• 한국지하수토양환경학회지:지하수토양환경
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• 제27권spc호
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• pp.99-112
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• 2022

From early 2000, many researchers in the groundwater and soil environment remediation project tried to calculate the pollution level and pollution remediation cost and reflect it in the design. In addition, by identifying the movement characteristics of oil pollutants in the underground environment, many researchers tried to derive design factors necessary for pollution purification. However, although the test should be conducted in an area contaminated with oil, the toxicity and risk are too great for testing by deliberately leaking pollutants that are harmful to the human body. And as oil-contaminated areas are promoted by military units such as returned US military bases, there is a limit to access by the general public. In addition, since the indoor simulation test and the field application test have been carried out separately from each other, it was difficult to compare and review various simulation tests Therefore, in this study, PITT (Partitioning Interwell Tracer Test) and analysis methods were specifically presented through actual tests so that field workers could easily use them with the help of the military base and the Korea Rural Community Corporation Soil Environment Restoration Team. However, in order to directly reflect the distribution tracer test results in the pollution remediation design, it is necessary to reduce the analysis errors by comparing the analysis results of the existing soil pollution survey, physical exploration, and numerical modeling. In addition, it is judged to be cautious in the analysis because errors can easily occur due to various factors such as the type of oil at the polluted site, the hydraulic conductivity of the aquifer, and the skill of the researcher.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.67-77
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• 2013

To improve the energy efficiency of conventional thermal treatment, soil remediation with microwave has been studied. In this study, the remediation efficiency of contaminated soil with semi-volatile organic contaminants were evaluated with microwave oven and several additives such as water, formic acid, iron powder, sodium hydroxide (NaOH) solution, and activated carbon. For the experiment, loamy sand and sandy loam collected from Imjin river flood plain were intentionally contaminated with hexachlorobenzene and phenanthrene, respectively. The contaminated soils were treated with microwave facility and the mass removals of organic contaminants from soils were evaluated. Among additives that were added to increase the remediation efficiency, activated carbon and NaOH solution were more effective than water, iron powder, and formic acid. When 10 g of hexachlorobenzene (142.4 mg/kg-soil) or phenanthrene (2,138.8 mg/kg-soil) contaminated soil that mixed with 0.5 g iron powder, 0.5 g activated carbon and 1 ml 6.25 M NaOH solution were treated with microwave for 3 minutes, more than 95% of contaminants were removed. The degradation of hexachlorobenzene during microwave treatments with additives was confirmed by the detection of pentachlorobenzene and tetrachlorobenzene. Naphthalene and phenol were also detected as degradation products of phenanthrene during microwave treatment with additives. The results showed that adding a suitable amount of additives for microwave treatments fairly increased the efficiency of removing semi-volatile soil organic contaminants.

• 한국지하수토양환경학회지:지하수토양환경
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• 제6권2호
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• pp.23-30
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• 2001

본 주상실험은 오염된 토양에서의 계면활성제 용액상태에 따른 복원 효과를 조사하기 위하여 실행되었다. 농도, pH, 온도, 그리고 용액의 유속을 달리하여 실험을 수행하였다. 실험에 사용된 오염물질은 톨루엔, 토양시료는 Iowa Fruitfield sandy soil, 그리고 계면활성제는 Sodium diphenyl oxide disulfonate (DOSL)이었다. 실험결과, 최적 조건은 다음과 같이 구해졌다. 계면활성제의 농도는 4 %(v/v), pH는 10, 온도는 $20^{\circ}C$, 그리고 유속은 4 mL/min이었다. 이 조건이 모두 만족하는 상태에서는 95 %의 톨루엔이 제거되었으며 이는 다른 조건에서보다 6~l9 %의 상승효과를 보인 것이다. 본 실험에서 보여준 계면활성제 조건은 톨루엔으로 오염된 대수층의 복원에 매우 유용한 자료가 될 것이다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권6호
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• pp.17-22
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• 2008

산순환 동전기적 정화기술의 아연과 니켈로 오염된 토양의 정화 타당성을 조사하였다. 1M HCl을 활용한 토양세척에서 아연과 니켈의 제거율은 각각 24%와 9%였으며, 산세척은 이 토양을 정화하기에 적합하지 않았다. 일반적인 동전기 정화 방법으로 28일 동안 운전한 결과, 아연과 니켈의 제거율은 산세척보다도 낮았다. 강산으로 음극을 순환시켜주어 토양 전체의 pH를 산성으로 조절한 실험에서 아연과 니켈의 제거는 비약적으로 증가하였다. 또한 강산으로 전처리한 토양에서는 그 제거율이 보다 많이 증가하였다. 이러한 실험결과를 근거로 볼 때 산순환 동전기 정화는 아연과 니켈로 오염된 토양을 정화하는데 매우 효과적인 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권5호
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• pp.35-44
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• 2014

In this study, the bio-phytoremediation and phytoremediation technologies were applied to the soils contaminated with total petroleum hydrocarbons (TPH) and heavy metals to evaluate the remediation efficacy from May 2012 to December 2013. Poplar (Populus bonatii Levl.) and Sun Hemp (Crotalaria juncea L.) were selected and planted in phytoremediation practice. These plants were also utilized in the bio-phytoremediation practice, with the addition of earthworm (Eisenia fetida) and petroleum-degrading bacteria (Pseudomonos sp. NKNU01). Furthermore, physiological characteristics, such as photosynthesis rate and maximal photochemical yield, of all testing plants were also measured in order to assess their health conditions and tolerance levels in adverse environment. After 20 months of remedial practice, the results showed that bio-phytoremediation practice had a higher rate of TPH removal efficacy at 30-60 cm depth soil than that of phytoremediation. However, inconsistent results were discovered while analyzing the soil at 100 cm depth. The study also showed that the removal efficiency of heavy metals was lower than that of TPH after remediation treatment. The results from test field tissue sample analysis revealed that more Zinc than Chromium was absorbed and accumulated by the tested plants. Plant height measurements of Poplar and Sun Hemp showed that there were insignificant differences of growth between the plants in remediation plots and those in the control plot. Physiological data of Poplar also suggested it has higher tolerance level toward the contaminated soils. These results indicated that the two testing plants were healthy and suitable for this remediation study.

• 한국해안·해양공학회논문집
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• 제27권1호
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• pp.9-13
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• 2015

본 연구에서는 일본 히로시마시 텐마강 하구에 위치한 점토질 갯벌을 대상으로 투수성이 높은 다공질 파일을 설치하여 갯벌 내부에서의 지하수 흐름 형성여부를 확인하고 그에 따른 저질의 성상변화를 조사하였다. 하천의 수위가 변할 때 하천수가 다공질 파일의 하부 및 상부를 통해 공급되면서 갯벌 내부에서 지하수의 흐름이 형성되는 것이 확인되었다. 지하수의 흐름을 통해 다공질 파일내의 DO 농도가 최대 4 mg/L까지 증가하였다. 다공질 파일 내부의 DO 농도의 증가는 저질내의 환원물질과 유기물량을 감소시키는데 효과적이었으며, 지하수의 흐름은 퇴적된 점토질 입자의 재부상을 촉진시키는 것으로 조사되었다. 이상의 결과로부터 점토질 갯벌 내에 다공질 파일을 설치함으로써 점토질 갯벌의 저질 환경을 효과적으로 개선할 수 있음을 확인하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권2호
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• pp.1-9
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• 2013

The landfarming treatment for the remediation of the petroleum contaminated soil at the returned U.S. Military bases was investigated in this study. Specifically, the bioaugmentation performance using various commercially available petroleum-degrading bacteria was evaluated and the directions for enhancing the performance of the landfarming treatment were suggested. The environmental factors of the soils at the returned U.S. Military bases chosen for remediation indicate that the landfarming treatment can be used as the remediation technique; however, the addition of nitrogen or phosphorus is required. The lab-scale landfarming treatment tests using the model soil and the site soil showed that the degradation efficiency was greater with the model soil than the site soil and that the treatment performance was not affected by the number of bacteria present in the soil in the range of $10^6-10^{12}$ CFU/g. These results suggest that the successful landfarming treatment depends on the petroleum degradability of bacteria used and the environmental conditions during the treatment rather than the number of petroleum-degrading bacteria used.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 International Symposium
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• pp.70-86
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• 2003

Despite its usability, TCE has been managed as a hazardous material due to the toxicity and many contamination cases were surveyed in some developed countries. U.S.EPA(Kram et al., 2001) suggested DNAPL characterization methods and approaches based on survey experiences at several sites. However, Korea has not the least assessment of contamination and trial of remediation, although there are a lot of doubtable areas where ground water would be contaminated with TCE. In this study, we try to assess the volume and extent of ground water contamination with TCE and delineate the contamination source zones in an industrial area. Ground water in this area flows through fractures and the contaminant TCE has the properties of high volatility, high density and low partitioning to soil material. Thus, we applied a variety of technical approaches to identify the contamination status; documentary, hydrogeochemical, hydrogeological and geological surveys. In addition, additional survey was performed based on the interim findings, which showed that ground water contamination was limited to the relatively small area with high concentrations to the deep place. The contamination source zone is estimated to be the asphalt test institute where a great deal of TCE has been used to analyze the amount of asphalt soluble in TCE since 1984. Based on the contamination characterization and a myriad of documents about ground water remediation, appropriate site remediation management options will be recommended later. This study is now under way and this paper was focused on describing the technical approaches used to achieve the goals of this study.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.48-56
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• 2017

Although various methods have been investigated for treatment of crude oil contaminated soil, more researches are still required to preserve soil environment. This study investigated the potential utility of subcritical water in remediation of crude oil contaminated soil under various experimental conditions including temperature ($150-300^{\circ}C$), flow rate (1.0-2.0 mL/min) and extraction time (60-120 min). The removal rate of crude oil gradually increased with increasing temperature and time. After treatment at $200^{\circ}C$ and $300^{\circ}C$ for 60 min, the remaining concentration of crude oil met the Kuwait standard clean-up level (10,000 mg/kg) and the Korean standard level (2,000 mg/kg), respectively. The removal efficiency of crude oil increased from 77.8% to 88.4% with increasing extraction time from 60 to 120 min at $250^{\circ}C$. A decreasing rate of oil removal was observed as flow rate increased, possibly due to channeling flow occurred within the soil body at higher flow rate condition. Overall, the results revealed that subcritical water extraction process could be feasible for remediation of crude oil contaminated soil, and the relative effect of parameters on the oil removal was in the order of temperature > time > flow rate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권4호
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• pp.36-43
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• 2012

Various methods are used to remediate soil contaminated with heavy metals or petroleum. In recent years, harsh physical and chemical remediation methods are being used to increase remediation efficiency, however, such processes could affect soil properties and degrade the ecological functions of the soil. Effects of soil washing, thermal desorption, and land farming, which are the most frequently used remediation methods, on the physicochemical properties of remediated soil were investigated in this study. For soils smaller than 2 mm, the soil texture were changed from sandy clay loam to sandy loam because of the decrease in the clay content after soil washing, and from loamy sand to sandy loam because of the decrease in the sand content and increase in silt content during thermal desorption, however, the soil texture remained unchanged after land farming process. The water-holding capacity, organic matter content, and total nitrogen concentration of the tested soil decreased after soil washing. A change in soil color and an increase in the available phosphate concentration were observed after thermal desorption. Exchangeable cations, total nitrogen, and available phosphate concentration were found to decrease after land farming; these components were probably used by microorganisms during as well as after the land farming process because microbial processes remain active even after land farming. A study of these changes can provide information useful for the reuse of remediated soil. However, it is insufficient to assess only soil physicochemical properties from the viewpoint of the reuse of remediated soil. Potential risks and ecological functions of remediated soil should also be considered to realize sustainable soil use.