• Journal of Environmental Science International
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• v.22 no.5
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• pp.639-649
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• 2013

Over 96.2% of the agricultural water in Jeju Island is obtained from groundwater and there are quite distinct characteristics of agricultural water demand/supply spatially because of regional and seasonal differences in cropping system and rainfall amount. Land use for cultivating crops is expected to decrease 7.4% (4,215 ha) in 2020 compared to 2010, while market garden including various vegetable crop types having high water demand is increasing over the Island, especially western area having lower rainfall amount compared to southern area. On the other hand, land use for fruit including citrus and mandarin having low water demand is widely distributed over southern and northern part having higher rainfall amount. The agricultural water demand of $1,214{\times}10^3\;m^3/day$ in 2020 is estimated about 1.39 times compared to groundwater supply capacity of $874{\times}10^3\;m^3/day$ in 2010 with 42.4% of eastern, 103.1% of western, 61.9% of southern, and 77.0% of northern region. Moreover, net secured amount of agricultural groundwater would be expected to be much smaller due to regional disparity of water demand/supply, the lack of linkage system between the agricultural water supply facilities, and high percentage of private wells. Therefore, it is necessary to ensure the total net secured amount of agricultural groundwater to overcome the expected regional discrepancy of water demand and supply by establishing policy alternative of regional water supply plan over the Island, including linkage system between wells, water tank enlargement, private wells maintenance and public wells development, and continuous enlargement of rainwater utilization facilities.

• Biomedical Science Letters
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• v.29 no.2
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• pp.81-87
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• 2023

Pan-Enterovirus (Pan-EV) infects millions of children and infants worldwide every year. As severe infections have recently been reported, the need for monitoring has consequently intensified. Pan-EV is a categorical name for waterborne enteroviruses belonging to the Picornaviridae family, and includes a wide range of pathogens including Coxsackievirus (CoxV), Echovirus (EcoV) and Enterovirus (EV). In this study, we proposed an optimal RT-nested PCR method for diagnosis of various types of Pan-EV in an aquatic environment and developed a positive control. Considering detection sensitivity, specific reaction, and final identification, one condition capable of amplifying 478 bp among the four candidates in the 1^st round PCR (RT-PCR) and one condition in the 2^nd round PCR (nested PCR) were selected. Through the detection of nucleic acids extracted from 123 groundwater samples and the detection sensitivity test based on artificial spiking in the sample, the methods are optimal for non-disinfected water samples such as groundwater. We developed a positive control for Pan-EV detection that can be amplified to different sizes under the two conditions. Accuracy could be further improved by testing for contamination from the control group. The method proposed in this study and the positive control developed are expected to be used in monitoring Pan-EV in aquatic environments including groundwater through future research using more samples.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.93-97
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• 2002

This research introduces some preliminary results of bank filtering intake method adopted in Dalseo area, Nakdong River. This intake method has been planned to supply water resources of 41,000 ㎥/day to Goryeong-Gun and Seongju-Gun in 2016. It is believed that the bank filtering intake method can afford to supply 41,000 ㎥/day amount of water resources and that the raw water quality using the method has more advantages in water treatment than direct surface water intake. Even though the safety yield about individual vertical well is roughly estimated to about 2,000 ㎥/day, it is desirable to decrease the safety yield to about 1,000 ㎥/day in the consideration of long term and simultaneous well pumpings and other unknown factors. Ongoing study will give basic data and new techniques to solve the problems appearing in application of bank filtering method as well.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.148-154
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• 2002

Groundwater Dam is one of the reliable techniques to get huge amount of groundwater abstraction for municipal, agricultural, drinking, industrial water supply system. It can be a major technique to solve water shortage problems when it based on the sufficient watershed, proper topology, and adequate aquifer distribution and pollution control. It is suggested that the two consecutive underground wall in the coastal area to prevent seawater intrusion beneath a single wall.

• Journal of Korea Water Resources Association
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• v.51 no.11
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• pp.1011-1020
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• 2018

This study aims to develop a drought monitoring scheme based on groundwater which can be exploit for water supply under drought stress. In this context, groundwater level can be used as a proxy for better understanding the temporal evolution of drought state. First, kernel density estimator is presented in the monthly groundwater level over the entire national groundwater stations. The estimated cumulative distribution function is then utilized to map the monthly groundwater level into the standardized groundwater level index (SGI). The SGI for each station was eventually converted into the index for major cities through the Thiessen polygon approach. We provide a drought classification for a given SGI to better characterize the degree of drought condition. Ultimately, we conclude that the proposed monitoring framework enables a more reliable estimation of the drought stress, especially for a limited water supply area.

• KIEAE Journal
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• v.17 no.3
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• pp.119-124
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• 2017

Purpose: Groundwater heat pump (GWHP) system has high coefficient of performance than conventional air-source heat pump system and closed-loop type geothermal system. However, there is problem in long-term operation that groundwater raise at the diffusion well and reduced at the supply well. Therefore, it is necessary to accurately predict the groundwater flow, groundwater movement and control the groundwater level in the wells. In this research, in consideration of hydrogeological characteristic, groundwater level and groundwater movement were conducted analysis in order to develop the optimal design method of the two-well system using the pairing pipe. Method: For the optimum design of the two-well system, this research focused on the design method of the pairing pipe in the simulation model. Especially, in order to control the groundwater level in wells, pairing pipe between the supply well and diffusion well was developed and the groundwater level during the system operation was analyzed by the numerical simulation. Result: As the result of simulation, the groundwater level increased to -2.65m even in the condition of low hydraulic conductivity and high pumping flow rate. Consequently, it was found that the developed system can be operated stably.

• Journal of Soil and Groundwater Environment
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• v.20 no.2
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• pp.1-9
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• 2015

Groundwater has been a very precious resource for human life and economic development in the world. With increasing population and food demand, the groundwater use especially for agriculture is largely elevated worldwide. The very much large groundwater use results in depletion of major aquifers, land subsidences in many large cities, anthropogenic groundwater contamination, seawater intrusion in coastal areas and accompanying severe conflicts for water security. Furthermore, with the advent of changing climate, securing freshwater supply including groundwater becomes a pressing and critical issue for sustainable societal development in every country because prediction of precipitation is more difficult, its uneven distribution is aggravating, weather extremes are more frequent, and rising sea level is also threatening the freshwater resource. Under these difficulties, can groundwater be sustaining its role as essential element for human and society in the near future? We have to focus our efforts and wisdom on answering the question. Korean government should increase its investment in securing groundwater resources for changing climate.

• Journal of Soil and Groundwater Environment
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• v.29 no.3
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• pp.23-36
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• 2024

Miryang City, the study area, has a water supply rate of 87.4%, which is 12% lower than the national water supply rate of 99.4%, but has a high dependence on groundwater due to the high ratio of farms. In agricultural areas, contamination becomes relatively more critical, requiring significant attention to the management and conservation of groundwater resources. This study aims at estimate groundwater vulnerability of Miryang City using the DRASTIC index map, Piper diagram, and water quality data to correlated with the DRASTIC index. The results from DRASTIC map were divided into five classes: very high, high, moderate, low, and very low. The areas in central and southern part of study area, which are characterize by a very high index with [Ca-Cl] and [Na-Cl] water types, covering a large alluvium with the Miryang River and Nakdonggang River. In addition, a correlation analysis between groundwater quality parameters and the DRASTIC index was carried out. Chloride, sodium, and sulfate ions showed a weak relationship with DRASTIC index, with correlation coefficient was 0.507, 0.487 and 0.344, respectively. These results suggest that aquifer media, soil media, hydraulic conductivity, and chloride ion are important factors for groundwater vulnerability.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.369-372
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• 2004

This study presents the hydrogeochmical investigation to know the effect of geology and sources for water quality in small potable water supply system at rural area. The results of water quality in Geumsan area showed the 3.2% of water samples exceeded the limit of drinking water standard by bacteria. The hydrochemical investigation results indicated the high EC, Ca and HCO$_3$ in surface water and metasedimentary rocks and this is caused by the dissolution of calc-slicate minerals of metasedimentary rocks.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.176-185
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• 2021

This paper aims to develop a new paradigm for groundwater management which is compatible with integrated water management policies in Korea. Three key roles of groundwater are defined for addressing water cycle distortion, high water stress, water quality degradation, aquatic ecosystems deterioration, and water-related hazards. Firstly, groundwater plays an important role in contributing soundness of water cycle as a component of water cycle. Secondly, it is a local water resource to ensure water supply sustainability. Thirdly, groundwater is an essential water resource for drought and emergencies. In order to support the groundwater roles, we propose a paradigm shift for groundwater management and policy directions towards integrated water management. The new paradigm consists of managements for sound water cycle on a watershed scale and groundwater environment(quantity, quality, and groundwater dependent ecosystems) managements for both human and nature. A prospective management also constitutes the new paradigm. In addition, this paper proposes four policy directions in groundwater management. The policies emphasize the integrated management of groundwater and surface water, management of groundwater environment(quantity, quality, and groundwater dependent ecosystems), management of groundwater uses for water sustainability and security, and enhancement of groundwater publicity.