• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.122-122
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• 2005

The remediation for contaminated soil and groundwater in contaminated site and waste site has to be compact and economic in maintaining and operating the system. In this study, the atomized slag was tested if they are an effective reactive material in permeable reactive barrier This novel reactive system technology was applied to the treatment of leachate from unplanned waste landfill. The system was optimized and developed to be commercialized.

• 한국습지학회지
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• 제24권2호
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• pp.142-154
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• 2022

지하수의 비소(As) 오염은 방글라데시의 주요 문제 중 하나이다. 독성은 부종, 피부암, 방광암, 폐암, 각화 과다증, 조산, 흑사병과 같은 심각한 건강 문제를 야기한다. 지하수의 오염은 주로 인위적 활동의 영향을 받는 지역의 지질학적 특성에서 발생된다. 방글라데시 국민의 대부분이 지하수에 식수를 의존하고 있기에 비소 오염 현황을 조사하고 물이 부족한 지역에 안전한 식수를 제공하기 위하여 비소 처리를 위한 수처리 기술이 필요하다. 따라서 본 연구는 92개의 논문을 기반으로 방글라데시의 지하수 As 오염 관련 최근 현황과 다양한 저비용 정화 기술에 대한 트렌드를 조사하였다. 방글라데시에서 지하수 비소 오염이 가장 높은 지역은 Brahamanbariya, Tangail, Barisal, Pabna, Patuakhali 및 Kurigram등 총 4곳이며, Magura 및 Faridpur 등의 지역에서는 비소 농도가 0.05mg/L를 초과한다. WHO 표준 가이드라인 값(<0.01 mg/L)을 만족하는 지역은 Kushtia, Khagrachari, Jessore, Dinajpur, Meherpur 및 Munshiganj 등 총 6곳으로 나타났다. 수중에서 As를 처리하는 기술이 다양하다. 시간-비용효율적인 처리 방법은 Mg-Fe계 Hydrotalcite와 유사 화합물, electro-chemical As remediation (ECAR) reactor, aerated electrocoagulation 등이 적용되고 있다. 전반적으로 예산, 운영 및 유지 관리 비용, 재료의 가용성 및 전문 지식 요구 사항 등을 고려하여 수질 내 비소를 처리해야 한다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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• pp.69-81
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• 2012

Diverse geostatistical tools such as kriging have been used to estimate the volume and spatial coverage of contaminated soil needed for remediation. However, many approaches frequently yield estimation errors, due to inherent geostatistical uncertainties. Such errors may yield over- or under-estimation of the amounts of polluted soils, which cause an over-estimation of remediation cost as well as an incomplete clean-up of a contaminated land. Therefore, it is very important to use a better estimation tool considering uncertainties arising from incomplete field investigation (i.e., contamination survey) and mathematical spatial estimation. In the current work, as better estimation tools we propose stochastic simulation approaches which allow the remediation volume to be assessed more accurately along with uncertainty estimation. To test the efficiency of proposed methods, heavy metals (esp., Pb) contaminated soil of a shooting range area was selected. In addition, we suggest a quantitative method to delineate the confident interval of estimated volume (and spatial extent) of polluted soil based on the spatial aspect of uncertainty. The methods proposed in this work can improve a better decision making on soil remediation.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.72-79
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• 2016

Bioremediation is one of the most effective ways to remediate TPH-contaminated sites. However, under actual field conditions that are not at the optimum temperature, degradation of microorganisms is generally reduced, which is why the efficiency of biodegradation is known to be significantly affected by the soil temperature. Therefore, in this study, the labscale experiment was conducted using indigenous crude oil degrading microorganisms isolated from crude oil contaminated site to evaluate the remediation efficiency. Crude oil degrading microorganisms were isolated from crude oil contaminated soil and temperature, which is a significant factor affecting the remediation efficiency of land farming, was adjusted to evaluate the microbial crude oil degrading ability, degradation time, and remediation efficiency. In order to assess the field applicability, the remediation efficiency was evaluated using crude oil contaminated soil (average TPH concentration of 10,000 mg/kg or more) from the OO premises. Followed by the application of microorganisms at 30℃, the bioremediation process reduced its initial TPH concentration of 10,812 mg/kg down to 1,890 mg/kg in 56 days, which was about an 83% remediation efficiency. By analyzing the correlation among the total number of cells, the number of effective cells, and TPH concentration, it was found that the number of effective microorganisms drastically increased during the period from 10 to 20 days while there was a sharp decrease in TPH concentration. Therefore, we confirmed the applicability of land farming with isolated microorganisms consortium to crude oil contaminated site, which is also expected to be applicable to bioremediation of other recalcitrant materials.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권3호
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• pp.37-49
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• 2021

There is domestic Soil Contamination Warning Standard (SCWS) as remediation standard concentration of contaminated soils. No risk should be observed at soil concentration less than SCWS. Therefore, SCWS was evaluated to confirm the risk assessment. Background Concentration of Soil (BGC) and target remediation concentration were also assessed. The results show that Excess Cancer Risk (ECR) of SCWS was the highest in the groundwater intake pathway (Adult: 6.27E-04, Child: 2.81E-04). Total Cancer Risk (TCR) was 7.76E-04 and 4.30E-04 for adult and child, exceeding reference value (10^-6). Hazard Quotient (Non-Carcinogenic Risk, HQ) was the highest in the indoor air inhalation pathway (Adult: 3.64E+03, Child: 8.74E+02). Hazard Index (Total Non-Carcinogenic Risk, HI) exceeded reference value 1. ECR of the BGC was the highest in the groundwater intake pathway (Adult: 1.71E-04, Child: 7.67E-05). TCR was 2.12E-04 for adults and 1.17E-04 for children, exceeding the reference value (10^-6). HQ was the highest in groundwater intake pathway (Adult: 4.10E-01, Child: 1.84E-01). HI was lower than reference value 1 (Adult: 4.78E-01, Child: 2.50E-01). The heavy metal affecting ECR was Arsenic (As). The remediation-concentration of As was 7.14 mg/kg which is higher than BGC (6.83 mg/kg). TCR of As should be less than reference value (10^-6), but it was higher for all of SCWS, BGC and target remediation concentration. Therefore, it is suggested that risk assessment factors should be re-evaluated to fit domestic environmental settings and SCWS should be induced to satisfy the risk assessment.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.13-22
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• 2015

In this study, we have developed the performance evaluation model for the optimal soil remediation technology selection. Performance evaluation model is composed in the evaluation of two steps. In the first stage, the candidate technologies are derived according to the conditions of drilling, type and concentration of pollutants, and the saturated/unsaturated of target site. In the second stage, each individual candidate technology is evaluated by performance evaluation model. The performance evaluation model has 5 groups of evaluation items and 12 evaluation items which have their own evaluation index and their own weights through the AHP approach surveying 40 experts. From the case study of actual design cases, the applicability of the performance evaluation model was confirmed.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권2호
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• pp.34-39
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• 2010

In this study, the remediation of diesel contaminated soil was attempted with ozone treatment and Fenton reaction. About 10% of initial diesel concentration was removed by the ozone saturated solution. The pseudo-first order decomposition constant of diesel contaminated soil in the presence of 5% of hydrogen peroxide with 1.82, 2.82, 4.82, 6.82, and 11.82% of iron contents was 0.0228, 0.0308, 0.0482, 0.0471, and 0.0592 $min^{-1}$ respectively. The decomposition constant of the diesel was 0.0064 $min^{-1}$ with the addition of ozone saturated solution only. On the addition of ozone saturated solution in the presence of 5% hydrogen peroxide and 5% iron, the decomposition constant of the diesel was 0.0850 $min^{-1}$. These results indicated that the decomposition rate was 190% faster than without the addition of ozone saturated solution. Thus, the application of both ozone and the fenton reaction is promising for the remediation of the diesel contaminated soil.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.53-63
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• 2010

Pneumatic fracturing is an emerging tool to enhance the remediation efficiency of contaminated unsaturated zones by injecting high pressure air and inducing artificial fracture networks. Pneumatic fracturing is reported to be well suited for the cases where the contaminated unsaturated zone thickness is less than 5 m as many contaminated domestic sites in Korea. Nevertheless, there have been almost no studies carried out on the site-specific efficiency and the optimized design of pneumatic fracturing considering the unsaturated zone characteristics of Korea. In this study, we employ numerical simulations to compare the efficiency of pneumatic fracturing on the aspect of the site remediation and the porosity improvement at several hypothetic unsaturated zones composed of four typical soil types. According to the simulation results, it is found that the zone with fine grains soil such as clay and silt shows better efficiency than the zone composed of coarse grains in terms of air flow and porosity enhancements. The results imply that pneumatic fracturing may improve the efficiency of site reclamation by jointly or independently applied to the many contaminated sites in Korea.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1400-1407
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• 2005

There are a number of approaches to in situ remediation that are used at contaminated sites for removing contaminants from the contaminated zone without excavating the soil. These include soil flushing, dual phase extraction, and soil vapor extraction. Of these techniques, soil flushing is the focus of the investigation in this paper. The concept of using prefabricated vertical drains(PVDs) for remediation of contaminated sites with fine-grained soils is examined. The PVD system is used to shorten the drainage path or the groundwater flow and promote subsurface liquid movement expediting the soil flushing process. The use of PVDs in the current state of practice has been limited to soil improvement. The use of PVDs under vacuum conditions is investigated using sample soil consisting of silty sand.

• Journal of Ecology and Environment
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• 제42권4호
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• pp.191-198
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• 2018

Improper management and unsanitary approaches are implemented in disposal of leachate, which has resulted in groundwater pollution at village Uruli Devachi, Pune, India. Various physico-chemical treatment methods are commercially available for leachate treatment. However, the application of biological methods viz. phytoremediation to the municipal solid waste landfill leachate has been limited. We report the remediation ability of Typha aungstifolia and Acrorus calamus that is capable of reducing hazardous constituents from the landfill leachate. After 96 h of hydraulic retention time (HRT), it was observed that T. aungstifolia-treated sample showed high reduction potential in reducing biochemical oxygen demand, chemical oxygen demand, hardness, total dissolved solids, Na, Mg, Ca and Ni whereas A. calamus showed greater reduction capacity for alkalinity, Cl, Cu, Zn and Cr. Furthermore, it was also observed that T. aungstifolia withstood longer HRT than A. calamus. In situ application of T. aungstifolia and A. calamus for remediation of landfill leachate carries a tremendous potential that needs to be further explored.