• 적정기술학회지
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• 제5권1호
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• pp.8-17
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• 2019

Solar pumps, for water lift systems, is becoming popular in rural areas for supplying drinking water in dry seasons when its need is elevated. The development in technology has also made solar pumps readily available and cheap which has increased its demands. So, for scattered settlements having a limited budget for operation and maintenance costs, solar pump is preferred over grid connected electrical pumping systems. This primary objective of the study was to design a solar photovoltaic pumping drinking water supply system for a small health post which is about 45 km east from Kathmandu, the capital city of Nepal. The study also compared and verified the final design with the system's existing design prepared by a development agency. The water source for this study was a confined aquifer 115m below the surface. The water demand was calculated to be 11m³ per day. A 1500 kPa submersible pump attached to a motor was selected and installed. Along with that twelve solar panels, reservoir, transmission main and distribution main was designed. The outcomes conclude solar photovoltaic pumping water supply systems to be cost-effective with an estimated cost of only USD 0.84 million per MLD. Solar pumps require low maintenance and operation costs and its repairs can quickly be done by the local people. The study also shows that solar technology produces no sound, needs no fuel making it environmentally friendly.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.24-24
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• 2020

전세계적으로 지하수 인공함양은 기후변화로 인한 극한가뭄 시대에 효율적인 물확보 방안으로 평가되고 있는 기술로서, 우리나라에서도 2015년 충청 및 강원 지역의 극한 가뭄이 발생한 이후 그 필요성이 증대되고 있다. 지하수 인공함양 대상지역의 평가를 위해서는 물의 수요에 대한 진단, 대상지역의 수리수문학적 특성, 지층의 인공함양 가능성, 원수의 확보 여부, 현행 공급 능력의 진단 등이 복합적으로 이루어져야 한다. 충청남도 홍성군 갈산면 신곡마을은 안정적인 농업용수 공급 시스템이 마련되어 있지 않아 상시 가뭄지역으로서 현행 지하수 관정에 의한 취수능력으로는 주기적인 물 부족이 발생하는 지역이며, 대용량의 암반 지하수 관정 개발도 대수층의 특성상 거의 불가능하다. 따라서, 인공함양의 원수로서 하천수 또는 함양영역 밖의 소용량의 암반 지하수를 고려할 수 있다. 월별 물수지 분석 결과, 농번기 초기인 4월에는 수요량 대비 기존 용수원(관정)에 의한 공급량이 충분하여 99 ㎥/d의 여유가 존재하나, 5월에는 215 ㎥/d의 물부족이 발생하게 된다. 반면에, 하천유출량은 3월 1,297 ㎥/d, 4월 2,899 ㎥/d 등으로서 함양원수로 사용하기에 충분한 수량이 존재할 뿐 아니라, 이 기간의 지하수위가 지표하 약 4~5 m 하부에 위치하고 있어 지하수 함양에 충분한 공간도 확보되는 것으로 평가되었다. 향후 추가적인 정밀한 수치모델링을 통하여 지하수 인공함양을 위한 적정 물량, 지하수위의 분포 변화 예측, 적정 취수량의 결정 등을 수행할 예정이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.59-63
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• 2000

최근 군사기지에서의 환경복원활동은 미국과 독일 등의 일부 선진국을 중심으로 인간의 건강과 환경을 보호하기 위한 차원에서 연구가 진행되고 있다. 본 연구는 상대적 위해성평가 기법을 이용하여 군사기지 복원을 위한 우선순위 결정을 지원함으로서, 효율적인 자원배분이 가능하고 군에 적합한 타당한 모델이 개발될 수 있도록 하는 연구에 초점을 맞추었다. 평가 대상은 군사기지 내에서 유류로 오염된 지역의 전 범위를 대상으로 하였다. 본 연구모델은 유류오염물질 요소, 수용체 요소 및 이동경로 요소의 세가지 평가요소를 평가하여 총 27개의 메트릭스 칸에 각 평가요소의 위해등급을 상호 결합하여 판단함으로서, 종합적인 복원순위를 긴급·보통·유예로 나타냈다. 이는 최대한 간편한 평가체제를 유지하기 위하여 세가지의 등급으로 그룹화하여 평가한 것이다. 본 연구모델은 복원이 요구되는 지역에 대하여 자원의 배분을 위한 접근을 위해 군의 환경관리자는 누구나 쉽게 이해하고 적용 가능하다는 중요한 장점이 있다 따라서, 향후 발전적인 연구과제에서 본 연구모델을 시발점으로 지속적으로 보완된다면, 군의 위해성평가 체계의 정착이 이루어질 것으로 기대한다.

• 한국환경복원기술학회지
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• 제20권5호
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• pp.1-13
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• 2017

Recently, due to worldwide industralization and urbanization, natural environment has been severly damaged and global warning is worsening. Heat wave, torrential rainfall, typhoon and other natural disasters continuously occur due to global warming. Policies such as carbon emission regulation are taken into effect to solve such problems. Such global trend has affected interest to natural ecosystem and developed as a concept of ecosystem-services. This study particularly focused on ground water storage capacity among various ecosystem-services such as climate control and soil formation. It is because Korea suffers from drought and flood every year. Therefore, this study aims to understand objective numerical value of ecosystem-services value regarding ground water storage capacity of biotop classes based on relationship among precipitation, amount of evapotranspiration, and runoff of 7 regions of Chilgok-gun, Gyeongsangbuk-do and to convert the value into economic value. The study calculated ground water storage capacity based on relationship among precipitation, amount of evapotranspiration, and run off. Calculated amount of each capacity was 29.26 million ton($30.2mm/m^2$), 430.46 million ton($140.4mm/m^2$), 11.30 million ton($150.1.0mm/m^2$), 33 milion ton($3.0mm/m^2$). Economical value of ecosystem-service by each biotop classes appeared 4,128,800 thousand KRW ($21.32KRW/m^2$) for agricultural biotop, and 60,403,600 thousand KRW ($98.52KRW/m^2$) for forest biotop, 1,572,800 thousand KRW ($104.4KRW/m^2$) for grassland biotop, and 47,600 thousand KRW ($2.18KRW/m^2$) for bare ground biotop. The result of this study like above, it will be used as important evidentiary material to preserve natural resource effectively from various development business and policies that damages natural eco-system. Also, it is judged that ecosystem-service value by each land coverage will be used as important material for preparing legalistic institution such as establishing natural environment preservation plan, budget for alternative forest resource creation cost.

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권3호
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• pp.1-11
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• 2006

휴 폐금속광산지역 오염방지에 관한 1990년대 중반 이후의 정부 정책과 추진 사업을 법 제도, 기술 개발, 예산의 확보 및 배분에 관하여 분석 평가하였다. 국내의 법 제도는 2005년 제정된 $\ulcorner$광산피해의 방지 및 복구에 관한 법률$\lrcorner$ 로 관련부처별 책임과 역할이 구분되었으며, 토양오염을 포함한 광해방지 및 복구에 관한 국가의 계획과 이를 이행하기 위한 국가의 전담기관, 토양오염을 조사하고 모니터링하는 체계, 그리고 광해방지사업을 시행하기 위한 광해방지사업금을 위한 토대가 마련되었다. 그럼에도 불구하고, 효율적인 휴 폐금속광산지역의 관리 및 복원을 위한 문제점은 상존하고 있다. 이에 관련된 미국, 영국, 네덜란드 등 외국의 법 제도를 비교할 때, 다음과 같은 정책 추진을 제안한다. 첫째, 휴 폐금속광산지역의 오염 책임에 관한 정부와 이 지역의 소유자, 오염자 등의 책임 배분체계 (책임의 배분방법, 광산개발에 의한 토양오염 등의 발생시기에 따른 무과질책임의 적용방법 등) 마련이다. 둘째, 오염에 영향을 받는 인근 지역 주민들의 의사가 존중되고 반영될 수 있도록 지역주민의 참여가 활성화되는 제도적 장치의 마련이다. 셋째, 지역에 관련된 정보들이 체계적으로 일반에게 공개되는 Web-GIS 기반 정보처리체계가 구축되어야 한다. 넷째, 광산지역의 특이성에 바탕을 두어 인체 및 환경 위해성을 고려한 오염지역의 위해성 평가의 마련과 복원이다. 다섯째, 오염원 제거와 오염된 토양 및 광산배수 등 오염지역을 정화하기 위한 적정 예산이 마련되고 배분되어야 한다. 여섯째, 휴 폐금속광산지역의 지역적인 특성을 고려하여 복원을 효율적으로 수행하기 위한 기술이 지속적으로 개발되고, 연구 개발된 새로운 기술이 현장에서 적용되기 위한 인센티브 제도가 마련되어야 한다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.74-84
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• 2017

Soil erosion is often extreme in Korea due to high rainfall intensities and steep slopes, and climate change has also increased the risk of erosion. Despite its significane, erosion-induced soil organic carbon (SOC) emission and water resource loss are not well understood, along with the lack of an integrated surface soil erosion protection policy. Therefore, to design adequate protection policies, land users, scientists, engineers and decision makers need proper information about surface soil and watershed properties related to greenhouse gas emission potential and water conservation capability, respectively. Assuming the total soil erosion of $346Tg\;yr^{-1}$, soil organic matter (SOM) content of 2% (58% of SOM is SOC), and mineralization rate of 20% of the displaced carbon, erosion-induced carbon emission could reach $800Gg\;C\;yr^{-1}$. Also the available water capacity of the soil was estimated to be 15.8 billion tons, which was 14 times higher than the yearly water supply demand in Seoul, Korea. Therefore, in order to prevent of soil erosion, this study proposes a three-stage plan for surface soil erosion prevention: 1) classification of soil erosion risk and scoring of surface soil quality, 2) selection of priority areas for conservation and best management practices (BMP), and 3) application of BMP and post management.

• 한국농공학회지
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• 제45권7호
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• pp.57-69
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• 2003

To evaluate nutrient dynamics with different fertilization in paddy field and develop water quality model, mass balance analysis was performed during growing season of 2001-2002 in field experimental plots irrigated with groundwater. As a result of water balance analysis, most of outflow was surface drainage as about half of total outflow and about 500mm was lost by evapotranspiration. The water budget was well balanced. The runoff from paddy field was influenced by rainfall and forced drain. Especially runoff during early cultural periods more depends on the forced drain. As a result of mass balance analysis, most of nutrient was input by fertilization and lost by plant uptake. Significant amount of nitrogen were supplied by precipitation and input from upper paddy field, comprising 12%∼28% of total inflow. Nutrient loading by surface drainage was occurred showing about 15%∼29% for T-N and 6%∼13% for T-P. The response of rice yield with different fertilization was not significant in this study. Water quality model for paddy field developed using Dirac delta function and continuous source was calibrated and validated to surface water quality monitoring data. It demonstrates good agreement between observed and simulated. The nutrient concentration of surface water at paddy field was significantly influenced by fertilization. During early cultural periods when significant amount of fertilizer was applied, surface drainage from paddy field can cause serious water quality problem. Therefore, reducing surface drainage during fertilization period can reduce nutrient loading from paddy fields. Shallow irrigation, raising the weir height in diked rice fields, and minimizing forced surface drainage are suggested to reduce surface drainage outflow.

• 한국환경과학회지
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• 제23권4호
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• pp.553-560
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• 2014

The rainfall-runoff characteristics in Jeju Island significantly differ from those in inland, due to highly permeable geologic features driven by volcanic island. Streams are usually sustained in the dry conditions and thereby the rainfall-runoff characteristics changes in terms of initiating stream discharge and its types, depending highly on the antecedent precipitation. Among various the rainfall-runoff characteristics, lag time mainly used for flood warning system in river and direct runoff ratio for determining water budget to estimate groundwater recharge quantity are practically crucial. They are expected to vary accordingly with the given antecedent precipitation. This study assessed the lag time in the measured hydrograph and direct runoff ratio, which are especially in the upstream watershed having the outlet as $2^{nd}$ Dongsan bridge of Han stream, Jeju, based upon several typhoon events such as Khanun, Bolaven, Tembin, Sanba as well as a specific heavy rainfall event in August 23, 2012. As results, considering that the lag time changed a bit over the rainfall events, the averaged lag time without antecedent precipitation was around 1.5 hour, but it became increased with antecedent precipitation. Though the direct run-off ratio showed similar percentages (i.e., 23%)without antecedent precipitation, it was substantially increased up to around 45% when antecedent precipitation existed. In addition, the direct run-off ration without antecedent precipitation was also very high (43.8%), especially when there was extremely heavy rainfall event in the more than five hundreds return period such as typhoon Sanba.

• 한국물환경학회지
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• 제34권6호
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• pp.678-687
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• 2018

The purpose of this study was to understand the unique and complicated feature of urban stream receiving various inflows. The Yangjae stream, the second tier of the Han River, runs through the southern parts of Seoul, Korea and its middle part flows on the boundary of Seoul where land use is actively changing. Stream flow was greatly influenced by rainfall. Other than rainfall events, effluent discharge from wastewater treatment plant (WWTP) comprised 51 % of stream flux. As a result, majority ions water chemistry was changed at the receiving zone of the discharged effluent (Zone A). Its contribution increased to 69.9 % at the second sampling period with low stream flow. In the middle zone, inflows from the northern area, recently developed to a residential district showed low $NO_3-N$ and high $HCO_3$, Ca, $SO_4$, and $SiO_2$ indicating the effects of groundwater and concrete. One inflow (T-8), with extremely high Na and Cl, median $SiO_2$, was assessed to have anthropogenic influence, however its contribution to main stream was under 1 %. Road construction near Y-13 also affected water chemistry leading to the highest Na and Cl concentration. These hydro chemical changes can be critically used to evaluate the changes in water budget and fate of chemicals in a peri-urban watershed occasioned by human activities on the Yangjae.