• 한국물환경학회지
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• 제27권2호
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• pp.200-209
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• 2011

The purpose of the study is to optimally manage sewage treatment plant with analysis of phosphorus contribution and improvement of water quality contributing rate in the effect of inflowing point of effluent and Pal-Dang lake after reducing T-P discharge from large scale public sewage treatment plant at upstream of Pal-Dang lake. Also, this study, for enforcement of T-P in effluent, plans optimal management of effluent T-P through examining propriety of environmental, technological, and economical aspect such as water quality standard of domestic and foreign T-P and related policy. In regarding optimal management of T-P discharged from public sewage treatment plant located in upstream of Pal-Dang lake, the study drew following conclusions. With the optimal management of public sewage treatment plant, it showed that a pollution level became higher in the order of Sumgang E in South-Han river, C in Dalcheon, B1 B2, A in North-Han river, and J in Kyungancheon, and it is required reduction of T-P first. The highest value in analysis of benefit-costs from sewage treatment plant in the selected research area was Kyungan B, and the others are with the order of Jojong A, Bokha A, Kyungan A, and Yanghwa A. With result of this study, all 14 areas are required more enforced phosphorus treatment. The study resulted that the most top priority areas were Hangang F, Sumgang B, and Gyungan A, top priority areas were Bokha A, Dalcheon B, and Cheongmi A, priority areas were Hangang E, Heukcheon A, Gyungan B, and Jojong A, and potential areas were Sumgang A, Yanghwa A, Dalcheon A, and Hangang D. It seems to be appropriate to apply 0.2 mg/L of T-P treatment for water supply source reservation, 0.5 mg/L for the other areas by locally, and 0.2~0.5 mg/L for biological nitrogen phosphorus treatment method and 0.5~1 mg/L for Conventional Activated Sludge by technologically. Also, it may be appropriate to apply 0.2 mg/L for the most top priority area(I), 0.3 mg/L for the top priority area(II), 0.4 mg/L for priority area(III), and 0.5 mg/L for potential area(IV) by the separation of priority area.

• 한국환경과학회지
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• 제31권5호
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• pp.373-388
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• 2022

This study analyzed the temporal and spatial characteristics of water quality for five hydropower dam reservoirs in South Korea. Water temperature, pH, dissolved oxygen, and chlorophyll-a (Chl-a) showed high fluctuations in summer and autumn at all reservoirs, indicating the existence of seasonal effects. At all five reservoirs, the concentrations of suspended solids (SS) and total nitrogen (TN) fell under the "slightly bad" category and those of total organic carbon (TOC) fell under the "slightly good" category or higher, according to "the standard for living environment of lake water quality." Variations in the concentration ranges and degrees of change in SS, TN, and TOC among reservoirs were observed, indicating the influences of rainfall, surrounding environments, and seasonal changes. Daecheong and Namgang Dam showed high Chl-a concentrations in summer, indicating that the metabolism of microbial communities, such as algae, was active.

• 한국환경과학회지
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• 제19권1호
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• pp.39-45
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• 2010

When the Juam multipurpose dam which is connected with existing large water supply facilities is finished, water environment is changed from stream to lake. The changed quality of water should be examined. In this study, the result of water quality forecasting is analysed and an effective management plan of water quality is presented. Tn this study, the WASPS model that is a dynamic water quality simulation model was selected to forecast the water quality. This model forecasts movement of change of pollutants. For an application of the model, the subject areas were divided into seventeen sub-areas by considering change temperature depending measuring points and on depth of water. Meteorological data collected by the meteorological observatory and data about quality measured by the Korea Water Resources Development Corporation were used for an operation of the model. As a result of quality examination through quality data and estimated pollutant loading, the water quality environment criterion was grade II and the nutritive condition was measured as meso-graphic grade. In this study, an effective management was planned to improve water quality by reducing pollution load. According to the result of examination, when more than 30% of BOD was reduced it was recorded that the environment standard of water quality was improved to the second grade.

• 자원환경지질
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• 제33권6호
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• pp.505-517
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• 2000

This study was undertaken to provide a drinking water quality on the basis of physicochemical properties. In this study, the 25 samples of supply waters of the Taejon area were sampled twice (February and August in 1999). Hydrochemistry of the supply water belongs to the $Ca^{2＋}$-${HCO_3}^{-1}$ type, whereas the supply water was characterized by the relatively significant enrichment of ${Ca}^{2+}$, ${Na}^{2+}$, ${K}^{2+}$, ${Cl}^{2+}$ ions and heavy metals compared to the original water from the Daecheong lake. Generally, the supply water has a mean values for $10.7^{\circ}C$ of temperature, 6.86 of pH, -12 mV of Eh, 88 ${\mu}S$/cm of EC and 70.379 mg/l of TDS in February, whereas the waters of the same sites in August are a slightly high temperature ($26.1^{\circ}C$), TDS (78.069 mg/l) and extremely high EC (442 ${\mu}S$/cm) value. These values are similar with physicochemical properties of the original lake water depending on the seasonal differences. Results of speciation calculation indicate that potentially toxic ions might exist mainly in the forms of free metal (${Cu}^{2+}$ or ${Zn}^{2+}$) and a small amount of ${CO_3}^{2-}$and ${OH}^{-}$in the supply water. The water seemed to be in equilibrium with kaolinite field of the normal stability diagrams for the natural water. Based on enrichment parameter of the supply water normalized by original lake water composition, the average value of those parameter can be calculated with nearly 1.00, but the those values for Cu＋Zn possible source of decrepit pipe lines are 126.75 in February and 115.63 in August samples. The parameter values varied with sampling sites, however, do not exceed by chemistry of drinking water standard. Solid compounds remained on the membrane filter papers after filtration are adhered to pale yellow or yellowish brown colored dissolved solids and precipitates, which are coated by 0.02 to 0.35 mm thick per 500 ml with colloidal particles of about 1 to 2${\mu}m$ size. The particles are mainly Fe-Cu-Zn compounds and partly detected to Mn and Pb.

• 한국물환경학회지
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• 제27권1호
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• pp.110-114
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• 2011

In this paper, in order to eliminate Limnoperna fortunei inhabiting the water conduction pipeline, prechlorination at the intake station was employed to improve the degradation of water quality due to the high pH of raw water taken at the downstream of Paldang Dam, algal growth, etc.. With the prechlorination concentration of 1.0mg/L at the intake station, the pH in the water well at the treatment plant decreased by 0.4, and with 1.5mg/L, by 0.6. Also, it eliminated Chlorophyll-a by about 95%, and the population of algae by about 49%. Such disinfection by-products (DBPs) as Trihalomathanes (THMs), Haloacetic Acids (HAAs), and Chloral Hydrate (CH) were under the quality standard for potable water, showing no change by the prechlorination, while raising the prechlorination rate from 1.0 up to 1.5mg/L, the DBPs in the water well increased by 1.5 to 3.1 times. As a consequence of testing Kyungan Stream, a branch stream flowing into Lake Paldang, the prechlorination (0.57mg/L, 1.14mg/L, 1.71mg/L) had no effect of eliminating the taste and odor compounds and total organic carbon (TOC) which is the DBPs precursor. As for the efficiency of Geosmin elimination by the rates of prechlorination and powder activated carbonation (PAC), it was found that the higher the concentration of PAC was (30ppm>20ppm>10ppm), the higher the efficiency was; the higher the rate of prechlorination was, the lower the efficiency by PAC was. Therefore, when taste and odor occur from raw water, suspending prechlorination at the intake or lowering the rate was proved to be more effective in eliminating the taste and odor compounds by PAC.

• 대한환경공학회지
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• 제37권9호
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• pp.533-541
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• 2015

일본의 "유역별 하수도정비종합계획"(이하 '유총계획') 및 비와호 유역하수도를 소개하고 이를 바탕으로 국내에서 2013년도부터 수립 시행되고 있는 "유역하수도정비계획"의 발전방향 등을 제시하였다. 일본의 유총계획은 환경기본법에서 정하는 수질환경기준을 준수하기 위한 계획으로 비와호의 경우는 지자체의 조례에 의한 가중 배수기준보다 더 엄격한 기준을 적용하여 수립 시행하고 있는 것으로 분석되었다. 특히 비와호의 경우는 응집제첨가다단소화탈질법 등의 고도처리공법을 건설초기단계부터 적용하여 방류수의 수질항목별 농도가 BOD 0.9 mg/L, SS 0.6 mg/L, T-N 5.5 mg/L, T-P 0.06 mg/L였으며 BOD의 처리효율은 99.5%로 매우 높았다. 도입초기단계인 국내 유역하수도계획의 발전을 위해서는 평가항목의 다양화, 비용최소화, 건설 및 유지 보조금제도 개선, 경제적 개념의 배출부하량조정시스템의 도입, 유역하수도 개념 적립 등의 적용 방법 등을 장기적인 관점에서 연구할 필요가 있다.

• 생태와환경
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• 제39권3호통권117호
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• pp.285-295
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• 2006

본 연구에서는 (1) 선진외국 및 기타국가의 농업용수 수질기준을 검토하고 (2) 선진외국과 국내의 농업용수 수질기준을 항목별로 심층 비교 분석하여, 현행 농업용수 수질기준의 적정성을 평가하였다. 또한 (3) 국내 농업용수 수질기준의 문제점을 파악하고 추가로 기준설정이 요구되는 수질기준 항목을 도출하였다. 우리나라의 농업용수 수질기준은 따로 마련되어 있는 것이 아니라, 수질환경기준의 4등급에 해당하는데, 이는 관리목적의 기준으로 이수목적의 농업용수로 필요한 항목들이 누락되어 있는 실정이다. 예를 들어 캐나다의 경우 농약과 비료에 의한 오염 등을 고려하여 관개용수 수질기준을 제시하고 있으며 일본의 경우 우리나라와 달리 EC, Zn, 그리고 Cu항목을 설정해 두고 있다. FAO에서도 주요항목으로 염도와 토양 침투율 그리고 특정이온의 독성에 대해 제시하고 있으며 중국의 경우 벼에 대한 농업용수 수질기준을 따로 제시하고 있는 실정이다. 국내 농업용수 수질기준의 추가항목 필요성은 수질환경기준의 8항목과 사람의 건강보호항목 9항목으로 나누어 세밀하게 검토한 결과, 국내 농업용수 수질기준에 추가되어야 할 수질항목으로 나트륨, 전기전도도, 미생물항목. 그리고 5개의 미량원소 (염소, 붕소, 구리, 철, 아연)가 제안되었다. 전기전도도 (EC) 는 염도의 지표로 식물뿌리 주변에 염농도가 높으면 수분결핍과 이온 독성을 나타낸다. 하수처리수를 재이용하여 농업용수로 이용할 경우 분변성 오염은 공중위생상 문제가 되며 병원성 미생물의 공존가능성을 시사하기 때문에 미생물항목이 필요하다. 또한, 염소, 붕소, 구리, 철, 아연의 5개의 원소는 이미 선진국에서는 기준설정이 되어 있는 수질항목들로, 식물생장에 필수원소들이지만 일정량 이상이 되면 식물독성을 유발하는 원소로 제시되었다. 우리나라의 농업용수 수질기준이 농작물을 보호하고, 나아가 인체건강을 고려하는 실질적인 이수목적의 기준이 되기 위해서는 추가로 제안된 수질항목들에 대한 기준이 선정된 필요가 있는 것으로 사료된다.

• 한국관개배수논문집
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• 제18권1호
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• pp.4-17
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• 2011

The standard design methodology was suggested to construct wetland system for reducing non-point source pollution from Saemangeum reclaimed paddy land. To set for the design flow and concentrations, runoff and water quality survey were conducted during the irrigation period in 2008 at Gyehwa reclaimed paddy land located at near Saemangeum lake. It is rational that 1ha is the optimum constructed wetland size. To meet this size, the moderate drainage area of reclaimed paddy field was 50ha under the conditions that rainfall is 30mm, average runoff coefficient is 0.83, and runoff capture ratio is 0.6. At these condition, the runoff volume from 50ha was 10,520 $m^3/d$ including base flow during irrigation period. To select the optimum wetland system, several case studies were conducted by focusing on the tidal reclaimed land areas having wetland systems in Seokmun. Pond-Wetland system was selected as the standard model because of showing the highest reduction efficiency. Single variable regression equation were delivered to estimate effluent water concentrations from the designed wetland by using long-term monitoring data from the Seokmun experiment site. The effluent concentration from the designed wetland using these equation were showed moderately range.

• 한국습지학회지
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• 제13권3호
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• pp.643-655
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• 2011

본 연구는 소양호 상류 유역의 지류 하천을 대상으로 부착조류의 생물학적 지수의 수질 대표성을 검토하였으며 총체적인 수질환경평가를 시도하였다. 북한강 상류의 4개 수계에 대한 하천(북천-한계천, 내린천, 인북천, 소양강)에서 배수구역을 중심으로 총 9개 지점을 조사 지점으로 선정하여 현장조사를 하였다. 하천 주변의 토지 이용은 농경지중심과 임야 중심으로 뚜렷한 분포차이를 보였고, 소양강 상류 하천 유역은, 농경지 중심 지역에서는 오염된 수역의 대표종인 남조강이 높은 출현률을 보였고, 임야 중심 지역에서는 남조강, 녹조강, 규조강이 비교적 고르게 출현하였다. 따라서 오염원의 분포와 부착조류의 현존량 및 군집 분포는 밀접한 연관이 있으며, BOD, SS 그리고 종다양도, 균등도의 생물지수들은 조사지점 대부분에서 유사한 값을 보였으며, 국내 하천에서 소양강 상류 하천 조사 지점의 하천 수질에 대해 전체적으로 빈부수성이며 양호하다는 단편적인 결과를 나타내었다. 따라서 하천수질과 영양 상태에 대한 평가에 사용되는 기존 생물지수 및 하천등급판정기준은 수체 내 영양염류에 민감하여 부영양화 판정에 효과적인 부착조류의 생지화학적 특성을 충분히 활용하지 못하였다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2003년도 추계학술논문발표회 논문집
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• pp.105-126
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• 2003

In Korea most of annual rainfall is concentrated in several episodic heavy rains during the season of summer monsoon and typhoon. Because of uneven rainfall distribution many dams have been constructed in order to secure water supply in dry seasons. The Han River system has the most dams among Korean rivers, and the river is a series of dams now. Reservoirs need different strategy of water quality control from river water. Autochthonous organic matter and phosphorus should be the major target to be controlled in lakes. In this Paper some problems are discussed that makes efforts of water quality improvement ineffective in lakes of Korea, even after the substantial investment to wastewater treatment facilities.1) Phosphorus is the key factor controlling eutrophication of lakes and the reduction ofphosphors should be the major target of water treatment. However, water quality management strategy in Korea is still stream-oriented, and focused on BOD removal from sewage. Phosphorus removal efficiency remains as low as 10-30%, because biological treatment is adopted for both secondary treatment and advanced treatment. The standard for TP concentration of the sewage treatment plant effluent is 6 mgP/l in most of regions, and 2 mg/l in enforced region near metropolitan water intake point. TP in the effluents of sewage treatment plants are usually 1-2 mg/1, and most of plants meet the effluent regulation without a further phosphorus removal process. The generous TP standard for effluents discourages further efforts to improve phosphorus removal efficiency of sewage treatment. Considering that TP standard for the effluent is below 0.1 mg/l in some countries, it should be amended to below 0.1 mg/l in Korea, especially in the watershed of large lakes.2) Urban runoff and combined sewer overflow are not treated, even though their total loading into lakes can be comparable to municipal sewage discharges on dry days. Chemical coagulation and rapid settling might be the solution to urban runoff in regard of intermittent operation on only rainy days.3) Aggregated precipitation in Korea that is concentrated on several episodic heavyrains per year causes a large amount of nonpoint source pollution loading into lakes. It makes the treatment of nonpoint source discharge by methods of other countries of even rain pattern, such as retention pond or artificial wetland, impractical in Korea.4) The application rate of fertilizers in Korea is ten times as high as the average ofOECD countries. The total manure discharge from animal farming is thought to be over the capacity of soil treatment in Korea. Even though large portion of manure is composted for organic fertilizer, a lot of nutrients and organic matter emanates from organic compost. The reduction of application rate and discharge rate of phosphorus from agricultural fields should be encouraged by incentives and regulations.5) There is a lot of vegetable fields with high slopes in the upstream region of the HanRiver. Soil erosion is severe due to high slopes, and fertilizer is discharged in the form of adsorbed phosphorus on clay surface. The reduction of soil erosion in the upland area should be the major preventive policy for eutrophication. Uplands of high slope must be recovered to forest, and eroded gullies should be reformed into grass-buffered natural streams which are wider and resistant to bank erosion.