• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2001.09a
• /
• pp.188-190
• /
• 2001

This study presents procedures and analysis methods for well known two field soil permeability tests, disc-tension infiltrometer and Guelph permeameter. Some case tests are demonstrated and then some problems involving the tests were clarified. This study may be helpful for practical field hydrogeologists.

• Journal of the Korean Society of Groundwater Environment
• /
• v.4 no.4
• /
• pp.191-198
• /
• 1997

The Seokdae municipal waste landfill was filled from 1987 to 1993. A disk tension infiltrometer was used to estimate the saturated hydraulic conductivity of the upper part of landfill cover. The estimated saturated hydraulic conductivity ranges from 2.2$\times$$10^{-4}$~8.1$\times$$10^{-3}$ cm/sec. Net infiltration through the Seokdae municipal waste landfill is estimated from precipitation data, hydraulic conductivity and reported landfill profiles by using an unsaturated flow model, HYDRUS. Total infiltration rate is estimated to be 939 ㎥/day. Leachate level rise and leachate seepage are computed by adopting a simple model.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.5
• /
• pp.259-267
• /
• 2006

Hydraulic conductivity is the rate of water flux on hydraulic gradient. The van Genuchten Mualem (VGM) model is frequently used for describing unsaturated state of soils, that is composed with the function of soil water potential and soil water content and requests various parameters. This study is to get the value of VGM parameters used Rosetta computer program based on neural network analysis method and to calculate VGM parameters. VGM parameters included Ko(effective saturated hydraulic conductivity), ${\theta}r$(residual soil water content), ${\theta}s$(saturated soil water content), L, n and m. The unsaturated hydraulic conductivity at 10 kPa was calculated by using Rosetta program. Unsaturated hydraulic conductivities of 17 soil series at 1, 3, 5, 7 kPa were also obtained by applying saturated hydraulic conductivity by disk tension infiltrometer based on Gardner and Wooding's equation. Water flow at the water potential of 3 kPa was very low except Namgye, Hagog, Baegsan, Sangju, Seogcheon, Yesan soil series. Unsaturated hydraulic conductivity at 1 kPa showed the highest value for Samgag soil series and was in order of Yesan, Hwabong, Hagog and Baegsan soil series. Those of Gacheon, Seocheon and Ugog soil series were very low. When the value by VGM was compared with the value by disc tension infiltrometer, there was a tendency with exponential function to soils without gravel but there was no tendency to soils including gravel. Conclusively, it would be limited that VGM model for unsaturated hydraulic conductivity analysis applies to Korean agricultural land including gravel and having steep slope, shallow soil depth.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 1996.11a
• /
• pp.102-105
• /
• 1996

난지도 매립지는 매립충의 불균질성과 고온의 침출수 및 가스의 흐름이 동시에 복합적으로 일어나는 현상 때문에 수리지질학적으로 매우 복잡한 지역이다. 난지도의 수문층서단위 조사와 디스크-장력 침투계(Disc tension Infiltrometer)로 불포화대 수리 특성을 추정하였으며 가스 거동 현상을 이해하기 위해 지온을 측정하였다. 매립지 주변의 지하수위 변화를 조사하기 위해 양수정과 다중-수위관측정(Multi-Level Monitoring Well)에서 수위변화를 관측하였다. 불포화대 수리특성과 기상자료를 바탕으로 매립지로의 순침투량을 추정하였다. 이것을 근거로 총 침출수 발생량을 추정하였으며, 기저 지하수면 상부에 분포하는 포화 침출수대, 즉 부유침출수의 생성 메카니즘에 대한 연구도 수행하였다.

• Journal of the Korean Society of Groundwater Environment
• /
• v.3 no.2
• /
• pp.80-94
• /
• 1996

The Nanjido Landfill has recently become one of the most important environmental sites for a hydrogeological study. Hydrogeological study was performed by understanding the current situation, analyzing hydrogeological information, and constructing a hydrogeological data base. The constructed data base was used for the analyses of several important phenomena in the Nanjido Landfill. Saturated hydraulic conductivity and underground temperature were measured. Based on the hydraulic conductivity and rainfall data, net infiltration rates were estimated. Leachate production rates are estimated by using the data base. The data base and a hydraulic model were used to understand the formation of the so called floating leachate layer.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.1
• /
• pp.70-78
• /
• 2009

Floodplain areas of major South Korean rivers were determined by analyzing topographical maps and hydraulic properties of floodplain soil were measured using disc tension infiltrometer. To assess the possibility of treating secondary effluents of municipal wastewater with floodplain soil, a computer code for the analysis of unsaturated flow in soil was employed along with searches conducted in the literature. Based on the data generated, an estimate of total floodplain filtration capacity in Korea was obtained. The results of our study reveal that Korean floodplains have surface soil that is adequate for treating water. Moreover, the distributions of floodplains are substantial over the entire reaches of the rivers, indicating that the conditions are favorable for floodplain filtration as additional treatment of secondary effluent. The capacity of floodplain filtration in Korea is circa 182,000,000 $m^3$/day and most of the rivers are estimated to have enough capacity of floodplain filtration to meet all the secondary effluent, indicating that this technology may be expected to make further improvements on river water quality. Furthermore, this method may also be applied to better the source-water quality for drinking water.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.2
• /
• pp.103-109
• /
• 2009

Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, and have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for classification of hydrologic soil group (HSG) of soils originated from limestone by measuring the infiltration rate of surface soils and percolation rate of sub soils. Soils used for the experiment were 6 soils in total : Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. Particle size distribution and organic matter content of the soils were analyzed. HSG, which was made by USDA NRCS(National Resources Conservation Service) for hydrology, of Gwarim series with O horizon of accumulated organic matter was classified as type A which show the properties of low runoff potential, rapid infiltration and percolation rate. HSG of Mosan series, which has high gravel content and very rapid permeability, was classified as type B/D because of the impermaeble base rock layer under 50cm from surface. HSG of Jangseong series with shallow soil depth was classified as type C/D owing to the impermaeble base rock layer under 50cm from surface. HSG of Maji series was type B, and HSG of Anmi series used as paddy land was type D because of slow infiltration and percolation rate caused by the disturbance of surface soil by puddling. HSG of Pyeongan series having a sudden change of layer in soil texture was type D because of the slow percolation rate caused a the layer.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.2
• /
• pp.132-138
• /
• 2009

Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for making PTF(Pedo-Transfer Function) for Kfs(field saturaton hydraulic conductivity) estimation, and for investigating the relation between soil particle distribution and the infiltration and percolation rate in soils originated from limestone. Soils used for the experiment were 6 soils of Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate for the soil were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. The particle size distribution and organic matter content of the soils were analyzed. Kfs was not related with sand, silt, clay, and organic mattrer (OM) content because of forest soils which contained high gravel, pebble, and cobble content, and O layer with high OM content. After Mosan soil series and O layer of Gwarim series were excluded for the data analysis, Kfs was explained as a linear function with sand and clay content and a exponential function with OM content. As a result, the PTF equation was obtained as Kfs=-4.20558+0.479706*(S)+0.023187*exp(1.829*OM) ($R^2=0.6558^{*}$).

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.1197-1204
• /
• 2008

강원도 남부(영월)와 충북 제천, 단양 등지에 널리 분포하는 석회암에서 유래된 토양은 점토 및 철분함량이 많은 식질계 토양이며 pH와 염기포화도(Base Saturation)가 높은 붉은색 토양이다. 이 토양은 식양질과 식질 등의 세립(細粒)질로만 구성이 되어 있고 자갈이 있는 토양으로 분류된다. 따라서, 토양의 침투 및 투수속도가 우리나라 토양의 주 모재인 화강암이나 화강편마암 유래 토양과는 다른 양상을 보인다. 본 연구는 세립질 특성을 보이는 석회암 유래 토양의 지표면에서의 침투속도와 토양층위별 투수속도를 측정해 복잡하게 세분되어 있는 토양의 종류를 수문학적인 목적에 따라 단순화하기 위해 만든 수문학적 토양유형을 분류하고자 하였다. 실험을 위해 이용된 토양은 과림, 모산, 장성, 마지, 안미, 평안통의 6개 토양이었고 장력 침투계(Disc tension infiltrometer)와 투수속도 측정계(Guelph permeameter)로 침투 및 투수속도를 측정했다. 현장측정 이후 추정식의 개발을 위해 토양층위별로 시료를 채취하여 실험실조건에서 입도분포, 유기물함량을 측정했다. 토양통별 침투 및 투수속도를 측정한 결과는 유기물 층이 존재하는 과림통은 공극이 많고 토층 내에 나무 및 식물뿌리가 존재해 전체적으로 침투 및 투수속도가 빠른 특성을 보여 수문유형을 A로 분류되었다. 모산통은 토층 내에 자갈함량이 아주 높고 투수속도가 다른 토양에 비해 월등히 빠른 특성을 나타냈으나 50cm이내에서 암반층이 존재하는 관계로 수문유형이 C로 분류되었다. 토층이 깊지 않은 장성통은 토층 내에 나무 및 식물뿌리가 많고 암석노출지가 존재해 침투속도가 빠름에도 불구하고 C 수문유형으로 분류됐다. 자갈이나 잔돌이 많은 마지통은 잔자갈이 존재하고 침투나 투수속도가 빠른 편으로 A유형이었다. 논으로 사용되는 안미통은 다른 석회암 유래토양에 비해 토층이 깊은 편이며 석회암 충적층에서 유래된 토양으로 선상지 및 곡간지에 분포한다. 관개된 상태에서 로타리 작업에 의해 표토의 특성이 교란되는 논으로 이용되는 특성 때문에 침투 및 투수속도는 느려 C유형으로 분류됐다. 잔돌이 존재하는 평안통은 석회암 붕적, 퇴적층으로부터 유래된 토양으로 산록경사지 및 선상단구에 분포하며 표토층인 A층에서 중입상구조를 보이며 공극이 많고 작물뿌리가 매우 많아 침투속도는 빠르나 B층에서는 점토 함량이 감소했다 증가하면서 토성이 급격히 바뀌는 특성을 나타내 투수속도는 느린 값을 보였으나 수분학적 토양유형은 B유형으로 분류됐다.