• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.479-482
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• 2003

In this study, the solubilization of dense nonaqueous phase liquid (DNAPL) using oil-based emulsion was investigated for aquifer remediation. The micro-sized oil emulsion has large surface areas and buoyancy force, therefore it can be effective in treating DNAPL pool of the aquifer without downward migration of DNAPLs. The emulsion was prepared using silicone oil and mechanical homogenization. And the prepared emulsion had micro-sized similar distribution: 99 % in number and 80 % in volume were less than 10${\mu}{\textrm}{m}$. As target pollutants, trichloroethylene and 1, 2 dichlorobenzene were selected. All of used DNAPLs were solubilized successfully in oil-based emulsion. Even at low oil percentage, emulsion showed good solubility against pollutants. Therefore, the remediation using oil-based emulsion was considered as an effective alternative in dealing with DNAPLs of the aquifer.

• 방사선산업학회지
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• 제4권1호
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• pp.79-83
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• 2010

The pollutants in subsurface soil are advected by groundwater flow and transported by the hydrodynamic dispersion. In this study, laboratory-scale experiments by using a radioisotope were conducted to evaluate the characteristics of the transport and dispersion of pollutants in the soil. The hydraulic model of the laboratory-scale was manufactured based upon its geometric similarity. Tc-99m having a short half-life was used with a tracer and it was injected instantaneously into the soil. Tc-99m milked from a $^{99}Mo/^{99m}Tc$ portable generator fabricated for medical purposes had 0.141 MeV of gamma radiation. The experiments are performed by the different conditions like the variations of groundwater velocity and the results are analyzed by the measured CPS of Tc-99m.

• 한국물환경학회지
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• 제27권1호
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• pp.120-128
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• 2011

Korea Groundwater Quality Monitoring Network is a database of annual groundwater quality survey results to prevent groundwater pollution. We estimated contamination index (CI) values for each type of land use, and analyzed temporal trends of pollutant concentration data in the Groundwater Quality Monitoring Network from 2001 to 2009. Among the pollutants considered in the database, the concentrations of nitrate and chloride were higher than their standards. In the case of nitrate, recreation parks, golf courses and general waste dumping regions showed increasing trends according to linear regression analysis, whereas industrial complexes and residential regions of urgan and recreation parks showed increasing trends in the chloride concentration data. According to multiple variable linear regression analysis, EC, pH and topography were major factors influencing CI values. These results suggest that groundwater with a high CI value and increasing trend is vulnerable for potential contamination, which requires more careful groundwater pollution control.

• 한국지반환경공학회 논문집
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• 제11권8호
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• pp.25-32
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• 2010

석유계 탄화수소 화합물로 인한 토양과 지하수 오염은 환경과 건강에 영향을 미치는 주된 원인으로 제기되어 왔다. 이러한 오염물질들은 흡착포, 활성탄 또는 중력 방식의 유수분리 장치 등을 이용하여 처리하고 있다. 하지만 이러한 경우 자유상 유류(free product)로 존재하는 경우에는 효과적이나 에멀젼 상태의 유류는 제거할 수 없는 것으로 알려져 있다. 따라서 본 연구에서는 굴착시 예상되는 지하수의 고농도 현탁성 고형물로 인한 지하수 처리시 문제점과 TPH(Total Petroleum Hydrocarbon)를 어떻게 효율적으로 제거할 수 있는지 방안을 제시하고자 한다. 고분자 폴리머를 사용하여 혼화 응집 실험을 수행한 결과 5분 이내에 SS(Suspended Solids)와 COD(Chemical Oxygen Demand) 농도가 지하수 수질 기준을 만족하는 것을 나타났으나, TPH 농도는 방류수 수질 기준을 만족하지 못하는 것으로 나타났다. DAF(Dissolved Air Flotation) 실험 결과 단일 DAF 공정으로는 방류수 수질 기준을 만족하지는 못하였다. 단일 DAF 반응조를 이용하여 DAF와 혼화 응집 반응을 동시에 수행하는 경우 20분에 모든 기준을 만족하는 것으로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권5호
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• pp.8-15
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• 2016

Bioremediation, which uses microbes to degrade most organic pollutants in soil and groundwater, can be used in solving environmental issues in various polluted sites. In this research, a wind-driven bioventing system is built to degrade about 20,000 mg/kg of high concentration diesel pollutants in soil-pollution mode. The wind-driven bioventing test was proceeded by the bioaugmentation method, and the indigenous microbes used were Bacillus cereus, Achromobacter xylosoxidans, and Pseudomonas putida. The phenomenon of two-stage diesel degradation of different rates was noted in the test. In order to interpret the results of the mode test, three microbes were used to degrade diesel pollutants of same high concentration in separated aerated batch-mixing vessels. The data derived thereof was input into the Haldane equation and calculated by non-linear regression analysis and trial-and-error methods to establish the kinetic parameters of these three microbes in bioventing diesel degradation. The results show that in the derivation of μ_m (maximum specific growth rate) in biodegradation kinetics parameters, K_s (half-saturation constant) for diesel substance affinity, and K_i (inhibition coefficient) for the adaptability of high concentration diesel degradation. The K_s is the lowest in the trend of the first stage degradation of Bacillus cereus in a high diesel concentration, whereas K_i is the highest, denoting that Bacillus cereus has the best adaptability in a high diesel concentration and is the most efficient in diesel substance affinity. All three microbes have a degradation rate of over 50% with regards to Pristane and Phytane, which are branched alkanes and the most important biological markers.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권6호
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• pp.62-71
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• 2008

환경에는 매우 다양한 유해화학물질이 존재하며 지속적으로 새로운 화학물질이 개발되고 다시 환경 중으로 유출되고 있다. 화학물질의 관리나 규제를 위해서는 우선관리대상 오염물질(Priority Contaminants)을 결정해야 하는데, 이를 위한 과학적이고 정량적인 방법론으로는 우선순위선정(Chemical Ranking and Scoring; CRS)기법이 대표적이다. CRS기법에는 개발목적에 따라 다양한 평가인자들이 적용되는데 본 연구에서는 토양매체에서의 우선순위물질 선정시 필요한 인자를 제시하기 위해 다양한 CRS기법을 비교분석하여 토양특성을 고려할 수 있는 평가인자를 제시하였다. 연구대상 CRS는 국외에서 개발된 CHEMS-1, EURAM, SCRAM, ARET와 국내에서 개발된 CRS-Korea 및 그 외 기타 관련연구들이다. 기존에 개발된 CRS에 적용된 평가인자들을 비교분석한 결과 노출과 독성을 고려하여 우선순위물질을 선정하는데, 주로 화학물질의 잔류성, 생물축적성, 배출량 등을 공통적인 노출인자로 적용하고 있었고 독성인자로는 인체와 환경독성을 고려하고 있다. 본 연구에서는 토양매체의 우선순위물질선정을 위하여 이러한 CRS기법들이 공통적으로 적용하고 있는 인자들 이외에 토양매체의 특성을 고려할 수 있는 토양배출량, 토양오염 사고사건사례, 선진국의 규제국가수 등을 평가인자로 제안하였으며, 지하수매체와의 연계성을 위하여 지하수이동성 인자를 새로이 추가하였다. 본 연구결과는 CRS기법을 비교분석하여 토양에서의 유해화학물질 우선순위 선정시 고려되어야할 평가인자를 제안한 연구로 토양에 대한 CRS기법개발을 위한 기반연구로 활용될 수 있을 것이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.162-165
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• 1998

This research has been made in order to evaluate and characterize wastewater from closed coalmines throughout the country. The characteristics of the wastewater from closed coalmines are affected greatly with geochemical nature and are not changed significantly with the lapse of time. Pollutants concentration profile could be divided into two groups below and above pH of around 5.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.413-416
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• 2003

Micellar enhanced ultrafiltration(MEUF) is a surfactant-based separtaion technique which can remove dissolved organics or multivalent ions from water. In this study, trichloroethylene(TCE) and chromate were simultaneouly removed using MEUF and cetyltrimethylammoniun chloride (CPC) was used as a surfactant. The removal efficiency of chromate was 99% and that of TCE was more than 80%. The presence of TCE or chromate did not affect removal efficiency of each pollutants because the predominat mechanism of TCE and chromate are different.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.333-335
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• 2003

Deep Ocean Water is formed within restricted area including polar sea (high latitude) by cooling of surface seawater and globally circulated in the state of insolation with surface seawater. Although not as obvious as estuaries mixing, Brine groundwater is mixture of recirculated seawater and groundwater. Seawater having high osmotic pressure infiltrate into unconfined aquifer where is connected to the sea. The ions dissolved in seawater are present in constant proportions to each other and to the total salt content of seawater. However deviation in ion proportions have been observed in some brine groundwater. Some causes of these exception to the Rule of constant proportions are due to many chemical reactions between periphery soil and groundwater. While Deep Ocean Water (DOW) have a large quantity of functional trace metals and biological affinity relative to brine groundwater, DOW have relatively small amount of harmful bacteria and artificial pollutants.

• 한국환경과학회지
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• 제11권7호
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• pp.721-727
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• 2002

The characteristics of drinking groundwater quality at Chung Cheong Nam Do was analyzed by investigating the 3,086 groundwater data which were carried out the water quality inspection from Jan. 1998 to Dec. 1998. It was found that all the mean concentration of items was not over the drinking water quality standard except Zn at Yeongee area. The highest mean concentration of nitrate was $8.2 mg/{\ell}$ at Hongsung area. And the mean concentrations of nitrate and ammonium at Sucheon, Yesan, Yeongee were relatively higher. It was considered that the groundwater of that area was contaminated by breeding livestock as farm pollutants. The mean concentrations of chloride, hardness and evaporation residual at coastal regions were higher than inland regions. Especially the mean concentration of chloride was 2.5 times higher. It was considered that the groundwater at coastal regions was affected by seawater. It was found that the correlation between Fe and Mn was relatively high(r=0.776) and the correlation between hardness and evaporation residual was very high(r=0.983). The rainfall series and detection rate of E-coli had the hydrologic persistence. The correlation between the detection rate and rainfall series over 150 mm was very high (r=0.9146). Therefore it is surely required to control the groundwater sanitation in the rainy season.