Rapid urbanization and physical development have produced a significant quantity of construction and demolition waste in Bonab, a city in northwest Iran. In order to achieve a high level of accuracy and minimize subjective bias, Catastrophe Theory (CT) principles were combined in the Geographical Information System (GIS) environment for identifying suitable locations for safe disposal of the waste. Site selection process for construction waste landfill (CWLF) in Bonab city, involved preparation and integration of 12 maps representing elevation, slope, geology, soil type, land use, vegetation, distance to population centers, valuable ecosystems, river, groundwater, and access to the main roadways with the CT to reduce uncertainty associated with subjective evaluations. Evaluation of relative importance of the variables showed that elevation, slope, distance to the city, vegetation cover, and distance to communication networks have greater importance in site selection for construction waste landfill. On the contrary, distance to the river, groundwater level, distance to villages, and valuable ecosystems have the least impact. Suitable areas were identified in parts of the north and west of the city. The identified sites have a gentle slope, low agricultural potential, good access to the communication networks, suitable distance to the city, and no limitations regarding the groundwater level, geological formations and vegetation cover.
