• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.351-354
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• 2002

In this study, variation of electrochemical parameters and characteristics of lead immobilization due to phosphoric acid injection in soil were studied during electrokinetic remediation of lead contaminated soil. TCLP result showed about 100% of soil was satisfied TCLP regulation criteria. And injected ion from cathode reservoir by ionmigration was proportionate to concentration of phosphoric acid and elapsed time. Therefore, when removal is infeasible or not cost-effective, in situ immobilization method would be more effective.

• Environmental Engineering Research
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• 제18권4호
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• pp.221-227
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• 2013

A risk assessment of environmental media was performed for the inhabitants in the area of the abandoned Nokdong metal mine. Soil, groundwater, and crop samples were collected from September to October 2008 around the mine. After pretreatment of these samples, metal concentrations were measured, and a risk assessment was performed using the Korean soil-contamination risk assessment guidelines. Lead (Pb) and arsenic (As) intake rates were the highest for inhalation of soil dust. The cancer risks from ingestion of As-contaminated groundwater, inhalation of As-, Cd-, and Pb-contaminated soils, and contact of As-contaminated soils exceeded the acceptable risk. The sum of all carcinogenic risks was $9.29{\times}10^{-3}$. The non-carcinogenic risk was highest for ingestion of As-contaminated water (11.0), followed, in descending order, by inhalation of Hg-contaminated soil and ingestion of Pb-contaminated water. Most of the risks were associated with As, Cd, Pb, and Hg contamination, and therefore, these metals were considered to be potential toxic carcinogens and non-carcinogens for humans in this area. In this study, the non-carcinogenic risks of ingestion of contaminated water or crops, as well as those associated with the inhalation of soil dust were observed.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권4호
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• pp.113-121
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• 2015

The contaminated soil at abandoned smelter areas present challenge for remediation, as the degraded materials are typically deficient in nutrients, and rich in toxic heavy metals and metalloids. Bioremediation technique is to isolate new strains of microorganisms and develop successful protocols for reducing metal toxicity with heavy metal tolerant species. The present study collected metal contaminated soil and characterized for pH and EC values, and heavy metal contents. The pH value was 5.80, representing slightly acidic soil, and EC value was 13.47 mS/m. ICP-AES analytical results showed that the collected soil samples were highly contaminated with various heavy metals and metalloids such as lead (183.0 mg/kg), copper (98.6 mg/kg), zinc (91.6 mg/kg), and arsenic (48.1 mg/kg), respectively. In this study, a bacterial strain, Bacillus cereus KM-15, capable of adsorbing the heavy metals was isolated from the contaminated soils by selective enrichment and characterized to apply for the bioremediation. The effects of heavy metal on the growth of the Bacillus cereus KM-15 was determined in liquid cultures. The results showed that 100 mg/L arsenic, lead, and zinc did not affect the growth of KM-15, while the bacterial growth was strongly inhibited by copper at the same concentration. Further, the ability of the bacteria to adsorb heavy metals was evaluated.

• 한국환경과학회지
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• 제19권2호
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• pp.255-260
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• 2010

A stabilization/solidification (S/S) process for lead (Pb) contaminated soils was evaluated using waste cow bone containing apatite like compounds. Soil samples obtained form firing range were treated with waste cow bone. The effectiveness of stabilization was evaluated based on the Korean Standard Leaching Test (KSLT) and soil pH. The leached concentration reduced with increased in dose of waste cow bone. Overall, the KSLT results showed that Pb concentration in soils are significantly affected by amount of waste cow bone. When soil amended with 20 % of waste cow bone, less than 0.1 mg/kg was leached, and soil pH was increased from 6.5 to 8.4. Same results were obtained when finer waste cow bone was applied. The reachable concentration of Pb in soil showed in inversely proportional to solid/liquid ratio. Aging periods indicate improving mix design was applied. Relatively high lead concentrations was observed at the first 1 days, however leaching profile are reduced significantly over time for all mix designs.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권1호
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• pp.60-66
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• 2008

본 연구에서는 실제 납 탄알로 오염된 사격장 토양에 대해 토양세척기법을 적용하기위한 lab-scale 실험을 수행하였으며 다음과 같은 결론을 얻을 수 있었다. 토양오염공정시험법과 EPA Method 3050B 분석결과 각각 4,803.5 mg/kg, 9,443 mg/kg으로 나타났다. 회분식 토양세척 실험에서 HCl을 세척제로 사용한 경우 농도증가에 따른 제거율은 로그적인(logarithmic) 경향을 나타내었고 0.1M에서 약 90% 정도 제거되었으며, EDTA는 농도에 비례하여 제거율도 증가하여 0.1 M에서 약 98%의 제거율을 보였다. 교반강도에 따른 시간별 세척효율을 분석한 결과, HCl과 EDTA를 사용한 경우 모두 교반강도의 증가와 비례하여 토양내 제거율이 증가하였으나 200 rpm과 300 rpm에서의 제거율은 유사한 것으로 나타났으며, 반응 초기 10분 이내에 대부분의 용출이 이뤄지고 60분 경과 후에는 제거율 증가가 둔화되었다.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.453-457
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• 2006

본 연구는 인산염을 이용하여 오염토양 내 존재하는 납을 불용성 금속인산염으로 고정화시킨 후 자연 상태에서 장기간의 용출특성을 평가하고자 칼럼실험을 수행하였다. 장기용출 실험결과 용출용액 중 납은 거의 검출되지 않았으며 잔류인의 농도도 0.1 mg/L 이하로 나타났다. 이는 납 오염토양에 액상인산염을 주입하여 형성된 hydroxypyromorphite가 장기적으로 안정한 화합물이기 때문으로 사료된다. 장기용출실험 후 칼럼 내 납의 이동특성은 미반응 토양에서는 수직방향으로 이동하는 것으로 나타난 반면에 반응토양에서는 안정한 상태를 유지하고 있었다.

• 한국토양환경학회지
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• 제4권3호
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• pp.77-84
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• 1999

본 논문에서는 고농도의 중금속 (납, 구리)으로 오염된 세 가지의 토양을 대상으로 sequential extraction 방법을 사용하여 토양과 중금속의 차이에 따른 결합 특성을 밝혀내고자 하였다. 고농도의 납과 구리로 오염된 토양을 형태별로 추출하였을 때 토양의 특성과 중금속의 종류에 따라 다른 결과를 보였다. 납은 문화동 토양에서는 Carbonate 형태가 37.7%로 가장 높았고 농토는 Amorphous Fe oxide 형태가 23.9%, 공단 토양에서는 Exchangeable 형태가 22.9%로 나타났다. 이에 비하여 구리는 세 가지 토양에서 공통적으로 Organically bound 형태가 농토에서 26.1%, 문화동 토양은 20.4%. 공단 토양에서는 24.1%로 높게 나타났고 Carbonate 형태와 Amorphous Fe oxide형태의 비율도 높게 나타났다. 또한 Crystallized Fe oxide 형태와 Residuals 형태도 납보다 높은 비율을 나타냄으로서 구리가 납보다는 토양과 강한 결합을 형성하는 것으로 생각된다. 이러한 토양과 중금속의 결합 특성은 오염 토양의 복원시 유용한 자료가 될 수 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.1-11
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• 2013

The actively soil pollution by the toxic heavy-metals like the arsenic, cadmium, lead due to the industrialization and economic activity. The uses the electrokinetic remediation of contaminated soil has many researches against the fine soil having a small size in the on going. However, it is the actual condition which the research result that is not effective due to the low surface charge of the particle and high permeability shows in the electrokinetic remediation in comparison with the fine soil in the case of the sandy soil in which the particle size is large. In this research, the electrokinetic remediation and ultrasonic wave fetch strategy is compound applied against the sandy soil polluted by the arsenic, cadmium, and lead removal efficiency of the sandy soil through the comparison with the existing electrokinetic remediation tries to be evaluated. First of all, desorption of contaminants in soil by ultrasonic extraction in the Pre-Test conducted to see desorption effective 5~15%. After that, By conducted Batch-Test results frequency output century 200 Khz, reaction time 30 min, contaminated soil used in experiment was 500 g. Removal efficiency of arsenic, cadmium, lead are 25.55%, 8.01%, 34.90%. But, As, Cd, Pb remediation efficiency less than 1% in EK1(control group).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.202-205
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• 2001

In this study, the electrokinetic remediation test for the kaolin contaminated by lead was performed and voltage, zeta potential, pH distribution, current, contamination transport in soil sample were studied and finite differential numerical analysis program(HERP) for a contaminated soil were compared with those of test. From the result of HERP, in the anode it was represented that the rest concentration was decreased with the voltage. Hence, if treatment time was continued for a long in the constant voltage, comparing with sample having no change in the rest concentration, it is considered that the voltage gradient is the control factor of the rest concentration.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.1-7
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• 2015

The most critical health effect of lead exposure is the neurodevelopmental effect to children caused by the increased blood lead level. Therefore, the endpoint of the risk assessment for lead-contaminated sites should be set at the blood lead level of children. In foreign countries, the risk assessment for lead-contaminated sites is conducted by estimating the increased blood lead level of children via oral intake and/or inhalation (United States Environmental Protection Agency, USEPA), or by comparing the estimated oral dose to the threshold oral dose of lead, which is derived from the permissible blood lead level of children (Dutch National Institute for Public Health and the Environment, RIVM). For the risk assessment, USEPA employs Integrated-Exposure-Uptake-Biokinetic (IEUBK) Model to check whether the estimated portion of children whose blood lead level exceeds 10 µg/dL, threshold blood lead level determined by USEPA, is higher than 5%, while Dutch RIVM compares the estimated oral dose of lead to the threshold oral dose (2.8 µg/kg-day), which is derived from the permissible blood lead level of children. In Korea, like The Netherlands, risk assessment for lead-contaminated sites is conducted by comparing the estimated oral dose to the threshold oral dose; however, because the threshold oral dose listed in Korean risk assessment guidance is an unidentified value, it is recommended to revise the existing threshold oral dose described in Korean risk assessment guidance. And, if significant lead exposure via inhalation is suspected, it is useful to employ IEUBK Model to derive the risk posed via multimedia exposure (i.e., both oral ingestion and inhalation).