• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.223-223
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• 2019

기후 변화에 따른 해수면 상승은 해안 지하수의 해수침투를 야기해 해안 지하수의 염도를 증가시킨다. 또한 해수면 상승은 토양 염류화를 심화시켜 농작물에 피해가 발생하며, 지하수위를 증가시켜 불포화대의 토양두께가 감소한다. 이처럼 지하수 해수침투가 발생하는 포화대와 토양 염류화가 발생하는 불포화대는 서로 연관되어 있지만, 대부분 포화대와 불포화대 연구는 별도로 진행되어왔다. 본 연구에서는 해안 간척지의 해수면 상승에 따른 포화대의 해수침투 및 불포화대의 토양염류화 영향을 연계하여 모의하였다. 포화대 모의는 미국지질조사국(United States Geological Survey, USGS)에서 개발한 3차원 이송확산 모델인 SUTRA, 불포화대 모의는 미국환경청(United States Environmental Protection Agency, USEPA)에서 개발한 1차원 이송확산모델인 VADOFT를 사용하였다. 해수면 상승 시나리오는 IPCC에서 공표한 바와 같이 RCP 4.5와 RCP 8.5 시나리오를 사용하였고, 미래 2100년까지 자료를 사용하였다. 해수면 상승 시나리오에 따라 해수침투 및 토양염류화 면적 그리고 지하수위 및 불포화대 토양두께를 정량적으로 산정하였다. 한반도 91개 간척지에 대해서 모의를 수행하였고, 과거 대비 미래 후반기 RCP 4.5 시나리오에서는 지하수 해수침투 면적이 $82.19km^2$, RCP 8.5 시나리오에서는 $83.71km^2$ 증가하는 것으로 나타났다. 또한 토양 염류화 면적은 과거 대비 미래 후반기 RCP 4.5 시나리오에서는 $22.25km^2$, RCP 8.5 시나리오에서는 $24.86km^2$ 증가하는 것으로 나타났다. 담수호 또는 저수지가 있는 대상 지역에서는 해안선으로부터 거리 및 관리 수위가 해수 침투를 야기시키는 중요한 요인으로 나타났으며, 해수침투 저감을 위해서는 해안선 인근 저수지 수위의 적절한 유지관리가 필요할 것으로 판단된다. 본 연구에서는 해수면상승에 따른 해안선의 위치변화와, 기존 관정에서의 양수량, 강수량 변화를 고려하는 것에 한계가 있기 때문에, 향후 위의 세 가지 사항을 복합적으로 고려한 추가 연구가 필요하다고 사료된다.

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.181-184
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• 2002

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.75-80
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• 2003

Understanding the seawater infiltration into tidal flat sediments is very important, because it is significantly correlated with the supply of dissolved oxygen, nutrients and organic matter to benthic organisms for survival. However oil blocks interstitial spaces of sediments, reduces seawater infiltration and results in the decrease in oxygen, nutrients and other food supply to benthic communities. The penetration depth of the stranded oil into the sediments is one of the most significant information to know the effect of spilled oil on biological communities and to set up a cleaning method. So we initiated this study to quantify the penetration behavior of spilled oil and to evaluate the influence of the penetrated oil on seawater infiltration in tidal flat environment and its ecological implications. The penetration depth of the crude oil into the tidal flat sediments was two times deeper than that of the fuel oil C, and the depth was significantly affected by stranded oil volume. However, the penetration depth of stranded oil was abruptly dropped at first falling tide but not significantly fluctuated after that. Moreover, hydrocarbon concentration showed the highest within the upper 2 cm. Seawater infiltration was decreased in proportion to the stranded oil volume. The seawater infiltration was more affected by the penetrated fuel oil C about 1.7 times than the crude oil, because the interstitial spaces of the top of sediments were more cleared by the fuel oil C. Therefore, quick cleaning actions for penetrated oil will be necessary for recovery of seawater infiltration because the seawater contains oxygen and nutrients necessary for the survival of benthic organisms in tidal flat.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.3
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• pp.134-139
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• 2005

The purpose of this study is to quantify the penetration behavior of spilled weathered oil and dispersed oil and to evaluate the influence of the penetrated oils on seawater infiltration in tidal flat environment. The penetration depths of the spilled oils into the tidal flat sediments were gradually deeper according to increase the stranded oil volume. The penetration depth of stranded oil were abruptly dropped at first falling tide, but were not significantly fluctuated after that. Moreover, hydrocarbon concentration was most high within the upper 2 cm. Seawater infiltration was decreased in proportion to the stranded oil volume. Dispersed oil was easily permitted the seawater infiltration than weathered oil and crude oil. Therefore, quick cleaning actions fur penetrated oil will be required far recovery of seawater infiltration, because the seawater contains oxygen and nutrients required for the survival of benthic organisms in tidal flat.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.3-11
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• 2001

To know the seawater infiltration into tidal flat sediment in coastal area is very important, because it is significantly correlated with the infiltration and transportation of pollutants in soil, the supply of dissolved oxygen, nutrients and organic matter to benthic organisms for survival of benthic organisms and the seawater purification. So, we set up purpose to clarify the infiltration behavior of seawater by wave action in tidal flat, to clear the effects of slope of tidal flat and breaking wave height on seawater infiltration and to quantify the infiltration volume of seawater. For purpose, the seawater infiltration was studied with visualization method by using coloring tracer and transparent glass beads replaced as natural sediment in model tidal flat. Specific conclusions derived from this study are as follows. The semi-circular type infiltration of seawater by wave action into saturated sediment was a new infiltration behavior that was not considered in previous studies. The infiltration rate of seawater was increased with increasing of breaking wave height and slope of tidal flat. However, the effects of the slope was bigger than that of breaking wave height on seawater infiltration into tidal flat sediments. It was possible to calculate the infiltration volume of seawater by wave action in natural tidal flat sediment and in fields. Therefore, we can point out that wave action play an important role in the supply of dissolved oxygen, nutrients and organic matter to benthic organisms, transportation or diffusion of pollutants and seawater purification. So, we hope to be studied the supply of food to benthic organism, pollutant transport and seawater purification on the base of these results.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.119-121
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• 2007

• Geophysics and Geophysical Exploration
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• v.5 no.1
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• pp.56-63
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• 2002

Tracing the history of study, problems of seawater intrusion are commonly investigated with electrical techniques because seawater saturated zone is indicative of the low resistivity anomaly. There we, however, silt and mud layers in the western and southern coastal areas of Korea, so we may make a mistake in case we determine seawater intrusion only with resistivity survey. Hence, reference IP survey was carried out in Kimje, Jeollabuk-Do and Youngkwang, Jeollanam-Do in order to decide whether or not the area is under the influence of seawater intrusion. With the use of a electric field cable to minimize EM coupling, we obtained more accurate results by appling reference If technique measuring simultaneously wavelet of current as well as potential. With the aid of reference IP technique, it is possible that we can exactly evaluate seawater intrusion by discriminating seawater saturated area (no IP effect) from very highly conductive layer composed of clay mineral (high IP effect).

• The Journal of Engineering Geology
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• v.10 no.2
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• pp.172-188
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• 2000

This paper presents the state of art and the role of geophysical exploration techniques with evaluating the trend of domestic and worldwide seawater intrusion research, and illustrates advanced techniques obtained through the project of 'Development of the techniques for estimation, prediction, and prevention of seawater intrusion' funded by the Ministry of Science and Technology of Korea. The advanced geophysical interpretation was achieved by adding the digital geophysical logging data. DC resistivity and TEM monitorings were applied to determine whether or not the seawater intrusion was in progress. Induced Polarization technique using electric current monitoring channel was introduced to discriminate seawater contaminated zone from highly conductive layer caused by clay minerals. A conceptual model was suggested with spatial visualization of the study area to predict the diffusion of seawater contamination. Finally, the future work of the development of geophysical techniques was suggested with the base of the present level of them.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.2
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• pp.61-72
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• 1997

With increasing activities for groundwater withdrawal and for the construction of underground cavern in the coastal areas, the seaward flow of groundwater has been disturbed or even reversed, resulting in seawater intrusion in aquifers. This phenomenon would be attributed to the freshwater contamination and the corrosion of steel materials. The hydrogeological and geochemical investigations have performed to characterize the seawater intrusion into the underground caverns located in the coastal area. Assumimg the inland aquifer as unconfined one, we have found out that the theoretical interface of freshwater-seawater is far different from the pathways identified. In the study site, the main pathways of seawater intrusion into the underground cavern are characterized as the sub-horizontal fractures (zones). The seawater intrusion in granitic terrane would depend mainly on the characteristics of conductive fracture system developed along the coastal area.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1030-1034
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• 2005

The purpose of this study was to clarify the penetration behavior of particulate matters by wave and tidal actions in sandy beach located in enclosed bay and to evaluate the effect of stranded oil on penetration of particulate matters. Experiments were rallied out using a model sandy beach facility. The particulate matters penetrated into saturated sediments by wave action from breaking wave run-up point with a semi-circular forming in low energy beach as enclosed bay. On the other hand, the penetration velocity of the particulate matters was to be faster according to the increase of slope and breaking wave height. The particulate matters by tidal action penetrated into the sediments at an angie of 45 degrees in the direction of porous water flow. The stranded oil completely blocked the penetration of the particulate matters into the sediments. These results indicate that the penetrated oil prevents the penetration of the particulate matters into the sediments and, therefore, results in the reduction in the supply of plankton, bacteria and organic detritus for the benthic organisms in the sandy beach.