Composting

Composting is a biological process during which naturally occurring microorganisms (e.g. bacteria and fungi), insects, snails, and earthworms break down organic materials (such as leaves, grass clippings, garden debris, and certain food wastes) into a soil-like material called compost. Composting is a form of recycling, a natural way of returning nutrients to the soil.

Yard trimmings and food wastes together make up about 24 percent of the waste stream in the United States. Nationwide, leaves and yard trimmings annually amount to about 56.2 million tons of waste. Yet, only 64 percent of yard trimmings and 2.6 percent of food wastes were composted in 2007. (Municipal Solid Waste in the United States: 2009 Facts and Figures)

Composting yard trimmings and food wastes can:

• Divert an average of 700 pounds of such material per household per year from the waste stream
• Reduce local garbage disposal costs
• Conserve valuable landfill space
• Reduce air emissions from the incinerator plants that burn garbage
• Produce a nutrient-rich additive for soil.

Composting helps the environment and is a convenient, beneficial, and inexpensive way to handle organic wastes.

In New England, several state agencies and other organizations offer information on composting programs not only for individual households, but for larger entities such as municipalities, food processors, restaurants, universities, and agricultural operations. A few examples of some local composting projects:

Massachusetts Supermarket Recycling Program Certification (SRPC)
The Massachusetts Department of Environmental Protection (MassDEP) and the Massachusetts Food Association (MFA), through a Memorandum of Understanding, have partnered to establish a voluntary Supermarket Recycling Program Certification that encourages supermarkets to develop sustainable programs for recycling and reusing organics and other materials. Participating stores not only save money, but also improve their compliance with existing Massachusetts waste disposal bans (rules that prohibit disposal of certain materials that can be recycled.

Bates College
At Bates College in Lewiston, Maine, pre-consumer kitchen residuals (e.g. unbleached napkins, coffee grinds, egg shells, fruit/vegetable peelings) are taken to a local farm for composting. The program saves Bates College in disposal costs and water usage (as less food waste is put through garbage disposals). For more information on this program:

• Best Management Practices for Colleges and Universities, US EPA New England, Case Study: Dining Services, Composting Program, Bates College, January 2007 (PDF) (5 pp, 87K, about PDF)

Dartmouth/Hanover Compost Facility (DHCF)
A public/private partnership formed in 1998 to compost food wastes. For more information on this program:

• Dartmouth to manage composting facility, VOX, the Newspaper for Dartmouth Faculty and Staff, May 3, 2004

Northampton and Amherst, Massachusetts
Two municipalities developing a system for restaurant and school food waste composting. For more information:

• Composting in Restaurants and Schools – A Municipal Toolkit, May 2003, Center for Ecological Technology (PDF) (68 pp, 2.2MB, about PDF)

For more information about New England contacts and programs, see State Agencies and Other Organizations.

For more information on composting, visit EPA's national Composting web site.