• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.42-52
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• 2011

In this laboratory study, the changes in gas-exposed perchloroethene (PCE) saturation in sand during a PCE removal process were measured using gaseous tracers. The flux of fresh air through a glass column packed with PCEcontaminated, partially water-saturated sand drove the removal of PCE from the column. During the removal of PCE, methane, n-pentane, difluoromethane and chloroform were used as the non-reactive, PCE-partitioning, water-partitioning, and PCE and water-partitioning tracers, respectively. N-pentane was used to detect the PCE fraction exposed to the mobile gas. At water saturation of 0.11, only 65% of the PCE was found to be exposed to the mobile gas prior to the removal of PCE, as calculated from the n-pentane retardation factor. More PCE than that detected by n-pentane was depleted from the column due to volatilization through the aqueous phase. However, the ratio of gas-exposed to total PCE decreased on the removal of PCE, implying gas-exposed PCE was preferentially removed by vaporization. These results suggest that the water-insoluble, PCE-partitioning tracer (n-pentane in this study), along with other tracers, can be used to investigate the changes in fluid (including nonaqueous phase liquid) saturation and the removal mechanism during the remediation process.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.3
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• pp.231-241
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• 1997

A tracer model was applied in the Far East Asia to investigate the dry deposition rates of air pollutants on Korean Peninsula originated from different countries including China and Japan. Wind direction was chosen to predict the maximum deposition rates and SO$_2$ was chosen as a tracer to estimate the source strength. Model simulation shows that inflow, deposition and airborne ratios of China-originated SO$_2$ were 50%, 8% and 30%, respectively, at most. Also it was found that deposition, outbounded and airborne ratios of Korea-originated SO$_2$ were 15~77%, 8~75%, and 3~30%, respectively Model simulation also shows that inflow, deposition and airborne ratios of Kyushu-originated SO$_2$ were, 30~45%, 8~14％ and 20~25%, respectively. This study shows that tracer model can be applied on the estimation of air pollutants partitioning in regional scale and that more sophisticated modules and schemes can be developed and applied to better predict the transboundary amounts of air pollutants in this region.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.299-300
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• 2008

• Analytical Science and Technology
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• v.25 no.1
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• pp.14-18
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• 2012

Rn-222 was used as a natural radioactive isotope tracer to evaluate non-aqueous phase liquid(NAPL) contaminated soil and aquifer. In the case of soil sample, Rn-222 concentration was inversely decreased with diesel concentration in the granite soil sample and it was decreased about 30% at the 13% diesel contaminated soil. For evaluating trichloroethylene (TCE) contaminated aquifer, the natural radioisotope Rn-222 was used as naturally occurring partitioning tracer for the approximate localization and semiquantitative assessment of the TCE source zone. Rn-222 was analyzed for the estimation of TCE contamination ranges of the acquifer in the contaminated site at Wonju in Korea.

• Journal of Korean Society of Water and Wastewater
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• v.13 no.4
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• pp.62-71
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• 1999

The containment retardation capacities of four different aquifers were evaluated in a preliminary study for development of bank filtration in the Young San river area. $NO_3-N$, $NO_2-N$, $NH_4^+-N$, Fe, Mn, phenol, and chloride were selected as the target contaminants and a nonreactive tracer, respectively. Batch isotherm tests were conducted to measure the partition coefficients of the target contaminants. The mass transport parameters of nonreactive tracer were estimated from column tests. From the results of bath isotherm tests, it was shown that lower stream aquifer materials have greater partition coefficients of $NO_3-N$, $NH_4^+-N$, Mn, and phenol than the upper stream aquifer materials; however, there was no significant position-dependent trend for Fe. All aquifer materials tested have the same range of partition coefficients for $NO_2-N$. Column tests showed that the molecular diffusion of Cl- was much less than the mechanical dispersion; and there was no significant difference between the estimated dispersivities of tested aquifer materials. Consequently, it seems that the difference in the containment retardation capacities between four aquifers tested in this study would primarily result not from hydrodynamic dispersion but from partitioning.

• Journal of Soil and Groundwater Environment
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• v.27 no.spc
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• pp.99-112
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• 2022

From early 2000, many researchers in the groundwater and soil environment remediation project tried to calculate the pollution level and pollution remediation cost and reflect it in the design. In addition, by identifying the movement characteristics of oil pollutants in the underground environment, many researchers tried to derive design factors necessary for pollution purification. However, although the test should be conducted in an area contaminated with oil, the toxicity and risk are too great for testing by deliberately leaking pollutants that are harmful to the human body. And as oil-contaminated areas are promoted by military units such as returned US military bases, there is a limit to access by the general public. In addition, since the indoor simulation test and the field application test have been carried out separately from each other, it was difficult to compare and review various simulation tests Therefore, in this study, PITT (Partitioning Interwell Tracer Test) and analysis methods were specifically presented through actual tests so that field workers could easily use them with the help of the military base and the Korea Rural Community Corporation Soil Environment Restoration Team. However, in order to directly reflect the distribution tracer test results in the pollution remediation design, it is necessary to reduce the analysis errors by comparing the analysis results of the existing soil pollution survey, physical exploration, and numerical modeling. In addition, it is judged to be cautious in the analysis because errors can easily occur due to various factors such as the type of oil at the polluted site, the hydraulic conductivity of the aquifer, and the skill of the researcher.

• Journal of Radiation Protection and Research
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• v.25 no.2
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• pp.99-107
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• 2000

Through the results of off-gas analysis at 3 sampling points in Plasma Arc Melting vitrification pilot plant, it was evaluated the partitioning of spiked materials in off-gas and the decontamination characteristic of off-gas treatment system. Spiked materials are hazard_us heavy metals(Pb, Cd, Hg), radioactive surrogate(Co, Cs) and radioactive materials($^{60}Co,\;^{137}Cs$). Through the Trial burn tests, Decontamination factor of spiked materials in off-gas treatment system is calculated.