• Journal of the Korean Society for Railway
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• v.3 no.3
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• pp.101-108
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• 2000

In this study, we tested hybrid pilot system combined with soil vapor extraction and bioventing methods on the contaminated railroad soil. So, we found out the remediability and operating conditions. Air permeability(k) and gas phase(O$_2$/CO$_2$/VOCs) level trend are very important to determine the remediation rate of the contaminated sites. Throughout hybrid pilot test on different conditions, the range of air permeability(k) was 1985∼1194 darcy. The tests results in hybrid system was appropriate on this test sites, and the suitable injection air flow rate was 3.5㎥/hr. So, we suggested a basic data for the remediation and management of contaminated railroad soil.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.1-35
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• 2007

In the last decades, the decrease in biological or chemical availability of sorbed contaminants as contact time passed, is generally accepted. This phenomenon so called as "aging" or "sequestration" is known to directly affect risk of the contaminats. This was observed for mainly for hydrophobic organic contaminants (HOCs), but also reported for heavy metals. Aging is known to be directly related to sorption-desorption hysteresis, irreversible sorption, desorption-resistance, nonequilibrium sorption, etc. The decrease in bioavailability due to aging or sequestration indicates realistic decrease in risk potential. Recently a risk-based management concept by scientific evidences but not the simple measurement of contaminant concentration has been attempted to determine environmentally acceptable remedial endpoint. This is because selection of remedial endpoint based on not total concentration but the bioavailability and toxicity of contaminants can reduce both the treatment cost and remedial activities of the contaminated sites. The bioavailability and toxicity of the residual contaminants are highly affected by the fate and transport and also directly affect the exposure pathways and bioaccumulation of contaminants in the living biota. In this paper, scientific feasibility on the risk-based clean-up and management of contaminated sites is reviewed.

• 한국생물공학회:학술대회논문집
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• 2004.07a
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• pp.107-125
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• 2004

A bioremediation of petroleum-contaminated soil in Korea was evaluated for the optimization of enhanced biodegradation and the minimization of effects of seasonal variations, The short-term bioremediation in combination of biopile pretreatment and landfarming was performed by lowering contaminated levels and overcoming the inhibiting factors in the rainy and winter seasons. A microbial density was maintained with indigenous microbial addition for bioaugmentation and with fertilizers for biostimulation. A lesser volatile and biodegradable fraction due to their abiotic removals following the biopile pretreatment was effectively removed by the laterally applied landfarming. The optimal temperature in greenhouse was maintained by buffering of the soil temperature even with slight decreases in removal rates during the winter and extensive leaching of nutrients and contaminants was restricted with adjusting the water contents during the Korean rainy season. Although the tilling process was effective for biodegradation with aeration only, the simultaneous treatment due to apparent mixing of nutrients and microbes more favorably degraded the petroleum than the sequential treatment.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.287-290
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• 2002

계면활성제를 이용한 유류 오염토양 복원기술 적용시 발생되는 세척 유출수를 유류분해 미생물로 알려진 Pseudomonas putida Fl, Pseudomonas oleovorans, Acinetobacter calcoaceticus를 이용하여 생물학적으로 처리하는데 필요한 기초 연구를 실시하였다 세종류의 미생물은 본 연구에 사용된 계면활성제(POE$_{5}$, POE$_{14}$)에 대하여 독성이 없는 것으로 판명되었으며, 배양 종료 후 계면활성제 농도에 따른 TPH 분해율은 0.1%, 0.5%, 1%의 계면활성제 농도에서 유사한 분해율을 나타냈으나, 배양 초기에는 0.1%가 0.5%나 1% 농도에 비하여 높은 분해율을 보였다 pH의 변화에 따른 TPH 분해율은 적용 pH 범위(4, 6.5, 9)내에서 모두 생육이 가능하였으며, 세 종류의 미생물은 pH 6.5에서 가장 높은 TPH 분해 율을 나타내었다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.167-170
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• 2000

The purpose of study is to evaluate the effects of physical parameters on diesel biodegradation in diesel contaminated soil. The parameters applied are concentration, temperature, moisture contents, electron acceptor(O$_2$). The results of this study showed that diesel were degraded faster at high temperature and moisture contents than at low temperature and moisture content. However concentration effect study indicates that diesel were more faster degraded at low concentration than at high concentration. The results of electron acceptor test showed concentration of oxygen did not affect the biodegradation rate of diesel in oxygen condition(10, 20%) of this study.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.323-332
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• 2003

This study was carried out to provide information for the present status of soil pollution near abandoned old-zinc mining area through analysis of bound form and 0.1 N-HCl extractable concentrations of heavy metals in soils and plants. Feasibility of endemic plants for phytoremediation was evaluated by the investigation of vegetation in soils. Cd contents of the selected samples near old-zinc mining soils ranged from 0.2 to $42mg\;kg^{-1}$. Nonagricultural soils near the mining area contained great amounts of Zn, Pb, Cd, and Cu than the paddy and upland soils. Some Korean wild plants, Artemisia princeps, Artemisia montana, Erigeron canadensis, and Pueraria thunbergiana, were found to grow vigorously in the studied area. Among them, Artemisia princeps was selected as a possible phytoremediator for cleaning heavy metal contaminated soils. Artemisia princeps contained about 43 and $52mg\;kg^{-1}$ of Cd in their root and shoot as dry weight, respectively. Average contents of Cd in the rhizosphere soil, $15.68mg\;kg^{-1}$, was slightly higher than the soil-root interface soils, $14.1mg\;kg^{-1}$. Sequential extraction of Cd contaminated soils showed that average $2.4mg\;kg^{-1}$ (about 7%) of cadmium existed as exchangeable form and the average amounts increased as follows : adsorbed < organically bound < exchangeable << oxide carbonate << sulfide residual fractions. Amendment of organic by-product fertilizer in metal-contaminated soils promoted the growth of roots significantly as compared with the other treatments containing chemical fertilizer.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.1
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• pp.77-82
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• 2000

Seven constructed and three natural tidal flats were compared to evaluate state-of- the-art of creation and restoration technology for tidal flats. parameters studied were physico-chemical and biological characteristics of soils and rate of respiration. The natural tidal flats had higher contents of silts, nitrogen and organic matter compared to the constructed ones. The natural ones had reductive Bone below 2 cm whereas the constructed ones had oxidative zone from the surface to below 20 cm. The bacterial population in the soil of the constructed tidal flats was one to two magnitudes lower than that in the natural ones. Biomass of macrobenthos and microbial respiration rate, however, were not different significantly between the natural and the constructed tidal flats. The purification capacity by diatom+bacterial+meiobenthos and macrobenthos in the constructed tidal flats was higher than that in the natural ones due to deeper permeable layer for purification in the constructed tidal flats. There was an exceptional constructed tidal flat with similar physico-chemical and biological characteristics to natural ones. Shearing stress to the surface of the tidal flat by the flow of seawater was as low as that of natural ones. These hydraulic conditions seemed to be a controlling factor on structures and functions of tidal flats. The control of hydraulic condition seemed to be one of the most important factors to create natural-like tidal flats.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.721-730
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• 2006

The effects of compost amendment on the removal of petroleum hydrocarbons and the activities of microorganisms in soil ecosystem have been studied in bioremediation of diesel contaminated soil. The relation between biological activities and removal of petroleun hydrocarbon was determined by ATP(Adenisine Triphosphate), n-alkanes and TPH concentration analysis. After 80 days of bioremediation, the removal of TPH in soil amended with compost increased more than 10% compared with control soil which was tilled in the same condition without compost addition. The biodegradations of n-alkanes having 12 to 20 moles of carbon were distinctive. As the soil was contaminated with more diesel, the ATP has decreased rapidly. When the TPH amounted to 80,000 mg diesel/kg, the ATP decreased to 4 ng/g from initial concentration of 65 ng/g. While the ATP in the compost amended soil increased to 112 ng/g after tilling for 6 days, the ATP in the control increased to merely 36 ng/g after tilling for 14 days. Also while the control soil showed a lag time in ATP increase, the compost amended soil did not show that but showed a rapid ATP increase within a short time. The patterns of changes in ATP concentration were similar to those in daily removals of TPH with time difference of about 7 days.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.83-93
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• 2006

In heavily industrialized areas, soil sites are contaminated with high concentrations of heavy metals. These pollutants are highly accumulated to the human body through the food web and cause serious diseases. To remove heavy metals from the soil, a potential strategy is the environmental friendly and cost effective phytoremediation. For the enhancement of remediation efficiency, the symbiotic interaction between the plant and plant growth-promoting rhizobacteria (PGPR) has been attended. In this review, the interaction of the plant and PGPR in the heavy metal-contaminated soil has been reviewed. The physicochemical and biological characteristics of the rhlzosphere can influence directly or indirectly on the biomass, activity and population structure of the rhizobacteria. The root exudates are offered to the soil microbes as useful carbon sources and growth factors, so the growth and metabolism of rhizobacteria can be promoted. PGPR have many roles to lower the level of growth-inhibiting stress ethylene within the plant, and also to provide iron and phosphorus from the soil to plant, and to produce phytohormone such as indole acetic acid. The plant with PGPR can grow better in the heavy metal contaminated soil. Therefore higher efficiency of the phytoremediation will be expected by the application of the PGPR.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.298-301
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• 2003

생물학적 토양오염 복원기술은 산소와 영양염류를 오염토양에 공급하여 호기성 미생물의 대사작용을 자극함으로써 유류를 생분해 하는 방법으로 널리 사용되고 있다. 유류에 오염된 토양은 혐기성 상태인 경우가 대부분이기 때문에, 호기성 미생물을 이용하기 위해서는 충분한 산소를 공급하여야 하므로 운전비가 많이 드는 단점이 있다. 최근에는 혐기성 미생물을 이용하여 유류오염 토양을 정화하는 방법이 보고되고 있다. 혐기성 생분해 방법은 다소 분해 속도는 느리지만 산소를 공급하지 않기 때문에 경제적인 유류오염토양 복원 방법으로 주목받고 있다. 본 연구에서는 디젤을 사용하여 인위적으로 10000 mg/kg.TPH soil의 농도로 오염시킨 토양 50g을 100$m\ell$ 용적의 vial에 주입하고 하수처리장의 혐기성 소화조 슬러지를 15$m\ell$, 30$m\ell$을 주입하여 배양하였으며 TPH의 분해량과 CH$_4$ 및 $CO_2$ 발생량을 측정하였다. vial의 기상을 $N_2$가스로 치환함으로써 혐기성 상태가 되도록 하였으며, 35$^{\circ}C$에서 90일간 배양하였다. 그 결과, 슬러지를 주입하지 않은 대조군의 경우에는 TPH의 분해가 거의 없었지만, 슬러지를 주입한 경우에는 TPH(Total Petroleum Hydrocarbon)농도가 55% 제거된 것으로 나타났다. TPH의 분해는 CH$_4$ 및 $CO_2$ 발생량과 밀접한 상관관계를 보였다. 본 연구의 결과로부터 하수처리장의 혐기성 소화조 슬러지를 이용한 유류오염 토양의 복원 가능성을 확인할 수 있었다.양에서 유동 가능성이 있는 중금속만을 추출하였다. 분석실험은 토양의 Cd2+ 와 Pb2+를 대상으로 행하여졌으며, 여러 토양에서 추출 분석한 결과를 EDTA분석결과와 비교하였다. 실험결과, 중금속은 매우 신속하게 고분자 자성체와 결합하였고, 그 후 자성체를 외부 자장으로 모은 후 산으로 용해시키고, 결합된 중금속은 Graphite furnace AAS로 분석함으로써 빠르고 효율적으로 분석실험을 수행할 수 있음을 알 수 있었다. 한편, 실험에서 나타난 수치들을 비교 검토한 결과 토양 분석시 sandy soil에서는 자성체를 이용한 분석이 EDTA에 의한 방법보다 더 높은 추출도를 보인 반면, silt 함량이 많은 토양의 경우에서 EDTA분석에서 더 높은 중금속 추출도를 보였다.s 중에서 490nm와 555nm의 복합밴드를 포함하는 OC2 알고리즘(ocean color chlorophyll 2 algorithm)을 사용하는 것이 OC2 series 및 OC4 알고리즘보다 좋은 추정 값을 도출할 수 있을 것으로 기대된다.환경에서는 5일에서 7월에 주로 이 충체의 유충이 발육되고 전파되는 것으로 추측되었다.러 가지 방법들을 적극 적용하여 금후 검토해볼 필요가 있을 것이다.잡은 전혀 삭과가 형성되지 않았다. 이 결과는 종간 교잡종을 자방친으로 하고 그 자방친의 화분친을 사용할 때만 교잡이 이루어지고 있음을 나타내고 있다. 따라서 여교잡을 통한 종간잡종 품종육성 활용방안을 금후 적극 확대 검토해야 할 것이다하였다.함을 보이고 있다.X> , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서