Decision Criteria in Solid Waste Collection

Solid waste collection in residential and commercial areas requires numerous decisions by the crew or supervisor pertaining to collection areas, collection time, crew overtime, and truck routing. Using management problems frequently encountered in solid waste collection in Bangkok, Thailand, three decision criteria were developed using economic analyses: (1) Whether the collection crew should return to a collection area after the trip to the disposal site has been completed; (2) whether the crew should return to the same or a different collection site; and (3) whether to take overtime once the regular working day is finished and the truck is only partially filled. These criteria were quantified by optimizing the collection system operating cost curve and were incorporated into a simulation model of the entire system. The sensitivity of the decision criteria were tested with respect to the following variables: collection area, crew overtime, crew size, hauling distance, and truck size. Graphs were prepared for simple direct application of the criteria to every day problems encountered during collection of solid wastes.