Düzenli depolama alanlarının taban sızdırmazlığında gerekli olan kil kalınlığının tespiti

Depending population growth and technological developments of world countries, solid waste rate is constantly changing and rising. Solid wastes brought by the continuously producing societies affect the natural environment in the negative direction. Solid wastes generated should be kept absolutely and threats to the environment must be reduced to a minimum. Nowadays as a solution to this pollution problem “regular waste storage method” has become a necessity in all developed countries. Regular waste storage method prevents the waste from harming the environment and negative effects on people's habitats are eliminated. In this study, the clay thickness used in the landfills of the regular storage areas was tried to be determined. The 30 cm top layer clay, layer of High Density Polyethylene (HDPE) membrane, geotextile material and finally only 60 cm clay layer is used for loam seal in Turkey and developing countries that transferred to solid waste landfill system lately. However, developed countries that used this system many years ago have been advanced waste storage standards and criteria in parallel with the increasing environmental conscious. Besides compressed clay layers, few layers of geomembrane and geotextile usage; transition layers, intermediate layers, geonet or geocomposite layers and basic layers which were created from recycled materials are used in compliance with these standards. Correspondingly, these layers were increased so as to avoid the excessive leakage created by mixture of rain water with wastes and also to avoid the contact of solid wastes with people, animals and plants. Intermediate layers, gas discharge layers, compressed clay, geomembrane and geotextile layers and drainage layers were started to be used instead of one layer of clay. Countries that noticed and understood the deficiencies and technical incompetence of this system, after using many years, increased the standards and criteria of the system. The goal of implementing a new system which was analyzed thoroughly and determined the most appropriate system is aimed to consider the conditions such as ground, topographical pattern, geological and hydrogeological criteria, climate and vegetation of the country. Storage base sealing is the most important phase geotechnically to control the leakage caused by storage systematically. Common existence of clay soil makes the implementation of impermeability layer widespread. Factors affecting the permeability of clayey soils are compaction method, compaction energy, and moisture content of clay, pellet size of clay, materials included and the degree of link between the soil layers. In this study, the clay whose permeability is provided 1x10-7 m/s or less thorough experiments in laboratory will be placed in different thicknesses (20 cm, 40 cm, 60 cm, and 80 cm) in the artificial storage glass container which is named a miniature field system. Then it was decided to use 8 mm thick glass to avoid breakage of containers. Then the leachate was poured on to the top of clay until completely cover the clay about 20 cm thickness. Each experimental setup was carefully observed for 9 months. Any changes in the leachate level (in cm), possible leakages and wetting in the clay (in cm) were noted down in tables within daily, weekly and monthly bases. Thus, the optimum thickness of clay used in the formation of impermeable layer in regular solid waste storage area was questioned and investigated.