaO content in the dolomite rock is higher than pure dolomite (21.7%). The dolomite ore is possible in use for magnesian fertilizer, magnesian cement and refractory material, especially the microcrystalline dolomite ore is useful for a refractory material in furnaces of iron industries.

• Economic and Environmental Geology
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• v.54 no.4
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• pp.475-482
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• 2021

This study proposed a strategy with literature review on effective monitoring of dispersion of the particulate matters (PM) emitted from domestic open pit lime mines. The mines generally produced a large amount of PM through the mine processes such as crushing and transportation of raw or crushed ores. The PM emission from mine facilities or transportation can be assessed using empirical equations which was prepared through the experimental tests to produce PM from ores. For effective monitoring of mine PM dispersion, this study showed a preliminary application of the monitoring network with multiple low-cost sensors around a main PM emission source for each mine site. Therefore, two domestic limestone mine sites were selected for this study, and install the monitoring network with low-cost PM sensors and LTE (Long-term evolution) data communication. Then, preliminary resultant PM data plotted according to monitoring duration showed typical PM dispersion patterns. The quantification of the PM dispersion patterns should be roughly prepared by a PM size-dependent dispersion modeling.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.463-473
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• 2000

This research was carried out to investigate chemical pretreatment using limestone in treating abandoned metallic mine drainage with anaerobic biological treatment, and to estimate application of papermill and livestock sludge as carbon sources for SRB (Sulfate Reducing Bacterial. Capacity of anaerobic limestone bed was steeply decreased. But if limestone was utilized as pretreatment process in treating them with anaerobic biological treatment. it could look forward to stabilize system because it did initally neutralize them. Effluent SCOD in R-4 was lower than R-l~R-3 in inital HRT 5day but its concentration was high in HRT 1day after passed time. Therefore in point of durability and supply of organic matter. it seemed that R-4 was useful became organic matter in R-4 was not consumed by excessive degradation within short period. In all reactors, pH was suitable for SRB growth in whole HRT, but on the evidence of ORP, SRB was active after HRT 2day. Fixation trend of heavy meta s showed high as $SO_4{^{2-}}$ reduction efficiency increased, and $SO_4{^{2-}}$ reduction and fixation of heavy metals were relatively high in HET 2day.

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.63-72
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• 2013

This study estimated stabilization efficiency of As and heavy metal contaminated agricultural soil in abandoned mine through pot experiment. Also contaminants uptake of plant (lettuce) was compared as function of amendment (limestone, steelmaking slag and the mixture of these) addition. In soil solution analysis, concentration of contaminants in soil solutions which added limestone or steelmaking slag were lower than that of the mixture. Especially in As analysis, concentration with 5% (wt) addition of steelmaking slag showed the lowest value among those with other amendments. This seems that As stabilization happens through Fe adsorption during precipitation of Fe by pH increasing. Leachability of As in stabilized soil by TCLP was represented similar result with soil solution analysis. However leachability of heavy metals in stabilized soil was similar with that of non-stabilized soil due to dissolution of alkali precipitant by weak acid. Contaminants uptake rate by plant was also lower when limestone or steelmaking slag was used. However this study revealed that concentration of contaminants in soil solution didn't affect to the uptake rate of plant directly. Because lower $R^2$ (coefficient of determination) was represented in linear regression analysis between soil solution and plant.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.71-74
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• 2001

AMB(Acid Mine Drainage), characterized as high concentration of metal & sulfate ions and low pH(2.0~4.0), is the world-wide problem wherever there is or has been mining activities. Though limestone has been generally used to neutralize AMD, There are metal hydroxide precipitation on the surface of limestone and excessive alkalinity formation which exceeds the regulation. In this research, concrete-recycled fine aggregate is selected for alternative neutralizing agent. Because fine recycled aggregate had more ANP than others in the preliminary research, the purpose of this research is to apply fine aggregate for AMD neutralization. Three columns packed with fine aggregates(2.5mm$O_3$) of it is calculated as 0.09(C-1), approximated 10% purity of limestone. Comparing with values of other columns(C-2: 0.01 and C-3: 0.01), there is variation of porosity and residence time induced from the precipitation of metal hydroxide. Consequently, 8 hours of HRT is enough to create adequate alkalinity and the function which could expect the variation of porosity(n) and residence time( $t_{R}$) should be applied to develop design function.lied to develop design function.

• Tunnel and Underground Space
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• v.24 no.6
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• pp.430-439
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• 2014

This study developed a simulation program for truck-loader haulage systems in an underground mine. A limestone underground mine in Korea was selected as a study area and investigated to design the simulation algorithm for truck-loader haulage systems. GPSS/H simulation language was utilized to develop the simulation program. Simulations were conducted to analyze the optimal number of haulage trucks dispatched in the 540 ML loading point by using the developed program. The simulation results showed that 8 trucks can maximize the daily production (2,076 ton). The real production (1,850 ton/day) of limestone ores was very similar to the simulated one (1,850.35 ton/day) when considers 7 trucks dispatched in the 540 ML loading point. In addition, average waiting time at loader were similar (waiting time by time study : 1.39 min, simulated waiting time : 1.35 min).

• Economic and Environmental Geology
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• v.28 no.3
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• pp.213-220
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• 1995

Geochemistry of stream water and sediment collected in the vicinity of the Donghae coal mine in the Samchuk coalfied were investigated in order to evaluate the environmental impacts of acid mine drainage. The pH of stream water ranges from 2.85(at 2 km away from the mine) to 7.92(at uncontaminated tributary). The main cation and anion species in the upper stream are $Ca^{2+}$ and $SO_{4}{^2-}$, respectively. The level of pH and the amount of $HCO^{3-}$ in stream water increase to the downstream and where uncontaminated small tributaries are joining, and in the area covered with limestone. From the results of thermodynamic calculation, the main forms of iron in stream water are estimated as $Fe^{2+}$ and $FeSO_{4}{^0}$, and most of them could be precipitated as FeO(OH) with increase of pH. The white precipitates in stream sediments particularly found around the coal mine are proved to be $Al(OH)_3$ by XRD and XRF analysis. As a result of investigation for seasonal variation of AMD, the level of pH decreased and conductivity increased in dry season.

• Tunnel and Underground Space
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• v.8 no.2
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• pp.118-129
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• 1998

A three dimensional boundary element method-BEAP3D was applied to the stability analysis of the mine openings not only to improve the stability during mining operations but also to serve the evaluation of the mine openings for further utilization. Stability analysis on the stability of the room-and-pillar stopes underneath of the old mine openings and the openings to be created by the newly proposed sublevel stoping method at the Nowhado Pyrophyllite Mine, showed that rock mass around the old and new stopes would be stable. Six stopes of a sublevel stoping designed for the Choongmu Limestone Quarry would be stable, too. A sublevel stoping method consisting of six stopes was similarly suggested for the Keumpyung Quartzite Mine. The stability can be guaranteed through out six stopes. Since mining starts from the bottom 1st sublevel to the uppermost sublevel, the safety of the stopes will improve together with the mining process. It would highly be recommended to investigate in-situ rock properties and the rock stresses for future studies. Even though the rock around the uppermost part and bottom of all the stopes have a very high factor of safety, spot reinforcements such as rock bolting would be recommended to mitigate the intermediate and minor principal stresses acting in a tensile mode.

• Economic and Environmental Geology
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• v.25 no.1
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• pp.1-16
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• 1992

The Wondong Fe-Pb-Zn deposit is located in endo and exoskarns formed along the contact between the Makkol limestone interbedding pelitic limestone of Ordovician age and quartz porphyry of Cretaceous age. At the Wondong mine, the endoskarn shows a discontinuous zonal arrangement from quartz porphyry to pelitic limestone as follows: unaltered quartz porphyry, weakly altered quartz porphyry zone, intensively altered pinkish quartz porphyry zone, garnet zone, and greyish white and fine-grained clinopyroxene zone developed at pelitic limestone side. In terms of chemical mass balance, intensively altered pinkish quartz porphyry relative to unaltered quartz porphyry shows substantial enrichments in $K_2O$, $Na_2O$, and HREE and depletions in MgO, CaO, total $Fe_2O_3$, and LREE. On the other hand, garnet zone of endoskarn is enriched in CaO, MnO, total $Fe_2O_3$, MgO and depleted in $K_2O$, $Na_2O$. $Al_2O_3$ seems to be determining inert component. Thus the behavior of elements indicates that the mobility of elements depends on the equilibration of hydrothermal fluid and minerals and affects on enrichments by fractionation from and depletions by partition to hydrothermal fluid, respectively. Traversing toward pelitic limestone from a central zone of exoskarn, the exoskarn also shows a zonal arrangement as follows: garnet zone, clinopyroxene zone, and decolored pelitic limestone. The arrangement of mineral assemblages in skarns of the Wondong mine is the result of an increase in CaO and $K_2O$ toward the pelitic limestone. Skarn and ore minerals were formed in the following sequence: early skarn, late skarn and magnetite, pyrite, sphalerite, galena, and molybdenite. On the basis of stabilities of mineral assemblages, physicochemical conditions of the late skarn and magnetite mineralization are estimated to be $350^{\circ}C{\leq}T{\leq}400^{\circ}C$ at 1 Kb, $-23{\leq}log\;fO_2{\leq}-18$, and $0.005{\leq}XCO_2{\leq}0.01$, while those of the early skarn to be $420^{\circ}C{\leq}T{\leq}550^{\circ}C$ at 1 Kb.

• Tunnel and Underground Space
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• v.33 no.5
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• pp.388-398
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• 2023

The changes in groundwater flow due to mining development act as a contributing factor to major issues such as ground subsidence, strength reduction and collapse. For the sustainable mining development, measures for dealing with fluctuations in seasonal underground water inflow, power losses, pump damage, and unexpected increases in inflow must be put in place. In this study, the aim is to identify the causes of underground seepage through the examination of hydrological connectivity between the study area and nearby limestone mine. A tracer tes for assessing subsurface connectivity has been planned. A variety of tracers, such as dyes and ions, were applied in lab test to select the optimal tracer material, and a hydrological model of the study area was implemented through field test. Finally, the hydrological connectivity between the external stream and underground water in the mine was analyzed.