김포매립지의 수문지질학적 특성에 관한 연구

Abstract

Kimpo landfill site was reclaimed 10 years ado. After the reclaimation, the land has not been used for any purpose. The land was selected for the waste-fill site of Seoul Metropolitan Area in 1994. The Land reclaimed from tidal flats has not been studied enough in hydrogeologic aspect. This study was aimed to provide the information of environmental properties at Kimpo landfill site: the climatic and hydrologic characteristics, physical and chemical properties of the sediments, the geologic structures, and the elevation of the underground water. Samples were obtained using the vibracorer into the depth of 6m without disturbance. The results are as fol1ows. 1. Summer season' s concentration rate of precipitation and surface runoff are 47% and 57%, respectively. 2. The mean diameter of sediments in Kimpo landfi1l site is silt size(5-6 φ ). The contents of silt and clay are 60-80% and 10-20%, respetively. But the content of the sand(0.0625-2mm) is different from site to site. 3. The permeability of the sediments is in the range of 1.0 x 10-5cm/sec - 9.0 x 10• 7cm/sec. The permeability of most of the samples exeeds the exclusion criteria for the ladfill site(1.0 x 10-7 cm/sec). 4. The organic matter contents are relatively low(1-7%). The O.M. contents of the upper layer are higher than those of the lower layer. This means that the O.M. of the upper part was oxidized through the contact with the air. 5. pH and the electric conductivity(E. C.) are higher in upper part than the lower part. This result shows that the soluble solute is leaching out rapidly. 6. The geology in this study area is composed of coastal sediment layer, weathered soil layer, weathered rock layer and bedrock layer. The upper sediments have the characterictic of the tidal flat, and get thicker in depth toward the coast. 7. The underground water level is between 1-3m below the surface. The flowing direction is towards the lower tidal creek or coastal side.