Using multi-criteria evaluation techniques of fuzzy analytic hierarchy process and fuzzy TOPSIS in locating waste sanitary landfill sites

Due to irregular and non-normative extension of cities, a lack of appropriate model for consumption and increasing growth of waste production, sanitary landfill is the most logical and economical method for municipal waste disposal. Due to the high sensitivity of the issue, detection of potential waste landfill sites requires comprehensive techniques. Therefore, this study aimed to select a suitable location for waste sanitary landfill of Shahriar by using multi-criteria evaluation techniques of fuzzy analytic hierarchy process and FTOPSIS (Fuzzy Technique for Order Preference by Similarity to Ideal Solution). First, the effective criteria for the selection of waste landfill were collected from the relevant organizations and they were analyzed and standardized by geographic information systems. Then, criteria weights were calculated by fuzzy analytic hierarchy process and after weights were applied in corresponding layers, layers were overlaid by fuzzy functions. Next, options were prioritized by FTOPSIS method. Thirty-one appropriate options were obtained by implementing above methods. Then prioritizing led to one option as the best site, which is located in the southwest of Shahriar. The results showed that selected options are located in a better site than the current landfill and this combined approach has a better performance than other methods because of considering the imprecise nature of phenomena.