ABSTRACT
In developing the analytical framework, two issues are addressed, which are expressed briefly as follows: many decisions involve criteria and goals, many of which are conflicting with some quantitative and some qualitative. We called this type of decision-making as Multiple Criteria Decision-Making (MCDM). One of the methods employed to support MCDM is the AHP. In addition to MCDM, another key point is that groups must make decisions. It is known that group decision-making is a very important and powerful tool to accelerate the consensus of various opinions from experts, which are experienced in practices. In this section, the FDM was taken to synthesize their responses for the questionnaires. The FDM is a methodology in which subjective data of experts are transformed into quasi-objective data using the statistical analysis and fuzzy operations. The main advantages of FDM (Kaufmann and Gupta, 1988) are that it can reduce the numbers of surveys to save time and cost and it also includes the individual attributes of all experts. Thus that can effectively determine the weighting of each parameter with the variation of geological conditions based on only required two rounds of investigations and comprehensive discussions by a group of experts.
