• Journal of Soil and Groundwater Environment
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• v.18 no.3
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• pp.23-32
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• 2013

Korean groundwater quality standards were established in 1994, and revised in 2003 and 2010. The substances for which standards have been developed are classified into two groups, general pollutants, 4, and specific pollutants, 15. The standards have been applied to household water use, agriculture, aquaculture, and industrial use. However, there is no systematic methodology for either selecting candidate substances or establishing groundwater standards. We investigated various derivation methodologies for groundwater standards used by the European Commission and 27 member states and compared their methods for determining threshold values. The European Commission presented to their member states groundwater standards for two substances and a list of required substances for derivation of threshold values along with the member states. Interestingly, they first considered national background levels and then considered other criteria for water protection, such as drinking water standards, environmental quality standards, and irrigation standards. We suggest that Korean background levels in groundwater should be included in the methodology for establishing groundwater quality standards. These results may be useful in developing a systematic methodology for establishing Korean groundwater quality standards.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.195-198
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• 2002

Nitrogen pollution in urban and rural groundwater is a common problem and poses a major threat to drinking water supplies based on groundwater. In this work, the kinetics of nitrification-denitrification coupled reactions are modeled and new reaction modules for the RT3D code (Clement, 1997) describing the fate and transport nitrogen species, dissolved oxygen, dissolved organic carbon, and biomass are developed. The proposed nitrogen transformations and transport model showed very good match with results of a conceptual model. However, the model simulation results for the major reactive species should be tested for validation using experimental and field data.

• International Journal of Contents
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• v.8 no.2
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• pp.60-66
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• 2012

This study was designed to detect and measure the concentration of radioactivity of natural radionuclides ($^{238}U$, $^{232}Th$, $^{40}K$) and artificial radionuclides ($^{137}Cs$, $^{60}Co$) present in the drinking water of the city of Busan and surrounding areas in South Korea, and also to measure the absorbed dose of radiation caused by these elements in the residents so as to help better manage the risk that these radionuclides pose in the future. For the purposes of the study, a total of 42 samples of water were collected from three key water sources (19 samples of groundwater, 4 samples of tap water, and 19 samples of surface water) and their contents were analyzed for radioactivity concentration. The results revealed that two natural radionuclides, $^{238}U$ and $^{232}Th$, exist in the groundwater with an average concentration of radioactivity of 3.34 Bq/L and $8.28{\times}10^{-5}Bq/L$ respectively, while the surface water was found to contain the same two radionuclides with mean concentrations of 0.849 Bq/L and $1.103{\times}10^{-4}Bq/L$ respectively. In addition, of the 19 samples of the groundwater, $^{137}Cs$ was found in eight of them and $^{60}Co$ was detected in ten. Of the four samples of the tap water, $^{137}Cs$ was detected in all samples and $^{60}Co$ was detected in three. Both $^{137}Cs$ and $^{60}Co$ were detected in all 12 samples of surface water. As far as $^{40}K$ is concerned, this element was detected in three of the 19 groundwater samples, but was not detected in any surface or tap water sample. In addition, the absorbed dose of $^{238}U$ from the groundwater was $7.94{\times}10^{-8}Sv/y$, while the absorbed dose of $^{232}Th$ from the surface water was $9.33{\times}10^{-13}Sv/y$. The absorbed dose of $^{137}Cs$ from the tap water was $7.33{\times}10^{-5}Sv/y$, while the absorbed dose of $^{60}Co$ from the surface water was the highest at $4.23{\times}10^{-6}Sv/y$.

• Journal of Environmental Science International
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• v.26 no.10
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• pp.1135-1146
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• 2017

At riverbank filtration sites, groundwater levels of alluvial aquifers near rivers are sensitive to variation in river discharge and pumping quantities. In this study, the groundwater level fluctuation, pumping quantity, and streamflow rate at the site of a riverbank filtration plant, which produces drinking water, in the lower Nakdong River basin, South Korea were interrelated. The relationship between drawdown ratio and river discharge was very strong with a correlation coefficient of 0.96, showing a greater drawdown ratio in the wet season than in the dry season. Autocorrelation and cross-correlation were carried out to characterize groundwater level fluctuation. Autoregressive model analysis of groundwater water level fluctuation led to efficient estimation and prediction of pumping for riverbank filtration in relation to river discharge rates, using simple inputs of river discharge and pumping data, without the need for numerical models that require data regarding several aquifer properties and hydrologic parameters.

• Mycobiology
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• v.50 no.5
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• pp.345-356
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• 2022

The fungal distribution, diversity, and load were analyzed in the geographically segregated island groundwater systems in Korea. A total of 79 fungal isolates were secured from seven islands and identified based on the internal transcribed spacer (ITS) sequences. They belonged to three phyla (Ascomycota, Basidiomycota, and Chlorophyta), five classes, sixteen orders, twenty-two families, and thirty-one genera. The dominant phylum was Ascomycota (91.1%), with most fungi belonging to the Cladosporium (21.5%), Aspergillus (15.2%), and Stachybotrys (8.9%) genera. Cladosporium showed higher dominance and diversity, being widely distributed throughout the geographically segregated groundwater systems. Based on the diversity indices, the genera richness (4.821) and diversity (2.550) were the highest in the groundwater system of the largest scale. As turbidity (0.064-0.462) increased, the overall fungal count increased and the residual chlorine (0.089-0.308) had low relevance compared with the total count and fungal diversity. Cladosporium showed normal mycelial growth in de-chlorinated sterilized samples. Overall, if turbidity increases under higher fungal diversity, bio-deterioration in groundwater-supplying facilities and public health problems could be intensified, regardless of chlorine treatment. In addition to fungal indicators and analyzing methods, physical hydrostatic treatment is necessary for monitoring and controlling fungal contamination.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.4
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• pp.215-222
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• 1998

The objective of this study was to investigate the effects of physico-chemical environmental factors on the changes of bacterial population from two sites used for drinking water and eight sites polluted with various pollutant in Seoul city. In all the stations except for two sites used for drinking water, the concentrations of nitrate- nitrogen and ammonia were in excess of the criteria of groundwater quality by the result of analysis of 40 variations including physicochemical environmental factors, heavy metals, and bacterial populations. The numbers of total bacteria, heterotrophic bacteria and functional groups of bacteria were ranged from 5.1 to 41.4${\times}$10$\^$5/cells/ml and from 0.01 to 29.6${\times}$10$^4$cfu/ml, respectively. The activities of extracellular enzymes showed the ranges of 0.005∼11.3${\mu}$M/l/hr and its order to lipase, phophatase, ${\beta}$-glucosidase, cellulase, chitinase, amylase. The results of correspondence and multidimensional scaling analysis between bacterial populations and its physico-chemical environmental factors were explained the effects of physico-chemical environmental factors according to site characters and separated four group, which is accord with potential pollutants at wells.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.87-92
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• 1995

In the Vicinity of the Sindae-dong waste disposal site in Taejon, the average Cu, pb and Zn concentrations in soils are higher than those in other Korean soils but these are not high enough to cause any harmful effect to human and animal through the crop plants. Copper, Pb and Zn are not detected in the groundwater samples and F, Cl, $NO_2$, $NO_3$ and $SO_4$ concentrations in groundwater samples are lower than drinking water standards. However, the pH of groundwater sample in site D is 5.58 which is not suitable for the drinking water. With the electric resistivity method, the water-containg layers are found in contaminated soils and the resistivity values are considerably low because of the dispersion of plume by the leak of leachates. According to the results from the magnetic survey method, the anomalous values of the total geomagnetic fields and their gradients are found in the sampling site of low resistivity and high trace element concentrations.

• Journal of Soil and Groundwater Environment
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• v.14 no.5
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• pp.51-61
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• 2009

This study was performed to research the characteristic of radionuclides of 80 groundwater monitoring networks in Busan. According to the research, average concentration of Uranium was $4.33\;{\mu}g/L$, maximum concentration of Uranium was $171.55\;{\mu}g/L$ among the 80 sampling sites. One sample exceeded the Proposal standard of drinking water in USA in Uranium ($30\;{\mu}g/L$) and four samples exceeded the recommendatory value of WHO about Uranium ($15\;{\mu}g/L$). Radon and gross-$\alpha$ concentration of all samples were far less than the Proposal standard of drinking water in USA. In this study average concentration of radionuclides in underground water wasn't too high, but needed to control the concentration of them to prevent exposure to the people. And it needs to be taken measures in some sites with high concentration of Uranium by closing the pipe line or etc through more studies.

• Clean Technology
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• v.26 no.1
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• pp.39-54
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• 2020

This study analyzed the groundwater quality according to the depth and geological features in Gyeongsangnam-do area using groundwater quality monitoring network data to grasp the groundwater quality characteristics and to provide basic data for policy making on efficient groundwater management. Five hundred and three data sets were acquired from background water quality exclusive monitoring network in soil groundwater information system for five years (2013 ~ 2017). Except for the total coliforms and tracer items such as mercury, phenol, and others, the parameters of water quality were significant or very significant, depending on depth and geological features. As the depth got deeper, the average value of pH and electrical conductivity increased; water temperature, dissolved oxygen, oxide reduction potential, arsenic, total coliforms, and turbidity decreased; and total unfit rate for drinking water standards was lower. It was found that the sum of the positive and negative ions was the highest in the clastic sedimentary rock and the lowest in metamorphic rock. The total unfit rate for drinking water standards was the highest for metamorphic rocks, followed by clastic sedimentary rock and unconsolidated sediments and, finally, intrusive igneous rock with the lowest penetration. The Na-Cl water type, which indicated the possibility of contamination by external pollutants, appeared only at some points in shallow depths and in clastic sedimentary rocks.

• Membrane Journal
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• v.18 no.3
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• pp.241-249
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• 2008

This study is to concentrate vanadium in Jeju groundwater using reverse osmosis processes, and to utilize the concentrate for vanadium water. Groundwater samples were taken from Wahyul, Ayum, and Seogwipo groundwater wells with different in vanadium content each other. Their vanadiuln concentrations were 31.8, 44.5, and 53.0 ppb, respectively. The rejection coefficients of every component in groundwater were increased with the increase of TMP At the TMP of $8 kg_f/cm^2$, the rejection coefficients of vanadium, sodium, potassium, aluminium, iron, and barium were $97.4%{\sim}99.0%,\;97.7%{\sim}97.8%,\;98.0%{\sim}98.3%,\;94.8%{\sim}97.5%,\;88.0%{\sim}96.4.0%$, and $97.9{\sim}98.0%$, respectively. And those of magnesium, calcium, chromium, mauganese, and strontium in three groundwater were more than 99.0% at the same TMP. It was possible that vanadium contents of Wahyul, Ayum and Seogwipo groundwater were concentrated into 58.6, 118.9, and 165.1 ppb, respectively, by 6 stages treatment at the recovery ratio of 15%. And these concentrated water (vanadium water) did not exceed the permissible drinking water standards.