• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.154-154
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• 2016

우리나라는 급격한 경제 발전과 함께 빠르게 도시화가 진행되었다. 하지만 도시화가 진행됨에 따라 불투수면적의 증가로 인해 도시지역 침수에 대한 위험이 야기되고 있다. 배수관망 체계는 지역 내의 강우를 빠르게 배출하는데 목적을 두고 발전해 왔다. 이러한 노력에도 불구하고 서울시는 2010년, 2011년과 같이 반복적인 침수로 인명과 재산 피해를 겪고 있는 실정이다. 본 연구에서는 2010년과 2011년을 기준으로 침수된 서울시 100개의 유역을 선정하고 깁스모형을 적용하여 침수지역을 중심으로 한 배수관망체계의 특성을 분석하였다. 이와 함께 각 유역의 IA(Impervious Area)와 DCIA(Directly Connected Impervious Area)를 근거로 불투수면적의 공간적 분포 특성도 분석하였다. 깁스모형을 이용한 네트워크 특성과 불투수면적의 공간적 분포 특성을 근거로 침수지역과의 상관관계를 분석하였다. 이를 바탕으로 도시 지역의 배수관망의 효율성을 판단하고 지역 특성에 최적화된 배수관망체계를 구축하는데 도움이 될 것이라 기대된다.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.10
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• pp.739-747
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• 2011

The major 81 tributaries in Chungcheongnam-do were monitored for flowrate and water quality in order to understand the characteristics of the watershed and to select the tributary catchment for improving water quality. The value of flowrate in the tributaries at Nonsancheon catchment at the Geum-River watershed and Gokgyocheon, Muhancheon, Sapgyocheon at the Sapgyo-Reservoir watershed, which is located in the southern and northern area in Chungcheongnam-do, was relatively greater than the other watersheds. The concentration of water pollutants regardless of water quality parameters in Nonsancheon catchment at the Geum-River watershed, Gokgyocheon catchment at the Sapgyo-Reservoir watershed and the Anseongcheon watershed, which have a dense source of pollution, were higher than the other watersheds. However, 64 percent of the tributaries at the Geum-River watershed, 45 percent of tributaries at the Sapgyo-Reservoir watershed, 26 percent of tributaries at the Geum-River watershed all satisfied the Class II regulations in the Framework Act on Environment Policy, but all of the tributaries located in the Anseongcheon watershed exceeded the Class II regulations. Therefore, the policy for improving the water quality of the tributary in Chungcheongnam-do should be established in the following order: Anseongcheon, Seohae, Sapgyo-Reservoir watersheds. Consequently, the tributary catchment for improving water quality, which has a large flowrate and a high concentration of water pollutants, was selected at Ganggyeongcheon, Geumcheon, Nonsancheon, Seokseongcheon, Seungcheoncheon, Jeongancheon, Jeungsancheon (so far Geum-River watershed), Gokgyocheon, Namwoncheon, Maegokcheon, Muhancheon, Sapgyocheon Oncheoncheon, Cheonancheon (so far Sapgyo-Reservoir watershed), Gwangcheoncheon, Dangjincheon, Daecheoncheon, Dodangcheon, Waryongcheon, Cheongjicheon, Pangyocheon, Heungincheon (so far Seohae watershed), Dunpocheon, Seonghwancheon, Ipjangcheon (so far Anseongcheon watershed). The plans as installation of environmental facilities to reduce the source of pollution for improving the water quality of these tributary catchments should be urgently established and implemented.

• The Korean Journal of Ecology
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• v.18 no.3
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• pp.341-351
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• 1995

The relationship between land uses and water quality was investigated at Kyong-an Stream. Some 70% of this watershed was forested area, half of which was comprised of Pinus densilflora community. Concentrations of $NH_4^{+},\;NO_3^{-},\;NO_2^{-}, total nitrogen, $Cl^{-},\;PO_4^{3-}$, DO, and BOD increased gradually from upstream to downstream, whereas heavy metals did not have such tendancy with the exception of a few sites. Urban area was significantly correlated with hardness and chloride concentration. Relationship among phosphate concentration(P), cultivated field area(F), and stream length(S) in each basin was P = 1.7912 F/S＋0.0103. the concentration of $NH_4^{＋}$ was positively correlated with the population size and cow density within the catchment. The effect of urban area(U) and stream length of the pH(pH) was represented by pH = -4.7344 U/S＋6.52. It can be concluded that the control of nonpoint source pollution as well as point source pollution is one of the important problems of water quality management, especially geological properties must be considered for sustainable development.

• Journal of the Korean Institute of Rural Architecture
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• v.15 no.1
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• pp.71-78
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• 2013

According to the rapid change in the era of Korea, there have been significant changes in the buildings and facilities in the rural area of the country, and thus in the landscape of the agricultural and fishing villages due to the painting of colors that are not in harmony with the surrounding natural environment. Recently, the value recognition on the rural landscape has greatly changed and studies are actively performed on rural colors. To keep up with this trend this study is intended to propose coloring plan of Byutgari and Eumpo area for their entire landscape including the facilities to harmonize with their natural and cultural characteristics and surrounding environments. This plan was related to the establishment of the landscape planning of the region in Taean-gun, Chungcheongnam-do, based on the already prepared rural environmental coloring guideline. This study has its significance in that it provided a coloring process that can be applied to the targeted are as well as other area, continuing the context of the precedent studies. It is greatly expected that the regional characteristics will be strengthened owing to the establishment of coloring guidelines.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.349-357
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• 2006

Nowadays, the discharges of urban streams during dry season are depleted because the hydrologic cycle in the watershed has been destroyed due to the expansion of the impermeable area, the excessive groundwater pumping, climate change, and so forth. The streamflow depletion may bring out severe water quality problems. This research are to investigate the hydrologic characteristics and to develop a technology to restore sound hydrologic cycle of Anyangcheon watershed. For the hydrological cycle analysis of the Anyangcheon watershed, continuous simulations of urban runoff were performed for the upstream basin of Gocheok bridge whose basin area covered 4/5 of the whole catchment area. The increase of impervious area by urbanization was analysed and its effect on urban runoff was evaluated. The SWMM 5 (Storm Water Management Model 5) was used for the continuous simulation of urban runoff. The analysis results of urbanization effect on runoff are as follows: the surface runoff in 2000 increases to 65% of the whole precipitation whereas the surface runoff in 1975 amounts to 50% of the precipitation; the groundwater runoff in 2000 amounts to 7% and shows 6% decrease during the period from 1975 to 2000.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.112-128
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• 2014

This study aims to analyse the variation of spatial accessibility pattern based on 2SFCA(2 Step Floating Catchment Area) by changing its parameter values. The general pattern of the result of 2SFCA analysis shows that the spatial accessibility value is decreased by growing base population, while the spatial accessibility value is increased by growing PPR(Provider to Population Ratio). The three characteristics of local pattern in the Gumi City are founded by cluster analysis on the sensitive analysis procedure. Firstly, the variation of the accessibility values is insignificant in the fringe area of the Gumi City. Secondly, the variation of the accessibility values is diverse in the surrounding area of the welfare facilities. Especially, Dong areas are more sensitive to PPR variation, while others are more sensitive to base population variation. Thirdly, the larger parameter values, the more the spatial accessibility of the central areas, where elder people can access welfare facilities more easily, is improved. It needs to choose parameter values with caution to analyse spatial accessibility based on 2SFCA.

• Ecology and Resilient Infrastructure
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• v.3 no.2
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• pp.100-109
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• 2016

Low impact development (LID) facilities are established for the purpose of restoring the natural hydrologic cycle as well as the removal of pollutants from stormwater runoff. Improved efficiency of LID facilities can be obtained through the optimized interaction of their major components (i.e., plant, soil, filter media, microorganisms, etc.). Therefore, this study was performed to evaluate the performances of LID facilities in terms of runoff and pollutant reduction and also to provide an optimal maintenance method. The monitoring was conducted on four LID technologies (e.g., bioretention, small wetlands, rain garden and tree box filter). The optimal SA/CA (facility surface area / catchment area) ratio for runoff reduction greater than 40% is determined to be 1 - 5%. Since runoff reduction affects the pollutant removal efficiency in LID facilities, SA/CA ratio is derived as an important factor in designing LID facilities. The LID facilities that are found to be effective in reducing stormwater runoff are in the following order: rain garden > tree box filter > bioretention> small wetland. Meanwhile, in terms of removal of particulate matter (TSS), the effectiveness of the facilities are in the following order: rain garden > tree box filter > small wetland > bioretention; rain gardens > tree box filter > bioretention > small wetland were determined for the removal of organic matter (COD, TOC), nutrients (TN, TP) and heavy metals (Cu, Pb, Cd, Zn). These results can be used as an important material for the design of LID facilities in runoff volume and pollutant reduction.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.455-468
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• 1999

Carbonated mineral waters fo $Ca(Mg)-HCO_3$ type spring out fissure of Jurassic granite in the valley floor of the Chungsong area. The water has been long as a Dalki medicinal water because of its unique therapeutic effect against clacium deficit, stomach and skin troubles, ect. The water has a high $CO_2$ concentration ($P_{CO_2}$=0.51~1.12atm) and exhibits strong pH buffering (5.9~6.26) by $H_2CO_3/HCO_3$ couple. Electrical conductivity ranges from 1,900 to 3100 $\mu$S/cm. Environmental isotopic data $(^{2}H/^{1}H, ^{18}O/^{16}O \;and \;^3H)$ indicates that the water is of meteoric origin recharged in the Cretaceous sedimetary strata distributed in upper part of the catchment area at least before 1950s, The high $P_{co_2}$ and carbon isotope data (${\delta}^{13}C=-3\sim-0.2\textperthousand$) suggest that the potential source of carbonated mineral water was originated in deep-seated $CO_2$ as wel as aboundant carbonate minerals of sedimentary desimetary rocks. The major source minerals of the dissoved species in the carbonated mineral water appear to be carbonate minerals, albite and K-feld-spar in sedimentrary rocks.

• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.622-631
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• 2014

The purpose of this research was to find a proper disposal rainfall extent to improve water quality. SWMM was applied to select catchment area and tested first flush load and rainfall extent. BOD 40mg/L was selected to dispose the first flush and sewer overflow with the same as the criteria of Sewerage Act. Design rainfall, BOD load ratio of first flush sewer overflow, and the ratio of disposal flow were analyzed under various rainfall distribution. BOD load and design rainfall to treat overflow in situation of first flush extent with 4.3~17.4% were 56~87% and 3.8~6.8 mm/day, respectively. In urban area, first flush loads were not correspond to land activities, but tend to increase with increasing rainfall amount and drainage area. The more the distribution of rainfall is similar to Huff-frontal or central distribution of rainfall, the more increase the first flush loads.

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.1-15
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• 1993

This research aims to investigate some respects of chemical weathering processes, espcially the amount of solute leaching, formation of clay minerals, and the chemical weathering rate of granite rocks under present climatic conditions. For this purpose, I investigated geochemical mass balance in a small catchment and the mineralogical composition of weathered bedrocks including clay mineral assemblages at four res-pective sites along one slope. The geochemical mass blance for major elements of rock forming minerals was calculated from precipitation and streamwater data which are measured every week for one year. The study area is a climatically and litholo-gically homogeneous small catchment($3.62Km^2$)in Anyang-shi, Kyounggi-do, Korea. The be-drock of this area id Anyang Granite which is composed of coarse-giained, pink-colored miner-als. Main rock forming minerals are quartz, K-Feldspar, albite, and muscovite. One of the chracteristics of this granite rock is that its amount of Ca and Mg is much lower than other granite rock. The leaching pattern in the weathering profiles is in close reltion to the geochemical mass balance. Therefore the removal or accumulation of dissolved materials shows weathering patterns of granite in the Korean peninsula. Oversupplied ions into the drainage basin were $H^+$, $K^+$, Fe, and Mn, whereas $Na^2+$, $Mg^2+$, $Ca^2+$, Si, Al and $HCO-3^{-}$ were removed from the basin by the stream. The consumption of hydrogen ion in the catchment implies the hydrolysis of minerals. The surplus of $K^+$ reflects that vegetation is in the aggravation stage, and the nutrient cycle of the forest in study area did not reach a stable state. And it can be also presumed that the accumulation of $K^+$ in the top soil is related to the surplus of $K^+$. Oversupplied Fe and Mn were presumed to accumulate in soil by forming metallic oxide and hydroxide. In the opposite, the removal of $Na^+$, Si, Al resulted from the chemical weathering of albite and biotite, and the amount of removal of $Na^+$, Si, Al reflected the weathering rate of the bedrock. But $Ca^2+$ and $Mg^2+$ in stream water were contaminated by the scattered calcareous structures over the surface. Kaolinite is a stable clay mineral under the present environment by the thermodynamical analysis of the hydrogeochemical data and Tardy's Re value. But this result was quite different from the real assemblage of clay miner-als in soil and weathered bedrock. This differ-ence can be explained by the microenvironment in the weathering profile and the seasonal variation of climatic factors. There are different clay forming environments in the stydy area and these differences originate from the seasonal variation of climate, especially the flushing rate in the weathering profile. As it can be known from the results of the analysis of thermodynamic stability and characteristics of geochemical mas balance, the climate during winter and fall, when it is characterized by the low flushing rate and high solute influx, shows the environmental characteristics to from 2:1 clay minerals, such as illite, smectite, vermiculite and mixed layer clay minerals which are formed by neoformation or transformation from the primary or secondary minerals. During the summer and spring periods, kaoli-nite is a stable forming mineral. However it should consider that the other clay minerals can transformed into kaolinite or other clay minerals, because these periods have a high flushing rte and temperature. Materials which are directly regulated by chemical weathering in the weathered bedrock are $Na^+$, Si, and Al. The leaching of Al is, however, highly restricted and used to form a clay mineral, and that of Si falls under the same category. $Na^+$ is not taked up by growing veget ation, and fixed in the weathering profile by forming secondary minerals. Therefore the budget of $Na^+$ is a good indicator for the chemical weathering rate in the study area. The amount of chemical weathering of granite rocks was about 31.31g/$m^2+$/year based on $Na^+$ estimation.