MORE THAN A DECADE ago, the U.S. Environmental Protection Agency (EPA), Washington, D.C., developed the solid waste management hierarchy, which ranked the most preferable ways to address solid waste management. Source reduction or waste prevention, which includes reuse, was listed as the best approach to managing solid waste, followed by recycling. Wastes that cannot be prevented or recycled should be incinerated or landfilled according to proper federal and state regulations. The EPA did not distinguish between disposal methods (i.e. incineration and landfilling are considered equal).
According to the EPA's latest data, more than 55 million tons of municipal solid waste (MSW) were prevented from entering the wastestream (i.e. the top of the pyramid). The amount of waste reduced has steadily increased since 1992 when only 0.6 million tons were reduced or reused. Of the 55 million tons prevented in 2000, almost half (25 million tons) came from organic materials, particularly yard trimmings. The next largest components prevented were containers and packages (28%), followed by nondurable goods such as newspapers, clothing (17%), and durable goods such as appliances, furniture and tires (10%).
After source reduction, there are primarily three methods for managing MSW: recycling, incineration and landfilling. According to the EPA's most recent data (2001), 68 million tons (29.7%) were recycled and composted, 33.6 million tons (14.7%) were incinerated, and 127.6 million tons (55.7%) were landfilled
The amount and management of MSW has changed significantly since the EPA started collecting data. Only 88.1 million tons of MSW were generated in 1960. Of this amount, 5.6 million tons (6%) were recycled, 27 million tons (31%) were incinerated and 55.5 million tons (63%) were landfilled. None of the MSW generated in 1960 was composted. Both the recycling and composting rates continued to rise each year, with recycling rates increasing more than 800 percent and composting rates increasing approximately 300 percent. Incineration rates have remained relatively constant from 1960 to 2001, with 1980 representing the lowest year at 13.7 million tons. The amount of landfilled MSW increased from 55.5 million tons in 1960 to a high of 131.8 million tons in 1999. After 1999, the amount of landfilled MSW declined slightly to 127.6 in 2002.
It's difficult to tell what the numbers will show in another 10 years. In the meantime, however, the statistics point out areas of progress and areas for improvements.
Edward Repa is the director, environmental programs, at NSWMA. He can be reached at (800) 424-2869 or [email protected].