Cost-Effective Solid-Waste Characterization Methodology

Characterization of municipal and county solid wastes as well as projection of waste-generation and -disposal rates are needed to plan and implement disposal and recycling activities. A literature review of solid-waste characterization studies revealed that conventional sorting methods are expensive and yield data with great variability. The results of such characterization studies for metropolitan regions have large standard errors, and individual results often fall within the error bounds of reported national average values. An alternative and more cost-effective methodology for estimating county- and city-level solid-waste composition and generation is proposed. The method is based on converting economic sales data for a metropolitan region into estimates of kilograms of solid waste generated. Prototype conversion factors were derived using a material balance approach. The methodology was calibrated using King County, Wash., data and validated on two adjacent counties. The results are promising enough that the methodology should be tested in other parts of the nation. The cost to apply this methodology is a small fraction of the cost of conventional sorting methods, and comparable estimates of major solid-waste components may be possible.