Solid Waste Management: Spotlight on Best Practices
EM—Highlighting the “waste” side of the Air & Waste Management Association (A&WMA), the March issue provides insights on waste-themed issues ranging from waste prevention to more sustainable landfill design and operations.by David Minott
“Waste Not, Want Not!” Its intended meaning? If you don't waste your resources, you are more likely to always have enough. This venerable maxim, dating from the 1700s, reflects ageless wisdom that remains embedded today in the resource conservation component of sustainability concepts.
Regarding solid waste management today, just how much waste do we generate and what is its fate? According to the U.S. Environmental Protection Agency (EPA), the waste generation rate in the United States presently stands at more than 3/4 ton per person per year. What becomes of all the waste we generate? In the United States, just over one-third is recycled or composted; approximately 10–15 percent is post-recycling waste that is presently converted to energy; and the remaining fraction, about 50 percent, is disposed in landfills.
Sustainable waste management is often illustrated as a pyramid, depicting a preferred hierarchy of waste management methods. At the top of the pyramid, as most preferred, is to minimize the generation of waste in the first place. Examples include reducing packaging, reusing materials that would normally be discarded, and diverting food waste to homeless shelters instead of discarding. After reducing waste generation, the next-down preference in the hierarchy entails recycling and composting of waste to reduce disposal and reclaim useful materials. Following recycling in the preference pyramid is the recovery of energy from post-recycling waste, via combustion, gasification, or anaerobic digestion.
In total, about one-half of the waste generated in the United States is currently diverted from disposal via reuse, recycling, and energy recovery. While this is a significant fraction, the flipside is that the remaining 50 percent is post-recycling waste that must be disposed, principally via landfilling. This means that landfills remain an essential and fundamental underpinning for the pyramid. While landfill disposal occupies the bottom of the preference pyramid, landfill professionals continue to make effective progress in advancing sustainable design and operating practices in order to increase landfill safety, minimize pollution migration into the environment, and recover energy from landfilled waste.