• 지질공학
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• 제16권3호
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• pp.301-306
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• 2006

석조구조물의 주변 지반침하는 구조물 붕괴의 위험을 내포하고 있어 지반의 모니터링이 반드시 수행되어야 한다. 대표적인 지반침하 원인으로는 지하수위 변동에 의한 지반의 포화와 불포화 현상으로 지반의 공극률 내지 유효공극률 감소에 의해 발생된다. 이러한 지반 물성치의 평가는 유전율상수 반응으로부터 파악이 가능하다. 유전율상수 변화는 매질의 공극, 토입자, 공기 및 물 등의 물리적 특성 변화로부터 측정되기 때문에 지반의 포화 및 불포화 변동에 의한 유전율 반응으로부터 지반침하 모니터링이 가능할 것으로 판단된다.

• 한국물환경학회지
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• 제23권2호
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• pp.201-205
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• 2007

This paper reports the amount of $^{222}Rn$ and $^{238}U$ in 18 sites of ground water and 30 sites of surface water. The instrument used to count $^{222}Rn$ activity was the liquid scintillation counter (LSC) which could resolute ${\alpha}$ and ${\beta}$ radiations. And $^{238}U$ was analyzed by the inductively coupled plasma (ICP). Radon and Uranium were not detected in raw and treated water which were sampled in a water treatment plant. However, radon ($^{222}Rn$) was high concentration in ground water from Jeon-la, Gang-won. So was uranium ($^{238}U$) in case of ground water from Gang-won, Choong-chung. Radon ($^{222}Rn$) activities were detected less than 15 pCi/L at 5 sampling points, 15~300 pCi/L at 7 sampling points, 300~4000 pCi/L at 6 sampling points. However, Radon ($^{222}Rn$) activities of all ground water samples were less than 4,000 pCi/L, which was bellow American Alternative Maximum Contamination Level (AMCL). Uranium ($^{238}U$) concentrations were less than $0.1{\mu}g/L$ at 5 sampling points, from $0.1{\mu}g/L$ to $20{\mu}g/L$ at 13 sampling points. Uranium was not detected in about 30% of the whole samples, but the concentration ranged from relatively low to high concentrations depending on the sampling point. The minimum detectable activity (MDA) of radon was 15 pCi/L. and the detection limit of uranium was $0.1{\mu}g/L$.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권2호
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• pp.61-76
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• 2011

This study was objected to provide suggestions for best management practices to restore the cultural and historical values of the wells in Palaces as well as their water qualities. Water resources in the five Palaces in Seoul Metropolitan, including Gyeongbokgung, Changdeokgung, Changgyeonggung, Jongmyo Shrine, and Deoksugung, were surveyed for their physical flows and chemical compositions from April to July in 2010. Ground waters in most wells were found at depths within 5 m from the ground surface, showing typical water-table aquifer systems. Hydraulic gradients indicate water resources in Gyeongbokgung, Changdeokgung, and Changgyeonggung flowing toward south, and toward east in Deoksugung area. Especially, water-level fluctuation data at S-10 in Deoksugung implied the influence of groundwater discharge facility. In Jongmyo Shrine, water was not detected in wells, indicating the water level was lower than the well depth. Based on the water chemistry and stable isotope analyses, water resources and their qualities appeared to be formed by the water-rock interaction along the groundwater paths. S-10 (Deoksugung) and S-14 (Changgyeonggung) samples were contaminated with nitrate ($NO_3$) in levels of higher than Korean drinking water standard, 10 mg/L as $NO_3$-N, but once in four sampling campaigns. In the situation that water resources in Palaces still maintain natural characteristics, the materials that will be used for the restoration and improvement of the Palace water supplies should be carefully selected not to disturb the natural integrity. In addition, because the wells are located in the center of metropolitan area, a systematic monitoring should be applied to detect and to manage the potential impacts of underground construction and various pollution sources.

• 물과 미래
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• 제6권2호
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• pp.19-29
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• 1973

The progressive contamination of water resulted from man's activity and the use of fertilizers is not restricted only to surface water, but also the shallow groundwater is affected. This type of groundwater contamination is mainly restricted to areas composed of permeable, nonconsolidated sediments forming a shallow aquifer. The chloride and the sulfate resulted from man's activity and the use of fertilizers were measured to study the variations of the groundwater contamination. In general, (1) When water level rises, the rate of groundwater contamination becomes less and when water level declines, the rate of contamination is increased. (2) The highly contaminated season is the early-summer and the less contaminated season is the winter or after rainy season. (3) The groundwater in weathering zone without covering layer. (4) The degree of contamination of wells is increased with the increase of well depth and lowing the water table, because of increasing contaminated water from enlargement of the area of influence of the well.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2009년도 학술대회 초록집
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• pp.119-123
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• 2009

지하수 수위 변동에 따른 중력 변화를 이동식 기조력 중력계(PET)를 이용하여 충청남도 금산군에 위치한 국가 지하수 관측소(금산 금산 지하수관측소)에서 측정하였다. 중력 탐사는 2008년 11월부터 2009년 9월까지 약 10개월에 걸쳐 수행되었다. 또한 중력탐사가 수행되는 기간 동안 지하수 수위변화에 대한 자료도 얻었다. 얻어진 중력 자료로부터 지하수의 수위변동에 의한 효과만을 추출해 내기 위하여, 대기압에 의한 효과, 조석 효과, ocean loading 효과, polar motion과 drift 효과를 제거하였다. 이렇게 보정된 중력 자료를 관측정에서 측정한 지하수 수위변동과 직접 비교하여 중력 신호에 대한 지하수 수위 변동의 영향을 알아보았다. 또한 6월에는 지하수 관측소에 대한 양수 작업이 있었다. 이 작업이 수행되는 동안 지하수의 수위 강화와 충전이 있었으며, 이와 연관된 중력변화도 매우 성공적으로 관측되었다. 지하수 수위변동에 의한 중력 효과의 관측은 대수층의 water mass balance와 수자원에 대한 모니터링에 있어서 아주 유용하게 이용될 것으로 보인다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.32-35
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• 2006

The validation of a groundwater source heat pump system installation site is estimated by bydrogeothermic model ing. The hydraulic characteristics of the aquifer system is evaluated from pumping and recovery tests. In addition, the temperature distribution by the pumping and the injection of groundwater, and water level fluctuations are simulated by numerical modeling. The total cooling and heating load for the building is designed as 120RT(refrigeration ton) and the ground water source heat pump system covers 50RT as a subsidiary system The scenario of heat pump operation is organized as pumping and inject ion of groundwater that is performed for 8 hours per day in cooling mode for 90 days during the summer season The heat transfer by the injected warm water is limited near the inject ion wells in the simulated temperature distribution. The reason is that the given operation time is too short to expect broad thermal diffusion in large volume of the aquifer in the simulation time The simulated groundwater level and temperature distribution can be used as important data to develope an energy effective pumping and injection well system. Also it will be very useful to evaluate the hydraulic capacity of a target groundwater reservoir.

• 산업기술연구
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• 제20권A호
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• pp.257-267
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• 2000

It was difficult to apply conventional excavation methods in some sections from Seoul to Pusan high speed rail road construction of 1 lot 2, due to highway concrete road, gas pipe, water pipe and nearby factories with automatic control system machine. To excavate safely and efficiently in these sections new blast patterns were employed within allowable blast vibration level, by test blast and controlled vibration by sequential blast. Behaviors of the rock mass including convergence and displacement around tunnel were measured with construction works and the crack width in concrete wall was also monitored for controlling allowable limits. The results can be summarized as follow : 1. The allowable blast vibration level in structure site is less 1.0cm/sec for highway concrete, 0.5 cm/sec for gas pipe, water pipe and building housing and 0.3 cm/sec for automatic control system machine. 2. The convergence displacement, single rod extensometer and multi rod extensometer around tunnel and cracks in concrete wall were measured, it was confirmed that the measured values were converged within allowable level. 3. The empirical formular of ground vibrations with 90% confidence lines for PD-3 was given as follow. $$V_{90%}=45.549({\frac{D}{\sqrt{W}}})^{-1.353}$$

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.764-771
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• 2010

The stability analysis method of an unsaturated slope considering the suction stress was performed on the infinite sand slope. During drying and wetting processes, the Soil-Water Characteristics Curve (SWCC) of the sand with the relative density of 75% was measured using the automated SWCC apparatus. Also, the Suction Stress Characteristics Curve (SSCC) was estimated. Based on these results, the stability analysis of an unsaturated infinite slope was carried out considering the slope angle, the weathering zone and the relative change in friction angle as a soil depth. According to the result of slope stability analysis, the safety factors of slope were less than 1 when the slope angles were more than $50^{\circ}$. The safety factors of slope tend to increase with increasing the depth from the ground surface. Especially, the safety factors have a tendency to increase and decrease above near the ground water level due to the suction stress. The maximum safety factor of slope in this analysis was occurred at the Air Entry Value (AEV) of drying process. The influence range of suction stress above the ground water level can be found out and can be defined as the funicular zone which means the metric suction range from the air entry point to the point of residual volumetric water content.

• 한국방사선학회논문지
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• 제13권6호
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• pp.847-856
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• 2019

오늘날 경제의 발전과 함께 여러 가지 환경 문제가 발생했다. 자연스레 사람들은 환경에 대한 관심이 높아졌으며 특히 식수에 대한 안전성과 오염도 조사에 대한 중요성이 부각되고 있다. 우리나라 국민들이 식수로 이용하는 지하수에서 우라늄 및 ²²²Rn 이 다수 지역에서 검출되고 있다. 따라서 이 연구는 지하수 내포함된 ²²²Rn 농도를 측정하는데 보다 정확한 측정을 위한 방법을 알아보고자 한다. 실험은 알파, 베타 펄스의 분석이 용이한 펄스파형분석 기능을 가진 저 준위 액체섬광계수기를 이용하여 실험하였다. 지하수 시료와 혼합하는 섬광체의 조제, 유효기간은 시간이 지날수록 검출값은 낮아지고, 에너지 스펙트럼도 낮은 쪽으로 channel 이동이 있었다. 섬광체의 구입시기가 오래 될수록, 개봉한 후 방치시간이 지날수록 검출값이 낮아짐을 확인했다. 사용목적이 다른 섬광체를 사용했을 경우 channel 이동으로 에너지를 확인할 수 있다.

• 한국농공학회논문집
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• 제48권2호
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• pp.13-23
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• 2006

In Korea, upland irrigation generally depends on the ground water or natural rainfall since irrigation water supplied from dams is mainly used for paddy irrigation, and only limited amount of irrigation water is supplied to the upland area. For the stable security of upland irrigation water, storage level of irrigation dams was simulated by the periods. A year was divided into 4 periods considering the irrigation characteristics. Through the periodical management of storage level, water utilization efficiency in irrigation dams could be enhanced and it makes available to secure extra available water from existing dams without new development of water resources. Two study areas, Seongju and Donghwa dam, were selected for this study. Runoff from the watersheds was simulated by the modified tank model and the irrigation water to upland crops was calculated by the Penman-Monteith method. The analyzed results showed that relatively sufficient extra available water could be secured for the main upland crops in Seongju area. In case of Donghwa area, water supply to non-irrigated upland was possible in normal years but extra water was necessary in drought years such as 1998 and 2001.