Abstract
In order to carry out a precise water-purity control regarding pesticides, it is essential to judge the pesticides runoff situation of the river basin. In this paper, we modeled a mechanism of pesticide runoff by using level Ⅱ fugacity model in order to decide the priority of runoff pesticides on each basin, and constructed a method of calculating the index which indicated pesticide runoff potential on each period. We evaluated the pesticides runoff situation of Sagami-river and Sakawa-river in Kanagawa prefecture by using this method. As a result, estimated runoff volume of pesticides could be used as an index which indicated runoff potential, and RRI value which indicated runoff volume per ADI could be used as an index deciding the priority of runoff pesticides in detail.
