A new approach for siting landfills using fuzzy sets

Current landfill siting practice is based on the simple process of elimination. Starting from a region, such as a state or a country, one identifies tracts of undeveloped lands that are large enough for the proposed landfill development. Thereafter, the selection process eliminates or screens out those sites that are prohibited by the applicable law for landfill development. This process subsequently generates a number of candidate sites which may have different impacts on the environmental, economic, and political aspects of landfill site selection. There is, however, little effective, efficient guidance on how to pursue this siting process further. This paper documents the development of a new approach for siting landfills. The new approach takes the advantages of fuzzy set theory in formulating a procedure for systematic evaluation and ranking of prospective sites based on subjective and ambiguous data. A conceptual model for landfill siting is presented, followed by discussions of various aspects of the model, including establishment of the evaluation tree, determination of weights and relative scores, and the overall assessment and ranking. Results of this study shows that the developed model is an effective tool for siting landfills.