• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.45-53
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• 2000

Two extraction methods for total petroleum hydrocarbon (TPH) from contaminated soil were evaluated. The soil used for this study was sandy loam. Diesel oil was selected as representative petroleum hydrocarbons and was spiked at 100, 10,000, 50,000mg TPH/kg dry soil. Percentage recovery of TPH by shaking method was higher compared to Soxhlet extraction. At extraction time of 2 hours and sample to solvent ratio of 1 : 5, the highest percentage recovery was obtained. In this condition, percentage recovery of TPH in soil contaminated with 100mg/kg and 50,000mg/kg as TPH was 95.9% and 95.5%, respectively The volume of solvent lost by volatilization in shaking method was relatively small compared to Soxhlet extraction.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.305-314
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• 2010

The stabilization process using limestone ($CaCO_3$) and steel making slag as the immobilization amendments was investigated for As contaminated farmland soils around Chonam abandoned mine, Korea. Batch and continuous column experiments were performed to quantify As-immobilization efficiency in soil and the analyses using XRD and SEM/EDS for secondary minerals precipitated in soil were also conducted to understand the mechanism of Asimmobilization by the amendments. For the batch experiment, with 3% of limestone and steel making slag, leaching concentration of As from the contaminated soil decreased by 62% and 52% respectively, compared to that without the amendment. When the mixed amendment (2% of limestone and 1% of steel making slag) was used, As concentration in the effluent solution decreased by 72%, showing that the mixed of limestone and steel making slag has a great capability to immobilize As in the soil. For the continuous column experiments without the amendment, As concentration from the effluent of the column ranged from 50 to $80\;{\mu}g/L$. However, with 2% limestone and 1% steel making slag, more than 80% diminution of As leaching concentration occurred within 1 year and maintained mostly below $10\;{\mu}g/L$. Results from XRD and SEM/EDS analysis for the secondary minerals created from the reaction of the amendments with $As^{+3}$ (arsenite) investigated that portlandite ($Ca(OH)_2$), calcium-arsenite (Ca-As-O) and calcite ($CaCO_3$) were main secondary minerals and the distinct As peaks in the EDS spectra of the secondary minerals can be observed. These findings suggest that the co-precipitation might be the major mechanisms to immobilize As in the soil medium with limestone and steel making slag.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.405.1-405
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• 2002

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.269-278
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• 2023

The pollution status of heavy metals in the soils of children's playground was investigated for a sustainable soil environment in urban parks of Seoul. As sampling sites, 281 locations were selected from a 7 districts in the Seoul city. The overall mean concentrations of the heavy metals (Cd 0.21 mg/kg, Cu 5.97 mg/kg, As 2.40 mg/kg, Pb 7.55 mg/kg, Zn 34.08 mg/kg, Ni 4.22 mg/kg, Hg 0.02 mg/kg and Cr6+ not detected.) in the soils of the palygrounds were lower than the worrisome level in criteria for area 1 in Korea soil environment conservation act. In addition, when the soil pollution grade (SPC) was evaluated as an average value, it was found to be less than 100, the first grade, at all points in the seven autonomous districts, indicating thatthe soil was in good soil condition. However, when evaluated as the maximum value, some of the five districts showed values of 100 or more. Therefore, it was found that continuous management and interest of the local government, which is the management body of children's playgrounds, is necessary for a safe soil environment.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.293-300
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• 2012

This study was to investigate the unsuitable rate of the storage facilities, the changes in corrosion process over time after installation according to the status, the time to install the facilities, years elapsed after facilities installation, inspection of methods and motivation, and so on, based on the results of the inspection at the petroleum storage facilities conducted by domestic soil-relate specialized agency to derive optimal management plans which meet the status of soil contamination facilities. The results showed that the facilities more than 5 years after the initial leak test at the time of the installation need to be inspected periodically by considering costs of leak test and remediation of polluted soil. The inspection period can be decided by cost and leak test methods showing discrepancies for the results obtained from individual test whether it was direct or indirect. To compensate these matters, we suggested that the direct inspection method on regular schedule is recommended. On the other hand, the inspection can be voluntarily completed to ease burden of the results by inspection or equivalent level to this inspection method. Also, it may need improved construction supervision and performance test system to minimize the occurrence of the nature defects in installing the facilities as well as the upgrade program for the facilities during intervals of inspection period.

• Journal of Soil and Groundwater Environment
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• v.10 no.6
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• pp.68-74
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• 2005

This study was carried out to evaluate the feasibility of field-scale sequential soil washing process for remediation on Kyongsangnamdo D mine soils which was heavily contaminated by arsonic. Arsenic concentration of untreated soils was $321\pm32mg/kg$. By applying the basic operating condition which was proposed from several pilot-scale experiments, arsenic concentration of treated soils was reduced 2.04 mg/kg ($99\%$ removal efficiency). We optimized the basic operating condition (mainly on washing solution concentration, cut-off size, and mixing ratio) to improve efficiently and economically the field-scale sequential soil washing process. The resulting optimized conditions were that solution concentration is 0.2M HCl, 1.0M HCl, 1.0M NaOH, that the cut-off size is 0.15mm (seive $\sharp$100), and that the mixing ratio is 1 3. Also, the optimized pH value for soil washing effluent treatment was 6 (33 ppb), in which the precipitation disruption caused by supersaturation of the floe did not occur. Results of TCLP tests showed that arsenic concentration from the washed gravels was 1.043 mg/L, that from soils ND (not detected), and that from filter cakes 0.066 mg/L. Also, the water content as a percentage of dewatered sludges was low $(48\%)$ and so the dewatered sludges can be disposed by landfilling. Through these results, we can concluded that tile field-scale sequential soil washing process developed in this study is adopted for remediation of arsenic-contaminated soils.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.469-469
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• 2011

점적관개는 과수원이나 시설재배에서 수량 및 품질을 향상시키기 위해 물을 효율적으로 사용하여, 비료 및 농약 등에 의한 비점원 오염을 감소시킬 수 있는 방법으로 자주 고려되어 왔다. 효율적인 점적관개를 위해서는 관개시 토양의 수분 분포에 대한 정보가 필요하며, 이는 점적기의 간격, 관개수량 기준에 중요한 기초자료로 활용된다. 시설재배지에서 토양수분의 관리 및 관개를 위한 점적기 설치 간격, 유량은 현재 관리자의 경험적인 지식에 의존하고 있으며, 재배지 토성의 변화에 적절히 대응 할 수 있는 설계 기준 구축이 전무한 상태이다. 본 연구에서는 점적관개 시 토양수분 분포의 변화 양상을 국내토양 및 시설재배 현황을 반영하여 실험설계를 실시하였으며 토양수분 재분배 및 균일성 평가 방법을 적용하여, 적정 점적관개 시스템의 설계 및 운영에 필요한 기초자료를 제공하였다.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.20-26
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• 1997

This paper examines the influences of mining activities on the concentrations of heavy metals in soils in the vicinity of the Dalsung Cu-W mine, Korea. Geochemical surveys were undertaken in the Dalsung mine area and sampling of surface and subsurface soils was carried out. Samples were prepared using 0.1 N HCI, HNO$_3$-HClO$_4$, and aqua regia, and analyzed for Cd, Cu, Pb and Zn by Atomic Absorption Spectrometry. In addition, soil samples were sequentially extracted to investigate the chemical speciation of heavy metals in soils. Heavy metals are highly contaminated in soils in the vicinity of mining area ranging up to 28 $\mu\textrm{g}$/g Cd, 5000 $\mu\textrm{g}$/g Cu, 2390 $\mu\textrm{g}$/g Pb and 930 $\mu\textrm{g}$/g Zn by the method using HNO$_3$-HClO$_4$. The pollution indices calculated with the permissible levels are up to 49 in surface and subsurface soils, which are considered sufficient to raise environmental problems. However, the heavy metal levels by the method using 0.1 N HCl are not higher than Korean standard for soil contamination. It suggests that analytical methods and soil standard should be re-examined. From the results of the sequential extraction methods for metal speciation, total Cu, Pb and Zn concentrations may be determined by analytical methods using HNO$_3$-HClO$_4$ or aqua regia, and exchangeable phase of those metals by the method using 0.1 N HCl.

• Economic and Environmental Geology
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• v.41 no.2
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• pp.201-210
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• 2008

The mixing treatment process using lime (CaO) and limestone ($CaCO_3$) as the immobilization amendments was applied for heavy metal contaminated filmland soils around Goro abandoned Zn-mine, Korea in the batch and pilot scale continuous column experiments. For the batch experiments, with the addition of 0.5 wt.% commercialized lime or limestone, leaching concentrations of As, Cd, Pb, and Zn from the contaminated filmland soil decreased by 70, 77, 94, and 95 %, respectively, compared to those without amendments. For the continuous pilot scale column experiments, the acryl column (30 cm in length and 20 cm in diameter) was designed and granulated lime and limestone were used. From the results of column experiments, with only 2 wt.% of granulated lime, As, Cd, and Zn leaching concentrations decreased by 63%, 97%, and 98%, respectively. With 2 wt.% of granulated limestone, As leaching concentration reduced from 135.6 to 30.2 ${\mu}g/L$ within 5 months and maintained mostly below 10 ${\mu}g/L$, representing that more than 46% diminution of leaching concentration compared to that without the amendment mixing. For Cd and Zn, their leaching concentrations with only 2 wt.% of limestone mixing decreased by 97%, respectively compared to that without amendment mixing, suggesting that the capability of limestone to immobilize heavy metals in the filmland soil was outstanding and similar to that of lime. From the column experiments, it was investigated that if the efficiency of limestone to immobilize heavy metals from the soil was similar to that of lime, the limestone could be more available to immobilize heavy metals from the soil than lime because of low pH increase and thus less harmful side effect.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.90-90
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• 2000