• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.472-472
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• 2004

Numerous studies on urban groundwater have been carried out in many other countries. Urban groundwater shows a unique hydrologic system because of complex urban characteristics such as road pavement, sewers and public water supply systems. These urban facilities may change the characteristics of groundwater recharge but contaminate its quality as well. There have been several researches on urban groundwater in Seoul. Seoul has been industrialized very rapidly so that the city has large population. The recent population in Seoul amounts to more than ten millions, corresponding to a very high density of about 17, 000 people/km$^2$. Therefore, many factors affect the groundwater quality and quantity in Seoul. Nowadays, groundwater in Seoul is being extracted for construction, industrial use, and drinking and so on. There are 15, 714 wells in Seoul and its annual usage is 41, 425, 977m$^3$(in 2001). Therefore, systematic studies are needed to properly manage and use the groundwater in Seoul. The purposes of this study in progress are to identify geochemical characteristics of groundwater in Seoul and to determine the extent of groundwater contamination and its relationship with urban characteristics. For this study, groundwater was sampled from more than 400 preexisting wells that were randomly selected throughout the Seoul area. For all samples, major cations together with Si, Al, Fe, Pb, Hg For 200 samples among them, TCE, PCE, BTEX were also analyzed by GC. Our study shows that groundwater types of Seoul are distributed broadly from Ca-HCO$_3$ type to Ca-Cl＋NO$_3$ type. The latter type indicates anthropogenic contamination. Among cations, Ca is generally high in most samples. In some samples, Na and K are dominant. The dominant anions change widely from HCO$_3$ to Cl＋NO$_3$. The anion composition is considered to effectively indicate the contribution of distinct anthropogenic sources. In addition, major ions are positively proportional to total dissolved solid (TDS) except K and NO$_3$. Thus, we consider that TDS may be used as an effective indicator of the extent of pollution. However, the increase of TDS may result from increased water-rock interaction. To determine the extent of groundwater contamination, it is needed to figure out the baseline water quality in Seoul. Furthermore, detailed geochemical studies are required to find out pollution sources and their corresponding hydrochemical parameters.

• Economic and Environmental Geology
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• v.34 no.6
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• pp.539-553
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• 2001

Geochemical data of the Han river water, including four tributary water samples in the main Han river are presented in this paper. The concentration of dissolved ions in the North Han river water decreases in order of Ca>Na>K>Mg and HCO$_3$>NO$_3$>SO$_4$>Cl, which it mainly affected by the chemical weathering of granite and gneiss in the drainage basin. Meanwhile, the South Han river water shows a decreasing order of Ca>Mg>Na>K and HCO$_3$>SO$_4$>NO$_3$>Cl, which is controlled by the bed rock geology of carbornate rooks and the inflow of acid mine drainage from the metal and coal mines in the Taebaegsan and Hwanggangri areas. The main Han river waters are characterized by unusually high concentration of Na, Cl and SO$_4$ (Ca>Na>K>Mg and HCO$_3$>SO$_4$>CI>NO), indicating a significant anthropogenic pollution by human activities in the metropolitan Seoul city. The geochemical data of the Han river waters from 1981 through 1996 to 1999 records a significant increase in SO$_4$ and NO$_3$, which responsible for the increasing arid mane drainage and municipal anthropogenic pollution.

• Environmental Engineering Research
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• v.15 no.2
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• pp.85-91
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• 2010

Romania aims to adopt and implement the European Union's legislation, also including that for the field of water management. Like other countries, groundwater in Romania is locally polluted from point sources, such as leaking landfills, as well as from diffuse pollution sources, include fertilizers, pesticides and leakages from sewers, in urbanized areas. Diffuse pollution can also occur indirectly, by over-exploitation of groundwater wells, resulting in salt water intrusion, as well as from mining and exploitation of mineral aggregates. Romania has quite an intensive monitoring scheme to measure groundwater quality in phreatic and confined aquifers. The purpose of the work resumed in this paper was to derive natural background levels (NBL) for groundwater in order to distinguish the natural elevated concentrations of some substances (natural phenomena) from point and diffuse pollution (anthropogenic phenomena). Based on these NBLs, threshold values (TV) for groundwater will be set according to the requirements of the European Water Framework Directive and the related Groundwater Directive. This paper describes the results of a study for the derivation of NBL and TV in a pilot Groundwater Body. Also, the process and draft results for extrapolating this work for all Romanian groundwater bodies is explained, as well as points for future consideration with respect to monitoring and management.

• Membrane and Water Treatment
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• v.13 no.5
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• pp.245-257
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• 2022

Water quality characteristics and their spatial variations in the Nakdong River were statistically analyzed by multivariate techniques including correlation analysis, CA, and FA/PCA based on water quality parameters for 17 sites over 2017-2019, yielding PI values for primary factors. Site 10 indicated the highest parameter concentrations, and results of pearson's correlation analysis suggest that non-biodegradable organic matter had been distributed on the site. Five clusters were identified in order of descending pollution levels: I (Ib > Ia) > II (IIa > IIb) > III. Spatial variations started from sub-cluster Ib in which Daegu city and Geumho-river are joined. T-P, PO4-P, SS, COD, and TOC corresponded to VF 1 and 2, which were found to be principal components with strong influence on water quality. Sub-cluster Ib was strongly influenced by NO3-N and T-N compared to other clusters. According to the PIs, water quality pollution deteriorated due to non-biodegradable organic matter, nitrogen- and phosphorus-based nutrient salts in the middle and lower reaches, illustrating worsening water pollution due to inflows of anthropogenic sources on the Geumho-river, i.e., sewage and wastewater, discharged from Site 10, at which there is a concentration of urban, agricultural, and industrial areas.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.117-118
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• 2003

대기 중 전체 오존의 약 10%를 차지하고 있는 대류권 오존은 대류권의 화학구성을 조절하고, 기후를 변화시키며 인체와 식물에 해로운 영향을 끼친다. 이러한 대류권 오존은 최근 동아시아에서 북반구의 다른 중위도 지역보다 더욱 크게 증가하고 있다(Lee et al., 1998). 아시아 대륙의 오존 증가는 지역적으로 국한된 것이 아니라 오존을 비롯해 오존의 전구 물질 수송으로 태평양과 심지어 북아메리카까지 영향을 미치는 것으로 관측되었다(Jacob, 1999). 그러므로 아시아 지역의 대류권 오존 분석과 원인을 규명하는 것이 중요하다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1996.10a
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• pp.60-63
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• 1996

Industrialization and urbanization of coastal areas in recent years have brought about a lot of coastal marine environmental problems. Water quality problems such as eutrophication or pollution by toxic chemicals are especially serious, threatening coastal ecosystems. These problems are mainly induced by anthropogenic loads of materials from the land. In order to design suitable counter measures, we should well understand the processes causing the problems. (omitted)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.183-184
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• 2000

도시화가 진행될수록 인구 집중과 고충 건물의 점유 증가를 초래하고 이로 인해 도심내 공장의 증가, 자동차의 폐열량 증가, 겨울철 연료와 여름철 냉방에 의한 에너지 사용량이 증가된다. 이때 방출된 열원으로 인해 도시 열섬의 강도는 커지게 된다. 단위면적에 대해 방출되는 열플럭스가 도시마다 큰 차이를 보이는데(Landsberg, 1981) 시드니 외곽부에 비해 도심내의 연간 에너지 사용량이 360배에 달한다는 것을 보였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.173-175
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• 2000

도시기상의 원인으로는 지표면 상태의 변화, 인공구조물과 인공열 방출을 들 수 있으며 그 외 오염물질 또한 하나의 원인이다. 도시의 낮은 함수률의 지표면 증가는 증발산 영역을 감소시켜 결과적으로 잠열방출을 감소시키고 현열을 증가시킨다(Tapper, et. al., 1981). 또한 도시의 배수시설은 유입된 강수의 흐름을 시골보다 짧은 기간 머무르게 하여 도시에서 낮은 절대 습도를 가지게 한다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.368-369
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• 2003

각종 배출원에서 배출된 입자상 물질은 대기 중 확산, 이동, 침착 등을 통해 국지적 도시오염 뿐만 아니라 장거리까지도 이동함으로서 광역적 대기오염의 원인이 되고 있는 등 입자상 물질의 발생원 추적에 관한 연구가 필요한 실정이다. 지금까지 입자상 물질의 발생원 추적은 대부분 배출원의 발생량 조사나 필터에 포집된 시료의 전체적인 화학적 분석의 개념으로 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화되고 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.220-221
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• 2000

도시화가 진행될수록 인구 집중과 고층 건물의 점유 증가를 초래하고 이로 인해 도심내 공장의 증가, 자동차의 폐열량 증가, 겨울철 연료와 여름철 냉방에 의한 에너지 사용량이 증가된다. 이때 방출된 열원으로 인해 인공열 배출량이 커지게 된다. 단위면적에 대해 방출되는 열플럭스가 도시마다 큰 차이를 보이는데(Landsberg, 1981) 시드니 외곽부에 비해 도심내의 연간 에너지 사용량이 360배에 달한다는 것을 보였다. (중략)