• Journal of the Korean Society of Groundwater Environment
• /
• v.6 no.4
• /
• pp.194-205
• /
• 1999

Hydrogeochemical variation and environmental isotope at the some abandoned metal mine (Sanggok, Keumsil, Jangpung and Samdeok) creeks of the Hwanggangri mining district were carried out based upon the physicochemical properties for surface water collected of February in 1998. Hydrogeochemical composition of the all water samples are characterized by the relatively significant enrichment of Ca$^{2}$, alkaline ions, N $O_3$$^{－}$ and Cl$^{－}$ in normal surface water, whereas the surface waters near the mining area are relatively enriched in Ca$^{2+$, Mg$^{2＋}$, heavy metals. HC $O_3$$^{－}$ and S $O_4$$^{2－}$. Surface waters of the mining creek have low pH, high EC and extremely high concentrations of TDS compared with surface water of the non-mining creeks. The range of $\delta$D and $\delta$$^{18}$O values (SMOW) in the waters are shown in －65.0 to－71.2$\textperthousand$ and －9.1 to－10.2$\textperthousand$. The d($\delta$D－$\delta$$^{18}$O) value with those of water samples ranged from 7.3 to 10.9. These $\delta$D and $\delta$$^{18/}$ of the acid mine water are more heavy values than those of surface water. The values have revealed the positive correlation between isotopic compositions and major elements, because those $\delta$D and $\delta$$^{18}$O values increase with increasing TDS. HC $O_3$$^{－}$ , S $O_4$$^{2－}$ and Ca$^{2＋}$ concentration. Using WATEQ4F, saturation index of albite calcite, dolomite and mostly clay minerals in water of the mining area show undersaturated and progressively evolved toward the equilibrium condition due to fresh water mixing, however, surface waters of the non-mining area are nearly saturated and/or supersaturated. Geochemical modeling showed that mostly toxic heavy metals within water in the mining creek may exist largely in the from of metal-sulfate (MS $O_4$$^{2－}$), free metal (M$^{2＋}$/), C $O_3$$^{－}$ and/or OH$^{－}$ complex ions. Based on the geology, water chemistry and environmental istopic data the water compositions from the Sanggok and Keumsil mine creek (consist mainly of Cambro-Ordovician carbonate rocks of the Cho-seon Supergroup) show higher PH, Ca$^{2＋}$, Mg$^{2＋}$ , HC $O_3$$^{－}$ and more heavy $\delta$D and $\delta$$^{18}$O values than those from the Jangpung and Samdeok mine creek (consist of age -unknown metasedimentary rocks of the Ogcheon Supergroup and/or Jurassic grani-toids), but each of these waters represents a similar hydrogeochemical evolution path by the mine water mixing.

• Korean Journal of Environmental Agriculture
• /
• v.20 no.1
• /
• pp.20-27
• /
• 2001

Stream water chemistry in the abandoned Boeun Jeil coal mine area was studied for a period of 3 months, including rainy and dry season. The stream waters were a nearly neutral and slightly alkali condition, and $Mg-SO_4$ type with Mg>Ca>Na>K and $SO_4>HCO_3>Cl>NO_3$. Chemical composition of the stream water was quite irregular during the experimental period. Concentrations of Na, K, $HCO_3$, U, Sr, and Cr decreased by $10{\sim}30%$ during rainy season, caused by dilution effects with rain. The concentration of Ca, Mg, $NO_3$, Cd, and Co increased during the rainy season, caused by more easily dissolved from bedrocks or mine drainage with slightly acidic condition than dry season. The stream water was enriched in Mg, Ca, $HCO_3$, $SO_4$, Al, Fe, Zn, Ni, Co, Cr, Cd, Sr and U. Concentrations of Na, Mg, Ca, $SO_4$, $HCO_3$, Fe, Zn, Ni, Sr, and U decreased linearly with distance from the mine adit. These elements were strongly controlled by dilution of unpolluted water influx and/or adsorption on the clay minerals and iron oxyhydroxide precipitates. This mine area exhibited two main weathering processes ; 1) oxidation with acidification derived from Fe sulphides, and 2) pH buffering due to Ca and Mg carbonate dissolution. This weathering processes were followed by adsorption of metals on iron oxyhydroxides and precipitation.

• Journal of the Korean earth science society
• /
• v.34 no.6
• /
• pp.575-587
• /
• 2013

DC electrical and electromagnetic survey was applied to evaluate the reserve of an iron mine site. We analyzed the borehole cores and the cores sampled from outcrops in order to decide which geophysical method was efficient for the evaluation of iron mine site and to understand the geological setting around the target area. Based on the core tests for specific weight, density, porosity, resistivity and P-wave velocity, showing that the magnetite could be distinguishable by the electrical property, we decided to conduct the electrical survey to investigate the irone mine site. According to previous studies, the DC electrical survey was known to have various arrays with high resolutions effective to the survey of the iron mine site. However it was also known that the skin depth is too shallow to grasp the deep structure of iron mine. To compensate the weakness of the DC electrical method, we applied the MagnetoTelluric (MT) survey. In addition, a Controlled Source MT (CSMT) method was also applied to make up the shortcoming of MT method which is weak for shallow targets. From the DC electrical and MT survey, we found a new low resistivity zone, which is believed to be a magnetite reserve beneath the old abandoned mine. Therefore, this study was confirmed for additional utility value.

• Economic and Environmental Geology
• /
• v.41 no.4
• /
• pp.453-464
• /
• 2008

This study is to examine a relation between coal mining subsidence occurrence at abandoned underground coal mines and underground goaf with respect to surface geology, subsurface structure, depth and thickness of coal beds and the distribution of drifts. A study is carried out at the site where susceptibility of coal mining subsidence was proven high in a previous study. In that previous study, the susceptibility of coal mining subsidence was spatially analyzed by GIS using digitized geological maps, investigation reports, digitized mining tunnel maps without consideration of subsurface structure and the multi-level arrangement of drifts. Here we analyze geological characteristics around the goaf and the distribution of coal seam based upon digitized geological maps and investigation reports on the study area. And digitized mining tunnel maps are also used to analyze the depth and multi-level arrangement of drifts. The results show that weakened surface rock strength, relatively shallow depth and large thickness of coal seam below the surface are closely related to the coal mining subsidence occurrence. Complicatedly inter-connected drifts, shallow depth of drifts and surface rock fractures are revealed as additional control factors affecting coal mining subsidence. These factors examined in this study as well as original factors should be taken into account for the quantitative estimation of coal mining subsidence occurrence at abandoned underground coal mine.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.54 no.3
• /
• pp.1-9
• /
• 2012

As topographic characteristics of Korea where 64 % of the national land area is forest and only 17 % is being used as farmland, remediation of farmland contaminated by heavy metals is a considerably important issue. In this study, as an alternative of practically and effectively remediating farmland which was abandoned as its crop plants exceeded maximum residue limit of heavy metals due to mining impact, applicability of stabilization method was examined through the pilot-scale field experiment. Three plots ($L{\times}W{\times}D=3m{\times}2m{\times}0.3m$) were installed at the selected farmland and in plot 1, only soil of the selected farmland was applied, in pilot 2, soil of the selected farmland plus 3 % limestone (w/w) was applied and in pilot 3, soil of the selected farmland plus 3 % limestone was applied and then uncontaminated soil was covered thereon (0.3 m). After that, seeds of radish, Korean cabbage and soybean of which characteristics of edible portions are different were sowed on each plot and cultivated. Afterwards, at a proper harvesting time (app. 80 days later), crop plants and soil were collected and phytoavailability (0.11 M HOAc extractable) of heavy metals in soil and accumulated concentration of heavy metal in edible portion of crop plants were examined. As a result, it was revealed that phytoavailability of heavy metals in soil added with limestone (plot 2) was clearly reduced compared with plot 1 (untreated) and owing to this treatment, accumulated concentration of heavy metals in edible portion of crops was also clearly reduced compared with plot 1. While radish cultivated in plot 1 had exceeded maximum residue limit of agricultural products, in particular, plot 2 using limestone had shown concentration lower than maximum residue limit and this plot had shown little difference with 3 plot where crop was cultivated in uncontaminated soil cover. Therefore, it was considered that for abandoned farmland like the selected farmland, reducing mobility and phytoavailability of heavy metals and reducing crop uptake through stabilization method would be an effective and practical alternative for producing safe agricultural products on a sustained basis.

• Proceedings of the KSRS Conference
• /
• 2007.03a
• /
• pp.296-300
• /
• 2007

본 연구에서는 강원도 정선지역 및 삼척지역의 폐탄광 지역에서 관측된 지반침하지역의 공간자료와 각종 지반침하 관련요인을 분석하여, 지질학적구조와 지역적 특성이 상이한 지역에서 지반침하에 직접적인 영향을 주는 공통요인을 찾아내고자 하였다. 연구지역의 지반침하 관련요인들에 대해 GIS(Geographic Information System)를 이용하여 래스터 데이터베이스를 구축하고 모든 요인을 이용하여 분석한 위험지역과 하나의 요인씩 제거하며 분석한 위험지역을 비교하는 민감도 분석 (Sensitivity analysis)을 통해 지반침하와 연관성이 높은 요인을 추출하였다. 민감도 분석은 서로 다른 두 지역에 대해 수행하여 그 결과를 비교하였으며, 갱으로부터의 수평거리，RMR(Rock Mass Rating), 지하수 심도가 지반침하에 영향을 주는 공통요인으로 분석되었다. 본 연구결과, 폐탄광지역의 지반침하에 공통적으로 영향을 끼치는 주 요인을 구할 수 있었으며, 타 지역에서 지반침하 예측시 기존 연구에서 사용한 요인들의 데이터를 전부 구하지 못하는 경우에도 최소한의 필요한 요인을 정할 수 있으며 지반침하 예측의 효율성을 높일 수 있을 것이라 기대된다.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.7 no.1
• /
• pp.66-73
• /
• 2019

Approximately 80% of the mines are vacated or abandoned mines and are mostly left without suitable environmental treatment facilities. In the area around the abandoned mine site, problems such as drainage of acidic city drainage and leakage of leachate occur, and ground subsidence caused by this can cause a safety accident due to sink hole occurrence. In this study, flow, compressive strength, water uptake, pore and hydration characteristics were investigated to investigate the basic properties of liner and cover material based on the replacement ratio of nano silica and silica fume in the existing blast - furnace slag fine powder. As a result, as the substitution ratio of nano silica and silica fume increased, the flow and compressive strength of nano silica specimens increased and the absorption rate decreased. In the case of pore characteristics, the amount of pores decreased as the substitution ratio of nano silica and silica fume increased. Especially, the capillary porosity of 10-1,000 nm diameter decreased. Ray diffraction analysis and SEM measurement showed that the peak positions of the hydration products were almost the same when compared with the 5% alternative test samples of Plain and silica fume.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.5
• /
• pp.674-683
• /
• 2010

The current study was performed to examine the agricultural suitability of the cultivated upland nearby abandoned mining areas in Korea using three different scientific risk assessment models of Korea, USA and UK. For this, three mining sites DM, MG and KS were selected among 687 abandoned mines through preliminary risk assessment. A wide range of parameters were obtained through analysis of both soil and crop samples from the selected areas for heavy metal concentration and questionnaires to the communities along with the selected mining sites. Heavy metal concentration in soil samples was lower than the values previously reported by the Ministry of Environment (ME, 2002). However, both As and Cd concentration in the soil samples exceeded the concern level for agricultural area of the Soil Environment Conservation Act. Judging from the contaminant criteria for the crops, only Zn level in pepper, soybean and corn from the mining area DM exceeded the criteria whereas As, Cd, $Cr^{6+}$, Cu, Hg, Ni, Pb did not exceed the criteria. It was demonstrated that there would be human health risk by Pb accumulated in crops from both mining areas MG and KS when estimated by the risk assessment models of Korea and USA. Against it, results of the risk assessment model of UK showed human health risk by Pb in the crops from all study areas.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.04a
• /
• pp.167-174
• /
• 2004

Several metalliferous and coal mines, including Myungjin, Seojin and Okdong located at the upper watershed of Okdong stream, were abandoned or closed since 1988 due to the mining industry promotion policy and thus disposed an enormous amount of mining wastes without a proper treatment facilities, resulting in water pollution in the downstream areas. AMD and waste effluents from the closed coal mines were very strongly acidic showing pH ranges of 2.7 to 4.5 and had a high level of total dissolved solid (TDS) showing the ranges of 1,030 to 1,947 mg/L. Also heavy metal concentrations in these samples such as Fe, Cu, Cd and anion such as sulfate were very high. These parameters of AMD and effluents were considered to be highly polluted as compared to those in the main stream area of the Okdong river and be major pollutants for water and soil in tile downstream area. Pollution indices of the surface water at the upper stream of Okdong river where AMD of the abandoned coal mines was flowed into main stream were in the ranges of 16.3 to 47.1. On the other hand, those at the mid stream where effluents from tailing dams and coal mines flowed into main stream were in tile ranges of 10.6 to 19.5. However, those at the lower stream were ranged from 10.6 to 14.9 These results indicated that mining wastes such as AMD and effluents from the closed mines were tile major source to water pollution at the Okdong stream areas.

• Economic and Environmental Geology
• /
• v.41 no.1
• /
• pp.63-79
• /
• 2008

Physicochemical characteristics of stream water, leachate, mine water and groundwater were investigated to estimate the influences of the tailing and waste rock from the abandoned Uljin mine area. Total extraction analysis and mineralogical studies were carried out to understand sulfide weathering and to determine the distributions of trace elements in the soil affected by mine waste (tailing, waste rock and leachate). The pH and EC value of the leachate from the tailing disposal ranged 2.9-6.0, $99{\sim}3,990{\mu}S/cm$, respectively, and the concentrations of dissolved major (up to 492 mg/l Ca; 83.8 mg/l Mg; 45.2 mg/l Na; 44.7 mg/l K, 50.8 mg/l Si) and trace elements (up to $826,060{\mu}g/l$ Fe; $131,230{\mu}g/l$ Mn; $333,600{\mu}g/l$ Al; $61,340{\mu}g/l$ Zn; $2,530{\mu}g/l$ Cu; $573{\mu}g/l$ Cd; $476{\mu}g/l$ Pb) were relatively high. The stream water showed the variation of dissolved metal concentrations in seasonally and spatially. The dissolved metal contents of the stream water increased by influx the leachate from the tailing disposal, but these of the down stream have been considerably decreased by mixing of dilute tributaries. The dissolved metal concentrations of the stream water at dry season (as February) were lower than these at rainy season (as May and July). These represent that the amounts of the leachate varied with season. However, stream water could not be effectively diluted by confluence with uncontaminated tributaries, because the flux of tributaries and streams reduced at dry season. Thus attenuations by dilution had been dominantly happened in rainy seasons. The order of accumulations of trace element in soils compared with background values revealed Mn>Fe>Pb>Cu>Zn. Sulfide minerals were mainly pyrrhotite, sphalerite and galena and chalcopyrite. Pyrrhotite was rapidly weathered along the edge and fractures, and results in the formation of Fe-(oxy)hydroxides, which absorbed a little amount of Zn.