• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1994.05a
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• pp.51-53
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• 1994

담수는 인간의 생존에 필수적인 요소이다. 우리는 매일 일정량의 물을 섭취하고 있으며, 일상에서 직접, 간접적으로 물과 관련되지 않고서는 생활할 수 없다. 지구 표면의 약 70%가 물로서 덮여 있다고는 하지만 인간의 생활에 직접적인 이용가치가 있는 담수(지표수)는 전체 물의 용적의 2%에 지나지 않는다. 한국의 연평균 강수량은 1,274mm로서 세계 연평균 강수량인 970mm보다 많은 편이나 인구 1인당 연간 강수량은 약 3,000m3으로서 세계 평균인 34,000m3의 11분의 1에 지나지 않는다. 수자원총량중 지하침투와 증발에 의해 손실되는 양을 제외한 하천유출량은 전체의 55%인 697억m3으로서 이것이 곧 가용수자원량이다. 그러나 하절기 강우집중도가 높은 우리나라 실정에서는 가용수자뭔량중 수자원총량의 37%가 홍수시 유출되고 실제 이용량은 수자원총량의 18%인 230억m3에 불과하여 인구증가와 함께 수자원의 가치가 더욱 증대하고 있는 실정이다. 더우기 지하수 이용량은 19억m3에 불과함에 따라 우리나라는 실제 이응수자 원량의 90% 이상을 지표수에 의존하고 있으며, 그 중 약 40%가 호소수로 구성되어 있다. 이러한 수자원 이용효율의 취약성으로 인해 제한된 수자원 용량과 생활 및 농공용수의 과수요에 따른 불균형으로 근래 많은 하천이 갈수기나 평수기시 친천화되어 가고 있어 수중생태계에 큰 위협을 주고 있다. 또한 이에 더하여 산업발달과 함께 수질오염원은 양적으로는 물론 질적으로도 증가일로에 있어 기존의 유기 및 중금속 오염물질을 포함해 수많은 신생 유기화합물질이 수계에 유출되고 있으며, 이에 더해 질소 및 인으로 대표되는 영양물질의 유입과다로 국내 대다수의 호수가 부영양화의 새로운 위협에 직 면해 있다. 우리나라에는 적은 유입유량에 큰 저수용량 및 긴 체류시간으로 대표되는 대규모 자연호는 없으며, 대부분이 매단위 강을 막아 형성된 체류시간 1년 이하의 인공호로서 그 중 안동호, 충주호, 대청호 등은 비교적 체류시간이 긴 호소형 인공호로, 팔당호나 기타 대부분의 호수는 체류시간이 짧은 하천형 인공호로 대별된다(Table 1). 이처럼 국내 호소는 국외의 자연 호와는 다른 구조적 특성을 가짐에 따라 부영양화 특성 역시 매우 상이하고, 호소형 인공호와 하천형 인공호간의 차이 역시 현저하여 일률적인 관리대책을 설정하기가 어려운 실정에 있다. 또한 각 호수의 유역특성이 상이함에 따라 호수별로 유역 오염원의 오염부하율이 현저히 달라(Table 2) 호수에 따른 특성적인 유역관리(Lake-specific management)가 요구되고 있다 정상상태(Steady state)가 아닌 국내 호소에 대해 국외 자연호의 인단순모델 (Simple phosphorus budget model)을 그대로 적용하는 것에 다소 무리한 점이 따르나, 평균적인 개념으로 OECD의 유역부하량 및 호소특성에 따른 부영양화 판정모델을 적용한다면, 국내 주요 호수는 모두 부영양 수준에 있다. 또 각 호수별로 부영양화 제어를 위해 요구되는 인의 삭감부하량은 상당량이 되어 현실적으로 관리가 이미 어려운 실정에 와 있다. 호수의 부영양화는 조류 발생으로 이어지며, 그에 따른 폐해는 각종 형태로 나타나는데 대표적으로 이취미 발생이나 유해조류에 의한 독성물질의 배출, 정수처리 과정의 THM 발생등이 주로 문제가 되고 있다. 따라서 국내 호수의 구조적 특성별 부영양화 실태를 파악하고 그에 따른 영향 및 관리방안에 관한 종합적 고찰이 차후 수질관리를 위해 요구되고 있으며, 특히 납조류로 대표되는 유해조류의 독성영향에 관한 연구는 시급한 실정에 있다.

• Journal of Animal Environmental Science
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• v.18 no.1
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• pp.19-24
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• 2012

The first objective of this study is to estimate emission coefficient of organic carbon regarding its inflow and discharge for dairy farm through reviewing domestic and foreign literature published or reported previously. Its second objective is to provide fundamental data to establish carbon cycle system related to livestock production. Based on literature review, emission coefficients by inflow of organic carbon into dairy farm were 5.9 ton C/head/year for feedstuff ingestion by milk cow, 2.3 ton C/head/year for recycling manure compost of milk cow to grassland, 318 g C/$m^2$/year for contents in grassland, 145 g C/$m^2$/year for contents in fodder crop, and 17 g C/$m^2$/year for $CO_2$ uptake by fodder crop, respectively. on the other hand, emission coefficients by discharge of organic carbon from dairy farm were 2,9 ton C/head/year for emission of $CO_2$ and $CH_4$ by respiration and burp of milk cow, 0.4 ton C/head/year for emission of $CO_2$ and $CH_4$ by decomposition of organic carbon in manure of milk cow, 440 g C/$m^2$/year for emission of $CO_2$ from grassland, and 0 for elution of organic carbon in grassland into underground water, respectively.

• Proceedings of the KSEEG Conference
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• 2001.05b
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• pp.42-63
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• 2001

The detail survey on the Songsanri tomb site including the Muryong royal tomb was carried out during the period from May 1 , 1996 to April 30, 1997. A quantitative analysis was tried to find changes of tomb itself since the excavation. Main subjects of the survey are to find out the cause of infiltration of rain water and groundwater into the tomb and the tomb site, monitoring of the movement of tomb structure and safety, removal method of the algae inside the tomb, and air controlling system to solve high humidity condition and dew inside the tomb. For these purposes, detail survery inside and outside the tombs using a electronic distance meter and small airplane, monitoring of temperature and humidity, geophysical exploration including electrical resistivity, geomagnetic, gravity and georadar methods, drilling, measurement of physical and chemical properties of drill core and measurement of groundwater permeability were conducted. We found that the center of the subsurface tomb and the center of soil mound on ground are different 4.5 meter and 5 meter for the 5th tomb and 7th tomb, respectively. The fact has caused unequal stress on the tomb structure. In the 7th tomb (the Muryong royal tomb), 435 bricks were broken out of 6025 bricks in 1972, but 1072 bricks are broken in 1996. The break rate has been increased about 250% for just 24 years. The break rate increased about 290% in the 6th tomb. The situation in 1996 is the result for just 24 years while the situation in 1972 was the result for about 1450 years. Status of breaking of bircks represents that a severe problem is undergoing. The eastern wall of the Muryong royal tomb is moving toward inside the tomb with the rate of 2.95 mm/myr in rainy season and 1.52 mm/myr in dry season. The frontal wall shows biggest movement in the 7th tomb having a rate of 2.05 mm/myr toward the passage way. The 6th tomb shows biggest movement among the three tombs having the rate of 7.44mm/myr and 3.61mm/myr toward east for the high break rate of bricks in the 6th tomb. Georadar section of the shallow soil layer represents several faults in the top soil layer of the 5th tomb and 7th tomb. Raninwater flew through faults tnto the tomb and nearby ground and high water content in nearby ground resulted in low resistance and high humidity inside tombs. High humidity inside tomb made a good condition for algae living with high temperature and moderate light source. The 6th tomb is most severe situation and the 7th tomb is the second in terms of algae living. Artificial change of the tomb environment since the excavation, infiltration of rain water and groundwater into the tombsite and bad drainage system had resulted in dangerous status for the tomb structure. Main cause for many problems including breaking of bricks, movement of tomb walls and algae living is infiltration of rainwater and groundwater into the tomb site. Therefore, protection of the tomb site from high water content should be carried out at first. Waterproofing method includes a cover system over the tomvsith using geotextile, clay layer and geomembrane and a deep trench which is 2 meter down to the base of the 5th tomb at the north of the tomv site. Decrease and balancing of soil weight above the tomb are also needed for the sfety of tomb structures. For the algae living inside tombs, we recommend to spray K101 which developed in this study on the surface of wall and then, exposure to ultraviolet light sources for 24 hours. Air controlling system should be changed to a constant temperature and humidity system for the 6th tomb and the 7th tomb. It seems to much better to place the system at frontal room and to ciculate cold air inside tombs to solve dew problem. Above mentioned preservation methods are suggested to give least changes to tomb site and to solve the most fundmental problems. Repairing should be planned in order and some special cares are needed for the safety of tombs in reparing work. Finally, a monitoring system measuring tilting of tomb walls, water content, groundwater level, temperature and humidity is required to monitor and to evaluate the repairing work.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.4
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• pp.361-369
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• 2008

Control of ground water is one of the most important factors for long-term operation of tunnel because most of tunnel is located in the ground. In case of leakage tunnel, there is no pore water pressure on the lining when the drainage system is properly working. After long-term operation, however, the pore water pressure can be developed on the lining due to the deterioration of the drainage system. The increased pore water pressure on the lining is termed here as 'residual pore water pressure'. Residual pore water pressure can be measured by piezometer, but it is generally not allowed because of damages of drainage system. Therefore, an indirect and nondestructive method is required for evaluating the residual pore water pressure. Moreover, understanding of pore water pressure is needed during healthy operation of the lining. In this study, a new method for evaluation of pore water pressure on the lining during operation is proposed using theoretical and numerical analysis. It is shown that the method is particularly useful for stability investigation of pore water pressure on the lining during operation using theoretical analysis with normalized pore water pressure curve.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.27-33
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• 2012

The purpose of this study is to evaluate the field applicability of Quantum Stick in scale deposit prevention for subway tunnels in Seoul. This technology was installed into drainpipes and its performance was monitored through occasional site visits. SEM and EDS were also performed on scale collected from these drain pipes. Results showed a decrease in scale deposits due to Quantum Stick treatment. In the field test, the device was found to be effective in preventing scale formation in new pipes as well as reducing existing scale in previously installed pipes. However, further investigations are necessary to account for various environmental conditions. In conclusion, the results indicate that molecular Vibration technology is effective in suppressing scale formation.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.45-55
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• 2004

The paper describes the rainfall-runoff. soil moisture distribution and subsurface flow of 'U-shaped Goll' valley head slope to evaluate quantitatively the interaction between the water circulation system and geomorphic development. The findings are as follows: The fissure and the pipe entrance in front of 'U-shaped Goll' introduce a lot of direct runoff into either the soil pipe or the soil layer to accelerate the erosion of the soil layer, so that they are likely to contribute to the expansion and development of the soil pipe. Most of soil water is to be drained in pipe flow, while some of remaining soil water is to be fed into groundwater. Therefore, low rainfall intensity is thought to let both the groundwater level and the pipe flow react sensitively by the effects of the precedent rainfall even at events: As a result, the soil pipe is said to be an important factor having influence upon the material balance of 'U-shaped Goll' valley head slope. On the other hand, the groundwater shows greater specific flux at the top than at the bottom, and relatively larger specific flux is applied to the top to make 'U-shaped Goll' valley head slope go back to the top.

• Journal of the Korean Geotechnical Society
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• v.21 no.3
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• pp.87-98
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• 2005

When a tunnel is excavated below groundwater table, the groundwater flows into the excavated wall of tunnel and seepage forces are acting on the tunnel wall. The ground reaction curve is defined as the relationship between internal pressure and radial displacement of tunnel wall. Therefore, the ground reaction curve is significantly affected by seepage forces. In this study, the theoretical solutions of ground reaction curves were derived for both the dry condition and the seepage forces. The theoretical solutions derived were validated by numerical analysis. The ground reaction curves with the support characteristic curve were also analyzed in various conditions of groundwater table. Finally, the theoretical solutions of the ground reaction curve derived in this study can be utilized easily to determine the appropriate time of support systems, the stiffness of support system and so forth for the reasonable design.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.25-33
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• 1999

The recent emergence of biofiltration as a cost effective waste-gas control technology has stimulated in European countries and the USA. Biofiltration of soil vapor extraction off-gas from gasoline contaminated site was simulated in lab-scale in this study. A filling material used was a compost. This study was conducted to evaluate biofiltration characteristics of the compost material for gasoline off-gas. TPH elimination capacity at the gas loading rate of about 50g/$\textrm{m}^3$((filling material)/hr was circa 40g/$\textrm{m}^3$((filling material)/hr. Removal rate of xylene was the highest among BTEX. while it was the lowest in case of bezene. The maximum elimination capacity of the compost was about 1.5g/$\textrm{m}^3$((filling material)/hr for benzene. More than 95% of trimethylbenzene and naphtalene were removed below the loading rate of 0.7g/㎥(filling material)/hr. About 80% of total TPH and BTEX were removed by biodegradation.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.3-15
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• 1999

This paper includes the basic experimental results performed for developing an innovative and technologically feasible process wherein gaseous ozone, a powerful oxidant. is injected directly into vadose zone by which in-situ chemical degradation of semi- or, non-volatile petroleum product such as diesel fuel is derived. As ozone gas injected continuously(50mL/min, 119.0$\pm$6.1mg/L) into soil packed columns artificially contaminated with diesel fuel(initial concentration 1,485mg-DRO/kg/soil), the removal rates at the inlet and outlet point of 14hrs-operated column are 87.9% and 100.0%, respectively. On the other hand, soil vapor extraction system showed less than 30% of removal rates of residual diesel both at the inlet and outlet samples under the same experimental conditions which confirms the limited treatability of SVE in diesel contaminated soil.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.688-692
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• 2006

산지 소하천 유역을 대상으로 물순환 과정을 규명하기란 대단히 어려운 실정이다. 1차적으로는 수문자료의 부재가 제일 크며, 자료가 있다 하더라도 홍수기 중심 및 단기간 자료의 축적에 불과하다. 이중 설마천 시험유역은 한국건설기술연구원의 11년간 운영경험을 바탕으로 비교적 장기간의 수문자료를 축적하고 있다. 최근 6년간은 신뢰할 만한 양질의 수문자료를 구축하였으며, 현재는 신뢰도의 완성을 높이는 연구가 활발히 진행 중에 있다. 설마천 시험유역의 유역의 물순환 구조는 자연계의 유입과 유출이 지배적이며, 이들의 수문성분을 규명하기 위해서는 각각의 수문성분들의 관측 및 해석이 필요하며, 각 수문성분들의 물수지 분석을 통하여 정량적인 합의 결과를 가시적으로 확보함이 매우 중요하다. 신뢰도와 정확성에 근거한 관측자료를 이용한 물수지 분석결과는 수문성분들의 총체적 표현이라 할 수 있는 모형(model)의 중요 입력자료이며, 모형의 분석결과를 검증할 수 있는 중요한 기준이 된다. 모형의 결과와의 비교 검토를 통해 산지 소하천 유역의 물순환 관계를 규명하는 기반을 확보하게 될 것이다. 본 연구에서는 신뢰성 있는 수문관측 자료를 이용하여 물수지 분석을 수행하였다. 물수지 분석의 대상유역인 설마천 시험유역의 신뢰할 만한 관측자료에는 강우량, 유출량, 지하수이용량이며, 증발산량 산정을 위한 기상관측 및 대형증발계를 통한 실제 증발량 관측은 이루어지나 유역을 대표하는 증발산량의 관측이 연속적으로 이루어지지 못하는 실정이다. 그러나, 설마천 시험유역은 소규모이며, 대체로 동질성 있는 유역이라고 가정하여 1개 기상관측소에서 운영하는 기상자료를 이용하여 증발산량을 산정하고 물수지에 적용하였다. 또한, 그 동안 관측하지 못했던 지하수위 관측을 실시함으로써 정확한 물순환 해석을 할 수 있는 기반을 확보 하였으며, 가용한 장 단기간의 관측자료와 물수지 분석 연산식의 추정치를 바탕으로 관측자료에 의한 물수지 분석을 수행하였다. 분석 결과로 산지 소하천 유역인 설마천 시험유역의 각 수문요소의 물이동간의 정량적인 값을 알 수가 있었으며, 앞으로 추가적이고 지속적인 수문모니터링이 운영되고 물순환 해석 모형에 의한 검증이 수행된다면 정량적인 물순환 관계를 규명할 수 있을 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.