1992, uncontrolled landfills in Izmir were closed on the ground that they threat the public health and Harmandalı ý Hazardous Wastes Landfill Area has been put into service by Izmir Metropolitan Municipality. Harmandalı Region, which was selected as a sanitary landfill area, has an area of approximately 900 000 m2 and is located in the border of the city Izmir. Izmir is the third biggest city of Turkey with a population of 3.5 million. In this study, the probable impacts of Harmandalı Sanitary Landfill Area on groundwater quality have been investigated. In order to predict the effect land disposal site, “Computer Model of Two-Dimensional Solute Transport and Dispersion in Groundwater” has been applied to the Harmandalı area by using the available data. The results of the model have been controlled after eight years by groundwater analysis in the area.