• Economic and Environmental Geology
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• v.40 no.4
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• pp.419-443
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• 2007

Recently, the branch-out of foreign companies into domestic markets through M&A and the opened followed by the Free Trade Agreement(FTA) with America have made the environmental site assessments of specific site more necessary. In this study, through case study of conducting actual environmental site assessment by use of a toolbox approach at a large scale of chemical plant with various contaminants located in a coastal area, the problems of guideline of domestic environmental assessment of soil were complemented. And an efficient and economical assessment was achieved. All six steps such as basic investigation, environmental site history survey, sampling and analysis, installation of monitoring wells and hydrogeological survey, and data interpretation were conducted in this study. All results of document survey, geological lineament analysis, field geology survey of surrounding area, geophysical prospecting of the site, hydraulic conductivity, measurement of groundwater flow rate and direction, sampling and analysis at each step were associated and estimated as an integrated tool box approach. As a consequence of this study, toolbox approaches were very useful techniques for contamination level and site characterization of subsurface media. The given conditions to conduct a basic survey for domestic soil environment assessment of site by use of existing documents, as well as interviews with the owner/manager/user of all adjacent properties and thorough review of all practically reviewable records pertaining to the property and surrounding properties within "Guideline for Soil Environment Assessment" radii are very poor. As a result, the application of toolbox approach in the environment site assessment of site is not only more efficient and economical, but also could be very useful assessment to integrate the soil and groundwater contamination.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.119-125
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• 2014

This study evaluated the environmental impacts of a soil washing (SW) process, especially, we compared the on-site and off-site remediation of TPH-contaminated soil using green and sustainable remediation (GSR) tool. To assess relative contribution of each stage on environmental footprints in the entire soil washing process, we classified the process into four major stages: site foundation (stage I), excavation (stage II), separation & washing (stage III), and wastewater treatment (stage IV). In on-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 87.1% and 80.4%, respectively in stage I, and in off-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 82.7% and 80.5%, respectively in stage II. In conclusion, the major factor contributing environmental impact in the SW process were consumable materials including steel and stainless steel for washing equipment in on-site treatment and fuel consumption for transportation of soil in off-site treatment.

• Journal of Soil and Groundwater Environment
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• v.8 no.4
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• pp.27-35
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• 2003

The study site located in an industrial complex has a Precambrian age gneiss as a bedrock. The poorly-developed, disturbed soils in the study site have loamy-textured surface soil (1 to 2 m) and gravelly sand alluvium subsurface (2 to 6 m) on the top of weathered gneiss bedrock. The depth of the groundwater table was about 3.5 m below ground surface and increased toward down-gradient of the site. The hydraulic conductivity of transmitted zone (gravelly coarse sand) was in the range of 5.0${\times}$10$\^$-2/∼1.85${\times}$10$\^$-1/ cm/sec. The fine sand layer was in the range of 1.5${\times}$10$\^$-3/ to 7.6${\times}$10$\^$-3/ cm/sec. and the reclaimed upper soil layer was less than 10$\^$-4/ cm/sec. Toluene, ethylbenzene, and xylene (TEX) was the major contaminant in the soil and groundwater. The average depth of the soil contamination was about 1.5 m in the gravelly sand alluvium layer. At the depth interval 2.4∼4.8 m, the highest contamination in the soil is located approximately 50 to 70 m from the suspected source areas. The concentration of TEX in the groundwater was highest in the suspected source area and a lesser concentration in the center and southwest parts of the site. The TEX distribution in the groundwater is associated with their distribution in the soil. Microbial isolation showed that Pseudomonas flurescence, Burkholderia cepacia, and Acinetobactor lwoffi were the dominant aerobic bacteria in the contaminated soils. The analytical results of the groundwater indicated that the concentrations of dissolved oxygen (DO), nitrate, and sulfate in the contaminated area were significantly lower than their concentrations in the none-contaminated control area. The results also indicated that groundwater at the contaminated area is under anaerobic condition and sulfate reduction is the predominant terminal electron accepting process. The total attenuation rate was 0.0017 day$\^$-1/ and the estimated first-order degradation rate constant (λ) was 0.0008 day$\^$-1/.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.283-286
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• 2002

유류로 오염된 부지에 토양세정기법을 적용하기 위한 전 단계로, 실험실 규모의 컬럼실험을 통하여 pilot 규모 현장 적용을 위한 설계인자 및 최적 운전조건을 규명하고자 적정 세척제 종류와 농도, 배합비 및 세정용액 주입유량을 고찰하였다. 회분식실험 결과 POE$_{14}$와 SDS(1:1)를 1%로 적용한 흔합계면활성제의 효율이 가장 우수하였으나, 예비실험 결과 음이온계 계면활성제인 SDS는 미생물에 독성을 끼치는 경향이 있는 것으로 나타나 같은 농도에서 효율이 거의 유사한 POE$_{5}$와 POE$_{14}$ 혼합계면활성제를 이용하여 실험하였다. 선정된 혼합계면활성제를 적용하여 디젤 오염토양 세척능력을 검토한 결과 세척제 농도 1%까지는 효율이 증가하다가 1% 이상의 농도에서는 다시 감소하는 경향을 나타내었으며, 계면활성제 배합비는 1:1로 혼합하였을 경우 세척효율이 가장 우수하였다. 따라서 POE$_{5}$와 POE$_{14}$ (1:1) 1% 혼합계면활성제를 세척제로 선정하였다. 컬럼실험 결과, 주입 flux가 클수록 세정 제거된 총 유류의 양이 증가하였으며, 같은 pore volume의 세정용액 통과 시에는 flux가 작을수록 제거효율이 좋았다.

• Journal of Soil and Groundwater Environment
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• v.9 no.3
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• pp.38-48
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• 2004

Natural attenuation of petroleum hydrocarbon was investigated at an industrial complex about 45 Km away from Seoul. The three-years monitoring results indicated that the concentrations of DO, nitrate, and sulfate in the contaminated area were significantly lower than the background monitoring groundwater under the non-contaminated area. The results also showed a higher ferrous iron concentration, a lower redox potential, and a higher (neutral) pH in the contaminated groundwater, suggesting that biodegradation of TEX(Toluene, Ethylbenzene, Xylene) is the major on-going process in the contaminated area. Groundwater in the contaminated area is anaerobic, and sulfate reduction is the dominant terminal electron accepting process in the area. The total attenuation rate was about 0.0017∼0.0224day$^{-1}$ and the estimated first-order degradation rate constant(λ) was 0.0008∼0.0106day$^{-1}$ . However, the reduction of TEX concentration in the groundwater was resulted from not only biodegradation but also dilution and reaeration through recharge of uncotaminated surface and groundwater. The natural attenuation was, therefore, found to be an effective, on-going remedial process at the site.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.310-313
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• 2000

본 연구에서는 현재 사용 종료된 매립지 재사용을 위해 정비를 실시 중인 전국 매립지 중에서 충남 공주시 금홍동에 위치한 사용 종료된 매립지를 대상으로 하여 사업 지구 및 그 주변지역의 환경질 평가를 위하여 토양에 관한 오염도 조사를 실시하였다. 시료는 매립지 내 1개 지점과 주변 논 2개 지점, 밭 1지점으로 총 4개 지점에서 채취하였다. 토양시료의 분석항목은 토양환경보전법에서 제시하는 총 11개 항목으로 하였으며, 실험방법은 토양오염공정시힘방법에 준하여 실시하였다. 실험결과 토양환경보전법상 농경지에 대한 우려기준과 비교하여 전 항목이 기준에 크게 미치지 못하는 것으로 나타났다. 토양질의 면에서 된다면 이 매립지 부지는 일반적인 용도의 토지로써 사용이 가능하다고 사료된다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.35-38
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• 2004

부틸알데히드로 오염된 대상 부지에 Biosparging 공법의 현장 적용을 위해 적정 공기 주입 압력 조건을 도출한 결과, 주 오염층인 자갈질 모래층에 공기주입 가능 파괴압력(Pe)는 약 300mmAq로 측정되었으며 4,500mmAq 압력 조건에서는 용존 산소농도의 영향 반경이 약 3 m로 나타났다. 위의 조건을 적용하여 약 150일간 운전한 결과, 영양물질을 투입하지 않은 초기 90일 동안 최고농도 대비 약 90%가 저감되었으며 그 이후에 영양물질을 투입하여 초기 최고 농도 대비 96%가 저감되어 복원목표치인 50ppm을 모든 지역에서 만족시켰다. 또한 생분해 반응속도가 k=0.03/day로 나타나 휘발성이 낮고 생분 해도가 뛰어난 부틸알데히드로 오염된 자갈질 모래층에 Biosparging공법이 성공적으로 적용된 사례이다.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.552-557
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• 2015

Ballast gravel in a railroad field is often polluted by grease and heavy metals. In this paper, the performances of a dry cleaning method for polluted ballast gravel in which pollutants on the gravel surface can be physically removed was extensively studied. A polluted ballast cleaning device able to shoot emery blasting media onto the surface using compressed air was prepared. Polluted ballast gravel was put into this device for cleaning, with the treatment time varied from 1 to 10 min. The cleaning efficiency of the total petroleum hydrocarbons and heavy metals were studied. The total petroleum hydrocarbon removal efficiency was 70-80% for gravels sampled from a locomotive waiting line, while it was 40-60% for gravels sampled from a turnout area. The heavy metal removal efficiency exceeded 90% for copper and lead, while it was 65-80% for nickel and zinc. This system was found to be effective for the remediation of polluted ballast gravels.

• Journal of the Korean Society of Radiology
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• v.16 no.2
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• pp.185-194
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• 2022

The decommission of nuclear legacy sites, which have been contaminated by previous activities such as uranium mining & milling as well as nuclear tests, has started to gain global attention. Within the Korean peninsula, Republic of Korea(ROK)has had experience in dismantling research reactors. For the Democratic People's Republic of Korea(DPRK), the possibility of nuclear activities being implemented and operations records being managed without consideration of the latest nuclear safety regulations are high. Hence, the chances of DPRK's sites remaining as nuclear legacy is also high. This study investigates approaches and considerations that needs to be taken in account in the event of a nuclear legacy site occurrence, reviewing its international cases for the solution of the legacy sites. The regulation, process of optimization, and stakeholder engagement for a nuclear legacy site should be considered in such an event. Developing legacy site response plans can be used to prevent future legacy site occurrences.

• Spatial Information Research
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• v.20 no.4
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• pp.17-27
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• 2012

This study was performed to evaluate the spatial distribution of heavy metals using principal component analysis and Ordinary Kriging technique in the Gangwon Mine site. In the soils from the sub soil, the contents of Zn and Ni in the PC1 were gradually dispersed from south to north direction, while the components of Cd and Hg in the PC2 showed an increase significantly from middle-south area in the Gangwon Mine site. According to the cluster analysis, pollutant metals of As and Cu were presented a strong spatial autocorrelation structure in cluster D. The concentration of As was 0.83mg/kg and shown to increase from the south to north direction. The spatial distribution maps of the soil components using geostatistical method might be important in future soil remediation studies and help decision-makers assess the potential health risk affects of the abandoned mining sites.