• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.181-188
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• 2004

The contaminative influence of beef due to the inhalation of air and the ingestion of soil of livestock, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was comprehensively investigated with the improvement of the Korean food chain model DYNACON. As the results, it was found that both pathways can not be neglected at all in the contamination of beef in the case of an accidental release during the non-grazing period of livestock. The ingestion of soil was more influential in the contamination of beef than the inhalation of air over most time following an release. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was far greater compared with the cases of no precipitation. This fact was more distinct for a long-lived radionuclide $^{l37}Cs$ than a short-lived radionuclide $^{131}I$ (elemental iodine). Compared with the results for milk performed prior to this study, the contaminative pathways due to the inhalation of air and the ingestion of soil were more important in beef because of longer biological half-lives. On the other hand, in the case of an accidental release during the grazing period of livestock, radioactive contamination due to the ingestion of pasture was dominant irrespective of the existence of precipitation during an accidental release. It means that contaminative influence due to the inhalation of air and the ingestion of soil is negligible, like the cases of milk.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.97-102
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• 2007

An environmental survey from three abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to heavy metals influenced by past mining activities. Tailings contained high concentrations of heavy metals may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters for As, Cd, Cu and Pb have been used. The HQ values for heavy metals via the rice consumption were significantly higher compared with other exposure pathways in all metal mine areas. The resulting HI values in three mine areas were higher than 9.0, and their toxic risk due to rice ingestion was strong in these mine areas. The cancer risk of being exposed to As by the rice consumption from the A, B and C mine areas was $5.1\;{\times}\;10^{-3}$, $6.8\;{\times}\;10^{-3}$ and $3.1\;{\times}\;10^{-3}$, respectively. The As cancer risk via the exposure pathway of rice ingestion from these mine areas exceeds the acceptable risk of 1 in 10,000 set for regulatory purposes. Thus, the daily intakes of rice by the local residents from these mine areas can pose a potential health threat if exposed by long-term As exposure.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.77-78
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• 2002

원자력시설이나 원자력발전소에서 사고가 발생하여 대기로 방출된 방사능물질은 두 가지 주요경로를 통해 인체노출이 일어난다 첫째는 지역내 대기중에 존재하는 방사성물질이 인체의 호흡이나 피부 등을 통해 체내로 흡입되는 직접적인 노출 (Direct Exposures)이고 다른 하나는 방사능물질이 대기로부터 주변의 토양에 침적하고 이러한 토양에서 재배된 오염된 농작물들 (쌀, 보리, 밀, 또는 과일, 채소)을 인간이 섭취하거나, 방사능물질에 오염된 목초로 키운 축산물(소, 돼지, 닭 등)과 이들로 생산하는 제품들(우유, 고기, 달걀 등)을 인간이 섭취함으로써 이루어지는 보다 간접적인 인체노출(Indirect Exposures)이 있을 수 있다. (중략)

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1757-1763
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• 2000

To consider the nutrient removal characteristics of BNR process activating soil microorganisms under the influence of DPB and to clear the characteristics of DPB under anoxic condition was investigated in the this study. The batch tests were conducted using sludge sampled from the BNR process activating soil microorganisms during operation periods. The results of this study were summarized as follows: - The DPB(Denitrifying Phosphorus removing Bacteria) performing denitrification and phosphorus uptake in the anoxic phase plays an important role in removing nitrogen and phosphorus in the BNR process activating soil microorganisms. - The PUR(Phosphorus Uptake Rate) of DPB in the anoxic phase was to be about 50% of PUR in the aerobic phase. - The DPB in the BNR process turned out to be increasing nutrient removal efficiency of BNR process.

• Journal of Radiation Protection and Research
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• v.17 no.2
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• pp.15-23
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• 1992

Transport behaviors of Cs-137 and Sr-90 were analyzed and ingestion doses were calculated using dynamic model for rice field-rice-man pathway. Cs-137 binding strongly to soil remain longer in rice field than Sr-90. Foliar deposition on rice plant during growing period is the main contamination mechanism.

• Journal of Radiation Protection and Research
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• v.28 no.4
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• pp.299-309
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• 2003

In an accidental release of radioactive materials to the environment the contaminative influence of animal products due to the inhalation of air and the ingestion of soil of livestock, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was investigated with the improvement of the Korean dynamic food chain model DYNACON Although mathematical models for both contaminative pathways have been established for considering all animal products and incorporated into the model, investigation was limited to milk. As a result, it was found that both pathways are influential in the contamination of milk in the case of an accidental release during the non-grazing period of dairy cows. In the case of an accidental release during the non-grazing period, the inhalation of air was more influential than the ingestion of soil in the early days following an accidental release. While, it was the opposite with the lapse of time. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was greater compared with the cases of no precipitation, in general, because of a stealer deposition of radionuclides onto the ground. Precipitation during an accidental release was a less influential factor in $^{131}I$ (elemental iodine) contamination compared with the $^{137}Cs\;and\;^{90}Sr$ contaminations. In the case of an accidental release during the grazing period of dairy cows, the contaminative influence due to the inhalation of air was negligible.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.64-72
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• 2007

Humans are exposed by a range of pollutants in soil via exposure routes such as ingestion, inhalation, and dermal contact. Risk assessment is a process of evaluating the adverse health effects of chemicals as a result of exposure to stressors, and it is a very useful tool to establish the cleanup goals in contaminated lands. In the exposure assessment that is one of main process in risk assessment, exposure factor plays a significant role to quantify the intake of soil pollutants. However there is a very limited study about the exposure factor applicable to Korea. In this study, we compared the exposure factors applied by the developed countries including the United States and representative European countries, and suggested the exposure factor that might be suitable in our situation. The exposure factors considered in this study include average lifetime, body weight, (exposed) skin surface area, life time, skin absorption, soil-skin adherence factor, and soil ingestion rate. This information is needed to quantitatively estimate the intake of soil pollutants in contaminated lands.

• Journal of the Korean Geotechnical Society
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• v.23 no.9
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• pp.5-16
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• 2007

The simple linear elastic-perfectly plastic model with soil parameters $s_u,\;E_u$ and n of undrained condition is usually applied to predict the displacement of a constructed diaphragm wall(DW) on soft soils during excavation. However, the application of this soil model for finite element analysis could not interpret the continued increment of the lateral displacement of the DW for the large and deep excavation area both during the elapsed time without activity of excavation and after finishing excavation. To study the characteristic behaviors of soil behind the DW during the periods without excavation, a series of tests on soft Bangkok clay samples are simulated in the same manner as stress condition of soil elements happening behind diaphragm wall by triaxial tests. Three kinds of triaxial tests are carried out in this research: $K_0$ consolidated undrained compression($CK_0U_C$) and $K_0$ consolidated drained/undrained unloading compression with periodic decrement of horizontal pressure($CK_0DUC$ and $CK_0UUC$). The study shows that the shear strength of series $CK_0DUC$ tests is equal to the residual strength of $CK_0UC$ tests. The Young's modulus determined at each decrement step of the horizontal pressure of soil specimen on $CK_0DUC$ tests decreases with increase in the deviator stress. In addition, the slope of Critical State Line of both $CK_0UC$ and $CK_0DUC$ tests is equal. Moreover, the axial and radial strain rates of each decrement of horizontal pressure step of $CK_0DUC$ tests are established with the function of time, a slope of critical state line and a ratio of deviator and mean effective stress. This study shows that the results of the unloading compression triaxial tests can be used to predict the diaphragm wall deflection during excavation.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.191-192
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• 2003

원자력시설의 사고시 대기중으로 누출된 방사성물질에 의해 오염된 토양으로부터 재배된 농작물로 인한 인체노출은 각종 환경오염물질에 의한 인체영향 연구결과에 보듯이 직접적인 방사능에 의한 인체노출 못지 않게 상당히 중요하다. 이러한 섭식경로를 통한 노출은 각 나라마다 서로 다른 토양조건 및 작물체종류의 다양성등 다른 양상을 보이고 있어, 연구가 수행된 미국이나 유럽등지의 평가방법을 그대로 사용하면 국내의 토양에서 재배되는 농작물이나 이를 이용한 축산물에 따른 한국인의 독특한 섭취양상을 충분히 고려하여 평가하기 어려울 수 있다. (중략)

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.535-545
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• 2005

Environmental survey from some abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to arsenic influenced by past Au-Ag mining activities. Elevated levels of As were found in tailings from the studied mine areas. This high concentration may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters fur As have been used. The HQ values fer As via the rice grain and groundwater consumption were significantly higher compared with other exposure pathways in all metal mine areas. However, there were minimal soil and water dermal contact risks. The resulting Hl values of As from the Dongil, Okdong and Hwacheon mine areas were higher than 5.0, and their toxic risk due to drinking water and rice grain was strong in these mine areas. The cancer risk of being exposed to As by the rice grain route from the Dongil, Okdong and Hwacheon mine areas was $5.2\times10^{-4},\;6.0\times10^{-4}\;and\;8.1\times10^{-4}$, respectively. The As cancer risk via the exposure pathway of drinking water from these mine areas exceeded the acceptable risk of 1 in 10,000 fer regulatory purposes. Thus, the daily intakes of groundwater and rice grain by the local residents from the Dongil, Okdong and Hwacheon mine areas can pose a potential health threat if exposed by long-term arsenic exposure.