• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.590-598
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• 2006

In-situ Air sparging (IAS) is a groundwater remediation technique, in which organic contaminants volatilize into air form the saturated to vadose zone. This study was carried out to evaluate the effect of sludge and soil microbial community structure on air sparging of Total Petroleum Hydrocarbons (TPH) contaminated groundwater soils. In the laboratory, diesel (10,000 mg TPH/kg) contaminated saturated soil. The Air was injected in intermittent (Q=1500 mL/min, 10 minute injection and 10 minute idle) modes. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for experiment with sludge soil samples that were closely related to Agrococcus, Flavobacterium, Thermoanaerobacter, Flexibacter and Shewanella, etc, in the clone library. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil the fate of microorganisms in natural microbial community.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.3-10
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• 2003

Soil and groundwater contamination by petroleum hydrocarbon products is only one of many environmental problems in Korea. However, many environmental consulting companies have been targeted their business on this subject because the petroleum-oil-lubricant (POL) products have been widely used product and accidental releases of the products from storages resulted numerous small and large contaminated sites throughout Korea. Therefore, many small and large companies are actively participating in environmental assessment and remediation projects for the POL contaminated sites. Remedial technologies for the POL contaminated sites have been developed for many years by government and private institutions throughout the world. Development of a new decontamination technology for the POL contaminated sites is no longer attractive issue in research community because scientific bases of most cost-effective remedial technologies are well understood and have been used in the field by commercial sector. Numerous sites contaminated by underground tanks at gas stations have been remediated by relatively small companies in this country. We should appreciate their noticeable contributions as a frontier under very difficult market environment in Korea. We heard many successful stories as well as a few failure stories. Soil-groundwater remediation of POL contaminated site is not a simple task as shown in the text books or protocols. Therefore, failure risk is always with us, which requires continuous efforts for improvement of the technologies by the users and developers. In this presentation, author will discuss technical problems encountered and improvement made during implementation of several remedial technologies applied by Samsung Environmental Team. This is not a presentation about research or case study. We want to share our thought and experience with environmental engineers actively engaged in soil and groundwater remediation projects in Korea.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.286-293
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• 2006

Three hundred thirty two bacterial colonies which were able to degrade crude oil were isolated from soil samples that were contaminated with oil in Daejon area. Among them, one bacterial strain was selected for this study based on its low surface tension ability, and this selected bacterial strain was identified as Pseudomonas sp. G314 through physiological-biochemical tests and analysis of its 16S rRNA sequence. Pseudomonas sp. G314 showed a high resistance to antibiotics such as ampicillin, chloramphenicol, spectinomycin, and streptomycin, and heavy metals such as Li, Cr, and Mn. It was found that the optimal pH and temperature for biosurfactant production of Pseudomonas sp. G314 were pH 7.0 and $30^{\circ}C$, respectively. After seven hours of inoculated, the biosurfactant activity reached the maximum, and surface tension of the culture broth was decreased from 72 to 25 dyne/cm. The crude biosurfactant was obtained from the culture broth by acid precipitation, followed by solvent extraction, evaporation and then freeze drying. The CMC (critical micelle concentration) value of the crude biosurfactant was 20 mg/L.

• Journal of Korean Society on Water Environment
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• v.24 no.1
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• pp.19-29
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• 2008

Hot air sparging is a groundwater remediation technique, in which organic contaminants volatilized into hot air from the saturated to vadose zone. In the laboratory diesel (10,000 mg TPH/kg) was spiked in contaminated saturated aquifer soil. The hot air ($34.9{\pm}2.7^{\circ}C$) was injected in intermittent (Q=1,500 mL/min, 10 minute injection and 10 minute idle) modes. We performed microcosm tests using the groundwater samples to assess TPH reductive remediation activity. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for hot air sparging experiment with sludge soil samples that were closely related to Bacillus (149 bp, Firmicutes), Methlobacterium (149 bp, Euryarchaeotes), Pseudomonas (492 bp, ${\gamma}$-Proteobacteria), etc., in the clone library. In this study we find that TPH-water was reduced to 78.9% of the initial value in this experiment aquifer. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil fate of microorganisms in natural microbial community.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1372-1377
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• 2009

For the remediation of the subsurface contaminated by nonaqueous phase liquids(NAPLs), it is important to characterize the NAPL zone properly. Conventional characterization methods provide data at discrete points. To overcome the weak points of conventional characterization methods, the partitioning tracer method has been developed and studied. The average saturation of NAPL($S_n$), which is the representative and continuous saturation value within contaminated site, can be calculated by comparing the transport of the partitioning tracers to that of the conservative tracer in the partitioning tracer method. In this study, the application of the partitioning tracer method in heterogeneous media was investigated. To represent the heterogeneous condition of subsurface, a two-dimensional soil box was divided into four layers and each layer contained different sized soils. Soils in the soil box were contaminated by the mixture of kerosene and diesel, and partitioning tracer tests were conducted before and after the contamination using methanol as conservative tracer and 4-methyl-2-pentanol, 2-ethyl-1-butanol, and hexanol as partitioning tracers. The response curves of partitioning tracers from contaminated soils were separated and retarded in comparison with those from non-contaminated soils. The contamination of soils by NAPLs, therefore, can be detected by partitioning tracer method considering these retardations of tracers. From our experiment condition, the average saturation of NAPLs calculated by partitioning tracer method using the methanol as conservative tracer and hexanol as partitioning tracer showed the highest accuracy, though all results were underestimated. Further studies, therefore, were needed for improving the accuracy using the partitioning tracer test in heterogeneous media.

• Journal of Life Science
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• v.21 no.1
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• pp.134-140
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• 2011

One hundred forty five bacterial colonies which were able to degrade crude oil were isolated from soil samples that were contaminated with oil in the Daejon area. Among these colonies, one bacterial strain was selected for this study based on its low surface tension ability, and this selected bacterial strain was identified as Pseudomonas sp. Z1 through physiological-biochemical tests and analysis of its 16S rRNA sequence. Pseudomonas sp. Z1 showed a high resistance to antibiotics such as chloramphenicol and ampicillin, as well as heavy metals such as lithium, manganese, and barium. It was found that the optimal pH and temperature for biosurfactant production of Pseudomonas sp Z1 were pH 6.0-7.0 and $30^{\circ}C$, respectively. After ten hours of inoculation, the biosurfactant activity of the culture broth decreased rapidly, and had maximum surface tension (28 dyne/cm) after twenty-one hours incubation. The biosurfactant activity of the culture broth was also decreased up to 2% NaCl concentration.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.9
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• pp.2189-2196
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• 2015

According to increase environmental pollutions and fuel costs, The study of energy saving in the ship is proceeding actively. PCS is pump control system for cooling system in the ship to improve the energy efficiency by controling rotation speed of sea water pump, fresh water pump and position of 3way valve. In this paper, we develop the PCS simulator that has an environment similar to the cooling system of the actual vessel to ensure reliability of the PCS. Also, PC-based control and data storage system for PCS simulator is developed. To develop this system, National Instrument's cDAQ and LabVIEW are used. Finally, confirm the behavior of the simulator by analyzing the saving data.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.02a
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• pp.14-28
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• 2001

As basic study for purpose bioremedation in oil-contaminated environment, Primarily, we isolated biosurfactant producer- strains utilized of oil-agar plate, and measured surface tension and emulsifying activity. We investigated in oil-contaminated soil and sea water. In this laboratory, Pseudomonas sp. EL-012S strain isolated from oil-contaminated soil was able to product novel biosurfactant under the optimal culture condition. Its condition was n-hexadecane 2.0%, NH$_4$NO$_3$0.4%, Na$_2$HPO$_4$0.6%, KH$_2$PO$_4$0.4%, MgSO$_4$.7$H_2O$ 0.02%, CaCl$_2$.2$H_2O$ 0.001%, FeSO.7$H_2O$ 0.001%, initial pH 7.0 and aeration at 3$0^{\circ}C$, respectively. This biosurfactant was produced in both late-exponential and early-stationary phase. The biosurfactant from Pseudomonas sp. EL-012S was composed of carbohydrate, lipid and protein. The purified-biosurfactant was examined two (biosurfactant type I, II) with the silica gel G60 column chromatography and the purified biosurfactant confirmed thin layer chromatography, high performed liquid chromatography and gas chromatography. The biosurfactant type I involved in carbohydrate-lipid-protein characteristics lowered surface tension of water to 27dyne/cm and interfacial tension 4.5dyne/cm aginst to n-hexadecane and the biosurfactant type B involved in carbohydrate lipid characteristics lowered surface tension of water to 30dyne/cm and interfacial tension 8dyne/cm against to n-hexadecane. Specially type I had the properties such as strong emulsifying activity, emulsion stability, pH-stability, thermo-stability, high cleaning activity and forming ability.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.27-34
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• 2003

In this study, potential degradation of MTBE and other gasoline oxygenates by pure culture ENV425 and mixed culture isolated from gasoline contaminated soil using butane as the sources of carbon and energy was examined and compared. Butane monooxygenases(BMO) of butane-grown ENV425 and mixed culture generated 1-butanol as a major metabolite of butane oxidation and addition of acetylene, specific inhibitor of monooxygenase, inhibited both butane oxidation and 1-butanol production. The results described in this study suggest that alkanes including propane, pentane, and butane are effectively utilized as a growth substrate to oxidize MTBE cometabolically. And also BTEX compounds could be the potential substrate of the MTBE cometabolism. Cell density also affected on the MTBE degradation and transformation capacity(Tc). Increasing cell density caused increasing MTBE degradation but decreased transformation capacity. Other result demonstrated that MTBE and other gasoline oxygenates, ETBE and TAME, were degraded by butane-grown microorganism.

• Journal of Soil and Groundwater Environment
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• v.17 no.5
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• pp.20-30
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• 2012

In case of analyzing PAHs (EPA 16 compounds) in oil-contaminated soils, the lump of peaks may occur because of the aliphatic and polar compounds in oil. This phenomenon is due to the lower accuracy of the analysis. To solve this problem, evaluation of application of silicagel-alumina multi-layer fraction was performed using standard substances and oil-contaminated soils. As a result of application of silicagel-alumina multi-layer fraction cleanup method using standard substances, recovery rates of surrogate standards (5 compounds including Naphthalene-d8) were 83~100% and those of target standards were 75~129%. These were to meet the target values (60~130%) in this study. When used 4% water-silicagel column analyze PAHs in oil-contaminated soils, Some problems were generated for quantitative analysis of PAHs; concentration of PAHs was underestimated due to an upward baseline of internal standard (recovery rate: less than 60%) and overestimated by the lump of peaks which were not purified (the biggest recovery rate: more than 400%). On the other hand, in case of silicagel-alumina multi-layer fraction cleanup method, recovery rate of surrogate standards were 61~101.6%. Therefore this cleanup method was considered a valid method to improve accuracy of analysis of PAHs in oil-contaminated soils.