Hydrogeological investigations for the determination of the solid waste disposal area of the Torbalı Plain

ABSTRACT The urbanization and rapid industrialization create many environmental problems around unconfined alluvium aquifer. Especially, one of the serious problem of the groundwater polltion is decided as solid as dumping areas. Recently, the hydrogeological and geological studies act up on very significant role abouth urbanization, industry and landfill site selections. The main goal of this study is to investigate the water quality and to establish an interaction between abandoned disposal site and groundwater. The other main objective is to select a new landfill site in Torbalı Plain. Domestic and industrial solid wastes of Torbalı population center are dumped in to the Fetrek River without any protection. The geological and hydrogeological investigations of the region were performed to determine the contamination of the drinking water due to unplaned deposition of the solid wastes and discharge of the fluid waste without any protection. According to the detailed investigations of the region, these disposal areas are most important alluvium aquifer for the obtaining drinking water and located 30-35 m of depth below the groundwater level. Existing the waste disposal site is used as dumping area. This dumping area has not covered by clay liner and no any gas drainage system and also leachate control system. Therefore, mainly water runoff and leakage create the significant groundwater pollution.VI During the investigation of the groundwater contamination of the unplanned disposal site and Fetrek River, the systematic water samples are collected and then analysed. According to these analysis, the contamination of the groundwater is accepted at normal standard level in the case of drinking water. By using obtained contamination parameters, the map of the pollution and vulnarability risk is prepared. According to hydrogeological studies, the Saibler clay mines and its surrounding areas have limited groundwater amd impermeable characteristic, while other litological units having permeable and unconfined aquifer characteristics(karstic aquifer, alluvium aquifer and low permeable schist aquifer/aquitard). Therfore, these geological units are accepted as productive areas and not to use as landfill areas. The Neogene claystone is accepted an impermeable rock unit with 300 m of thickness. During the drilling activities, some permeability tests are performed from different depth of the Neogene claystone profile. As a result., 10"10 permeability values are obtained, therefore, this unit is accepted as impermeable unit. Also, the Neogene claystone is accepted as a aquitard unit without groundwater. According to the hydrogeolgical parameters, it is concluded that this impermeable unit is suitable for landfill area. The new landfill area will be plan establised until 2030. The new landfill site will be consisted natural clay liner for leakage storage. If drainage of water and its deposition, gas discharge system, rain and surface water drainage system, and surface cover are considered well, the contamination of the groundwater of the Torbalı Plain will be procteced. Immediately, the chemical and biological refined system for the solid waste, seewage and leakage should be established at the Torbalı Plain. Finally, these refined waste waters should be used for agricultural purposes.