Akira Koizumi*, Toyono Inakazu*, Kenji Ogura*, Shiro Kawaguchi* and Shigehisa Tazaki**

( *Tokyo Metropolitan University, **Nihon Jogesuidou Ltd. )

Abstract

The regional waste treatment planning is needed in many areas where it is difficult to treat wastes effectively and economically, and to find suitable disposal sites by themselves. This planning in which several municipalities cooperate with each other to treat their wastes, is a good solution for regions. At this moment, it is the problem how to decide the boundary of planning area. There are so many evaluation factors; historical, geographical, social, economical, and political factors, in deciding the size of area-wide, however it is difficult to consider all of them. We propose a method to evaluate the distance between each area, and to make a cluster according to the length, that is, the two closest areas are connected at first. Then all areas are connected with each other in turn by the length of two areas. And we show in a case study, how to decide the most economical boundary of planning area by evaluating treatment and transport costs.

Key words: regional waste treatment, area-wide, cluster analysis