Solid wastes that are residuals of production and consumption have steadily increased in quantity in recent years. Historically, many of these residuals have been discarded into the environment which appeared to have the capacity to handle them. However, now it is widely believed that these residuals are responsible for the degradation of environment quality by increasing air, water, and land pollution. Ecological considerations have increased the complexity of handling solid wastes and have stimulated the need for alternative methods of managing various types of wastes.

Local and municipal authorities and private industry provide waste collection and disposal services. Municipal services are generally financed out of taxation revenues, so it is in the public's interest to have an efficient, cost-minimizing operation at some publicly acceptable standard of quality of service.