FOOD WASTE INCLUDES uneaten portions of meals and trimmings from food preparation activities in kitchens, restaurants and cafeterias. Food waste is the third-largest component of generated waste by weight. However, because of its low composting rate, food waste is the largest component of discarded waste by weight.

According to a study by the University of Arizona Garbage Project, Americans throw away 1.3 pounds of food every day, or 474.5 pounds per year. This is more than twice the U.S. Environmental Protection Agency's (EPA) estimates. In response to this and a previous U.S. Department of Agriculture (USDA) study, the EPA has revised its data methodology from the late '90s to present. Increased consumption of packaged foods was a key factor causing food waste's share of the solid waste stream to decrease by one-sixth in the period from 1960 to 2000.

The USDA estimates that higher percentages of fresh fruits and vegetables, dairy and grain products are thrown away, while lower percentages of meat, dried beans, nuts and processed foods are disposed of.

Food waste composting is in its infancy, held back by cost and vector control concerns.

Chaz Miller is state programs director for the Environmental Industry Associations, Washington, D.C. E-mail the author at: cmiller@envasns.org.

Food Waste Municipal Solid Waste (MSW) Facts:

Generated:

• 26.2 million tons or 11.4% by weight.*
• 183.9 pounds per person.*

Composted:

• 730,000 tons, a 2.8% recovery rate.*
• Organic and highly compostable.
• Grocery store food processing trimmings are a prime resource for composting facilities.
• 350 food waste composting sites in 2000, mostly at institutions such as prisoners or colleges. A small number were offsite composting facilities, usually with yearly throughputs from 5 tons to 100 tons.
• New Jersey and Minnesota lead in food composting.
• Composting is the controlled decomposition of organic matter by microorganisms into a humus-like product by generating heat and energy to destroy weeds, plants and human pathogens.
• Backyard compost piles with food wastes must be tightly controlled to eliminate pests.

Composting Cost:

Tipping fees are usually charged for incoming food waste.

Incinerated or Landfilled:

• 25.4 million tons or 15.8% of discarded MSW by weight.*
• Usually the wettest component of MSW with moisture content of 70% and Btu value one-third of MSW

Landfill Volume:

• 21.4 million cubic yards or 5.3% of landfilled MSW.*
• Food waste can decompose into methane in a landfill

Density:

• Landfilled food waste weighs 2,000 pounds per cubic yard.
• Food scraps, solid and liquid fats weigh 412 pounds in a 55-gallon drum.

Source Reduction:

• Packaged foods create less waste.
• In-sink kitchen disposal units transfer disposal of food waste to the wastewater system.

End-Market Specifications:

Each facility has its own specifications. Nonorganic materials such as metals and plastic must be kept out.

Sources:

Biocycle Magazine. Web site: www.jgpress.com

Composting Council of Canada. Web site: www.compost.org

Cornell Waste Management Institute. Web site: www.cfe.cornell.edu/wmi

“Handbook of Solid Waste Management,” Kreith, 1994.

“Measurement Standards and Reporting Guidelines,” National Recycling Coalition, Alexandria, Va., 1990. Website: www.nrc-recycle.org

“Municipal Solid Waste In the United States: 2001 Facts and Figures,” U.S. EPA, 2001. Website: www.epa.gov.osw

U.S. Composting Council. Web site: www.compostingcouncil.org.

*2001 EPA estimates.