【Paper】
Geographical Analysis of Imbalances between Discharge Amounts and Treatment Capacities for Demolition and Construction Wastes
Takatsune Kawahata*, Masahiro Osako*, Masato Yamada*
Tomohiro Tasaki*, Yasuhiro Matsui** and Koichi Tachio***
* Research Center for Material Cycles and Waste Management,
National Institute for Environmental Studies
** The Graduate School of Natural Science and Technology,Okayama University
*** Japan Environmental Sanitation Center
† Correspondence should be addressed to Takatsune Kawahata:
Research Center for Material Cycles and Waste Management,
National Institute for Environmental Studies
（16-2 Onogawa, Tsukuba, Ibaraki, 305-8506 Japan）

Abstract
Understanding of the inefficiency of waste transportation is needed in order to take substantial measures necessary to establish material recovery systems for demolition and construction wastes over a wide area. We made a flow model that can estimate flows of such wastes between cities and towns. This model uses an algorithm based on the assumption that waste flow is controlled by spatial distribution factors, including the amount of waste discharged, the intermediate treatment capacity and the road distance between two points in the Kanto region. In addition, we developed spatial and quantitative indicators of regional waste imbalances caused by facility distribution. We suggest ways to apply these indicators to decision-making processes from the perspectives of material recovery promotion and improper waste disposal prevention.

Key words: demolition and construction wastes, flow model, imbalance indicator, waste facility siting, geographical distribution