• 대한안전경영과학회지
• /
• 제16권4호
• /
• pp.441-449
• /
• 2014

As people seek a healthy, wealthy, and quality life more than before, interests in mineral water are picking up and the consumption continues to increase accordingly. In an experiment to examine changes in the water quality after mineral water on the market was kept indoor and outdoor for four weeks, there seemed to be no problem in external appearance. Water kept in an outdoor storage contained more odor-savor than water kept in an indoor storage. Odor was not detected in 90% of the sample, and savor not in 80% of it. As for the mechanism of odor-savor generation, the elution of chemical substances from a container may be taken into consideration. In general, odor and savor have turned out to be in close correlation to each other. The average number of bacteria in the sample mineral water was $200{\pm}10CFU/mL$, and such factors as area of storage and ozone post-treatment did not cause significant effects on the reproduction of common microbes. Hence, it is thought that strict regulations on a production process and reduction of the period of circulation will contribute to customers consumption rates.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2002년도 학술발표회 발표논문집
• /
• pp.369-372
• /
• 2002

To provide the basic information for the water quality improvement of the Sumjin River Basin, the water qualities of the Chooryeong-chon watershed were investigated from May in 1999 to September in 2002.

• Membrane and Water Treatment
• /
• 제10권1호
• /
• pp.1-11
• /
• 2019

The Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) predicted that recent extreme hydrological events would affect water quality and aggravate various forms of water pollution. To analyze changes in water quality due to future climate change, input data (precipitation, average temperature, relative humidity, average wind speed and sunlight) were established using the Representative Concentration Pathways (RCP) 8.5 climate change scenario suggested by the AR5 and calculated the future runoff for each target period (Reference:1989-2015; I: 2016-2040; II: 2041-2070; and III: 2071-2099) using the semi-distributed land use-based runoff processes (SLURP) model. Meteorological factors that affect water quality (precipitation, temperature and runoff) were inputted into the multiple linear regression analysis (MLRA) and artificial neural network (ANN) models to analyze water quality data, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), total nitrogen (T-N) and total phosphorus (T-P). Future water quality prediction of the Anseongcheon River basin shows that DO at Gongdo station in the river will drop by 35% in autumn by the end of the $21^{st}$ century and that BOD, COD and SS will increase by 36%, 20% and 42%, respectively. Analysis revealed that the oxygen demand at Dongyeongyo station will decrease by 17% in summer and BOD, COD and SS will increase by 30%, 12% and 17%, respectively. This study suggests that there is a need to continuously monitor the water quality of the Anseongcheon River basin for long-term management. A more reliable prediction of future water quality will be achieved if various social scenarios and climate data are taken into consideration.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2001년도 학술발표회 발표논문집
• /
• pp.21-24
• /
• 2001

As one of the phil-environmental alternative plan of Saemankeum project, gradual development is recommended. The procedure of the Saemankeum project start with the completion of 32 km long sea-dikes which contains two discharge gates until the year 2004. Second step is pre-development of Mangyoung area permitting temporary intrusion of sea water, i.e. tides, by the opening of discharge gate until the environmental evaluation on the water quality of this area secures permanent meet to government's water quality standard. Therefore this study is to predict the future condition of this tidal flat with the point of view tidal environments, salt, water quality, soil mechanics, etc. of Mangyoung area when the sea water still passed in the inland reservoir through the discharge gate.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2017년도 학술발표회
• /
• pp.545-545
• /
• 2017

본 연구에서는 낙동강 유역 본류와 주요 지천의 오염총량관리대상지점을 대상으로 수질 현황과 시공간적 수질특성을 분석을 위해 하수처리장과 주요 지천의 유입으로 인한 낙동강 본류 수질의 공간적 변화양상과 계절별 하천유량의 변화에 따른 수질특성을 분석하였다. 자료구축을 위해 국가수자원관리종합정보시스템(WAMIS)의 하천 공간 지형 자료, 국립환경과학원의 수질관측지점 공간지형자료, 그리고 전국오염원조사 자료의 하수처리장 공간 지형 자료를 이용하였다. 수질자료는 국립환경과학원 물환경정보시스템에서 제공하는 8일 간격 수질자료를 2004년부터 2015년까지 수집하여 이용하였고, 수집한 자료는 갈수기와 전체 기간에 대해 수질 항목(유량, BOD, T-N, T-P)별로 산술 평균하였다. 하수처리장 32개소의 방류수질 자료는 국립환경과학원의 전국오염원조사 자료를 2012년부터 2015년까지 수집하여 갈수기인 봄, 가을철에 대해 수질항목 별로 산술평균하였다.

• 한국환경과학회지
• /
• 제28권3호
• /
• pp.357-369
• /
• 2019

In this study, the water quality components (pH, BOD, COD, TOC, SS, DO, TP) and the water quality, observed for 10 years (2008~2017) in the five tributaries of the Nakdong River with the highest flow rates, were analyzed. Monthly levels of the water quality components were estimated and regression functions were used to quantitatively explain the changes in the BOD and COD components, with respect to the TOC components. The results of analyzing the water quality levels in terms of the living environmental standards show that the lowest water quality was observed midstream (ST-3) and the highest water quality was observed upstream (ST-1 and ST-2). The regression function was estimated to be a linear function in all five tributaries, and the goodness of fit of the function was high upstream (ST-2), midstream (ST-3), and downstream (ST-4). According to the regression analysis using the observation data from 2008~2017, we found that the consumption of dissolved oxygen increased with an increase in organic matter in the major tributaries of the Nakdong River.

• 한국물환경학회지
• /
• 제22권4호
• /
• pp.666-671
• /
• 2006

Effects of a rainfall event (July 28, 2005) on the hydrochemical characteristics of the Jungrang river, the biggest tributary of the Han river, was investigated. Significant spatial variations in the hydrochemical characteristics were observed. At JR2 location, concentrations of T-N and T-P were relatively low indicating occurrence of active oxidation in the stepped drop structure. At JR3 location, concentrations of Na, K, Cl, $NH_4-N$ and EC were elevated suggesting increased discharge from the nearby waste-water treatment plant and tributaries. The rain event diluted major dissolved ion concentrations in the river by 12~52%. The $NO_3-N$ levels were preserved during the rain then increased about twofold after rainfall, suggesting increased discharge of nitrate-contaminated groundwater. Heavy metals including Cd, Co, Cr, Cu and Pb were not detected in all water samples and the leachates from surface sediment samples. Concentrations of Fe, Mn, Al and Zn were below the Korean Drinking Water Guideline. Results of this study suggested that establishment of water-quality monitoring protocols describing temporal and spatial variations in parameters sensitive to rainfall events, relatively steady factors, and contaminant sources is required.

• 한국물환경학회지
• /
• 제27권2호
• /
• pp.159-166
• /
• 2011

The use of land cover was sharply changed during 1975~2007 in the Kyungan watershed $(561.12 km^2)$. The changes occurred over an area of more than $227.65 km^2$ during the overall period at changing rates of 1.04% per year for water area, 1.79% per year for residential area, 2.99% per year for bare area, 3.03% per year for wetland area, 3.04% per year for grass area, 0.87% per year for forest and 2.32% per year for agriculture area. Water, residential, bare and wetland areas increased, while grass, forest and agriculture areas decreased during the last 32 years. BOD concentrations of representative sites for each sub-watershed continuously increased until the early 2000s as residential area increased with the highest discharged load, but decreased after the mid 2000s except upper Kyungan watershed. Such decline appears to be associated with the planning of Total Maximum Daily Load management for Gwangju city and expansion of waste water treatment plant. It is necessary to control land use/cover changes of the upper watershed and to prepare appropriate watershed management system for improvement in river environment including water quality, stream flow and bio-diversity.

• 자원ㆍ환경경제연구
• /
• 제10권3호
• /
• pp.387-412
• /
• 2001

This paper is to empirically test scope effects proposed to judge the internal consistency of contingent valuation method. The application was illustrated for the case of estimating people's WTP for improving water quality at Man Kyoung River in the Chon Buk area. The CV survey was carefully designed and implemented by carrying out recommendations from the NOAA Blue Ribbon panel. Using a split sample, we conducted the Cochran-Mantel-Haenszel test with the frequency distribution of no responses, calculated the Turnbull low bound mean for WTP, and measured the mean WTP from estimated variation functions. The test results consistently exhibited that the CV estimates of WTP were adequately responsive to the size of water quality changes being offered. The mean WTP for improving water quality suitable for swimming (5,171 and 5,212 won) was significantly larger than that for agricultural use and fishing activity (3,280 and 3,136 won).

• 한국환경과학회지
• /
• 제27권10호
• /
• pp.883-899
• /
• 2018

In this study, water quality data of eight main sites in the Geumho River watershed were collected and analyzed for long-term changes in water quality over the period from 2005 to 2015. The results showed that BOD concentration was gradually improved by the Total Maximum Daily Load (TMDL), stages 1 and 2. Recently, a tendency of increasing BOD concentration was observed in the downstream section of the river. The concentration of COD was analyzed to be contaminated throughout the water system regardless of the water quality improvement project, and the TN concentration tended to increase in the midstream of the river from 2013. The TP concentration has clearly decreased from 2012 after the second stage of TMDL. For the statistical analysis of PCA ordination, monthly water qualities (pH, DO, Electrical Conductivity (EC), Water Temperature (WT), BOD, COD, TN, TP, TOC, and SS) and flow rate data for 5 years from 2012 to 2016 were used. Seasonally the Geumho River showed an increase in the TN concentration at point sources during the dry season (December to February). TP showed the effect of non-point sources in the summer, because rainfall has caused a rise in flow rate in the upstream. Besides, the origin of pollution source was changed from non-point sources with BOD, COD, and TOC.