Abstract
Although there has been an increase in the national recycling rate for municipal waste since the year 2000, it has now reached a saturation point. One of the reasons behind this is the existence of uncaptured municipal waste flows, which skip over municipality treatment and recycling routes. This article discusses methodologies for estimating such flows and proposes ones that are more appropriate. Further, the paper presents the application of these methodologies in a case study from Shiga Prefecture, where a recycling rate that takes into account the uncaptured flows (true recycling rate) has been estimated. Specifically, estimation methodologies for collection of recyclables at stores, collection of recyclables by recycling companies, and for mixtures of municipal waste into industrial waste are discussed. The application of these methodologies in Shiga Prefecture shows that the amount of uncaptured recycling was estimated to be about a half the total recycling amount. Moreover, even though the true recycling rate was estimated to be about 13% greater than the current recycling rate, the trends in current and true recycling rates were actually not so different. This indicates that, for Shiga Prefecture, the existence of such uncaptured flows for municipal waste is having little influence on the saturated recycling rate.
