• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.587-597
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• 2005

This review deals with arsenic chemistry and its occurrence in groundwater. Specifically, the paper gives an overview regarding chemical and physical properties of arsenic species, oxidation of As(III), geochemical processes related to the fate and transport of arsenic, arsenic leaching from soil, and mechanism of arsenic leaching from arsenic-containing minerals.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.137-144
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• 2012

In order to monitor the pesticide residues in rice paddy soils and paddy waters in Korea and evaluate leachabilities to groundwater of the pesticides detected, paddy soils and paddy waters were collected twice from 40 sites of rice growing paddy fields in July and August in 2011, respectively. Pesticide residues in the samples were analyzed by multi-residue method with GC and HPLC. Five pesticides, such as butachlor, cypermethrin, iprobenfos, oxadiazon, and pendimethalin were detected from thirteen paddy soils and detection rate was about 16.3%, while no pesticide was detected in paddy water. As a results of the estimation of leachabilities for the pesticides detected using GUS (groundwater ubiquity score), their GUSs were less than 1.3, representing they have no potentials to leach into groundwater.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.78-91
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• 2007

The groundwater chemistry is heavily influenced by land use. This study has investigated the groundwater quality and contamination characteristic associated with land use. Contamination index ($C_d$) was estimated for evaluating and areal distribution of groundwater contamination degree. Groundwater samples collected from 216 locations in the study area show great variability in chemical composition. Electrical conductance ranges from 100 to $31,360\;{\mu}S/cm$. The pH values are between 4.6 (acidic) and 8.57 (weak alkaline). The water types predominantly represent the $Ca-HCO_3$ and $Ca-Na-HCO_3$ types, whereas, in the residential and business areas, the water type is shifted to (Na, Ca)-Cl type with rich concentration of Cl. The $C_d$ values of the study area range from 1.1 to 117.6 with a mean of 9.56.

• Journal of Soil and Groundwater Environment
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• v.20 no.1
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• pp.36-40
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• 2015

This study examined the disinfection in combined sewer overflows (CSOs) by pulsed ultraviolet (PUV). The reflectors (stainless steel. mirror, aluminium foil, aluminium (1050), aluminium (6061), aluminium (5052), and aluminium mirror) of PUV irradiation was performed in a 90 L stainless reactor at a constant temperature of $20^{\circ}C$ and an applied power of 4000 W. The reflection efficiency of reflectors were showed 1.00 (aluminium mirror) ~ 1.48 (aluminium foil) does. The case of a rough surface analysis using SEM showed high reflectance, was the case of a smooth surface and a low reflectivity. Pseudo first-order rate constant calculated results, has a higher reflectivity values were more than twice as high compared to the low reflectivity. Affected Total coliforms disinfection time, depending on the type of reflector is considered.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.281-297
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• 1993

Nitrogen is an element required to meet optimal plant growth. However, when it was applied (as chemical fertilizer or animal waste) more than the demand of plant and managed it unreasonably can be accumulated in subsoil and leached from soil system. Nitrogen also can be act as an pollutant to soil and water through water contamination if its concentration exceed the critical level. The concentration and downward movement of nitrate in soil is influenced by cultural practices and soil properties. High level of nitrate nitrogen in drinking water is harzadrous for animal and human health, especially for infants and the restoration of the quality of groundwater is impossible by now. Therefore it is the only way to prevent from leaching of nitrate nitrogen to keep the quality of groundwater as vital water resource. The aims of the presentation of this review paper are to understand the relationship between agricultural practices and the concentration of nitrate nitrogen in groundwater and to suggest further informations for the rational management methods to reduce the leaching of nitrate nitrogen in soil.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.303-314
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• 2020

Bottled water companies submit monthly hydrologic data including periodical environmental effects investigation, daily water production capacity, water production, water level, water chemistry (pH, EC, temperature) per hour and strictly manage groundwater by periodical analyses. Thus few problems concerning drawdown due to excess intake of groundwater take place. Nevertheless, bottled water companies are imprinted as a contribution to civil affairs resulted regarding groundwater near the companies. Therefore, a new method is required during water balance analysis in environmental effects evaluation, which should be compatible with the evaluation by hydrologic experts as well more accessible to non-experts. In this study, water level of surface water and recharge rate in subcatchment where water production wells are located were measured and monthly baseflow rates were separated from normal streams. Besides, recharge properties of groundwater and surface water in the same catchment area were estimated using analyses of oxygen and hydrogen isotopes in groundwater (production well), surface water, and rainfall.

• The Journal of Engineering Geology
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• v.14 no.4 s.41
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• pp.469-485
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• 2004

The purpose of this study is to investigate the hydrochemical characteristics of groundwater in the Umsung area, and to elucidate the effect of host rock type, well depth and mineralization zone on the groundwater chemistry. The geology of the study area consists of Jurassic granite and Cretaceous sedimentary rocks, which are bounded by a fault. Most of shallow groundwaters exploited in the Jurassic granite area are used for agricultural purpose, whereas the deep groundwaters in the Cretaceous sedimentary rocks are used for a drinking water. The shallow groundwater shows weak acidic pH, the electrical conductivity ranging from $142\;to\;903\;{\mu}S/cm$, and the chemical type of $Ca-HCO_3\;to\;Ca-Cl(SO_4,\;NO_3)$. A few of shallow groundwaters are contaminated by nitrate, and show high concentration of Fe, Mn and Zn, that reflects the effect of a mineralization zone. The deep groundwater shows neutral to weak alkaline pH, higher electrical conductivity than that of shallow groundwater, and the chemical type of $Ca-HCO_3$. The seepage water from the abandoned mines does not have the characteristics such as acidic pH, high concentration of heavy metals and high sulfate content. The hydrogen and oxygen isotopes of groundwater indicates an altitude effect of the recharge area between deep groundwater and shallow groundwater. In conclusion, the chemical composition of groundwater complicately reflects the effects of their host rocks, well depth, agricultural activity and mineralization zone in the study area.

• Proceedings of the KSEEG Conference
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• 2000.04a
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• pp.119-120
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• 2000

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.11-11
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• 2000

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.12-12
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• 2000