Biosolids Beneficial Use Program

New York City’s Biosolids Program is Coming Up Green

What are Biosolids?

...solid organic matter recovered from the sewage treatment process and used especially as fertilizer.

...Webster’s 1999 Collegiate Dictionary

New York City produces approximately 1,200 tons of biosolids every day. In 1988, ocean disposal of biosolids was banned by the federal government and New York City was required to find alternative land-based use for this material. Recognizing the value of biosolids, the New York City Department of Environmental Protection (DEP) implemented a program to beneficially use biosolids. Today, the City’s biosolids are used to fertilize crops, and improve soil conditions for plant growth.

This chart shows how New York City biosolids are currently managed. The City can adjust its commitment to each of the beneficial uses depending on current economic conditions.

Biosolids Facts

• Biosolids and products derived from biosolids are valuable resources, rich in nutrients essential to plant growth.

• Based on scientific research, biosolids are safe when used according to regulations.

• The use of biosolids products reduces agricultural use of chemical fertilizers.

• Application of biosolids increases soil productivity by improving soil texture, stimulating root growth and increasing water-holding capacity.

• Plants grown in soils where biosolids have been applied are more resistant to disease and drought conditions.

Beneficial Use

The management of biosolids in a manner to recover the resource value.

How are New York City’s Biosolids Prepared for Beneficial Use?

New York City’s biosolids are managed by companies that have been awarded long-term contracts. Through the following processes these companies can either land apply biosolids or convert them into products such as compost, liming agents or pellets:

• Land Application: Biosolids are spread on land to return nutrients to the soil. Biosolids are spread less than a quarter inch thick and sometimes are plowed into the soil. In Texas, New York City’s biosolids are applied to rangeland to improve soil.

• Drying: Biosolids are heated to dry the material. Fertilizer pellets are formed during the process. These pellets can be used directly on the land or mixed with other materials to make special fertilizer blends. New York City’s biosolids are made into pellets at a facility in the Bronx. The pellets are sold across the country. Many of them are used on citrus groves in Florida.

• Composting: Biosolids are mixed with a bulking agent, such as wood chips. The bulking agent allows more oxygen to penetrate the mixture, providing an ideal environment for decomposition of the biosolids. The resulting product, compost, is similar to peat moss and used as mulch or soil conditioner at golf courses, nurseries, home gardens, lawns, etc. New York City’s biosolids are being composted at a facility in Pennsylvania.

• Alkaline Stabilization: Biosolids are mixed with a highly alkaline material, such as lime or Portland cement. This process results in a product which resembles soil and is used as an agricultural liming agent. New York City’s biosolids are alkaline stabilized at a facility in New Jersey. All of these processes destroy disease causing organisms and reduce moisture content, resulting in products that are easy to handle and have characteristics similar to many agricultural products.

Industry Contacts

If you have questions or would like more information about DEP’s biosolids management program, please contact:

The DEP Help Center
59-17 Junction Boulevard
Corona, NY 11368
718-DEP-HELP (337-4357)

More detailed information on biosolids is also available from:

U.S. Environmental Protection Agency
Office of Water, Resource Center
401 M Street, SW (RC-4100)
Washington, DC 20460
(202) 260-7786
http://www.epa.gov/owm/bio.htm

Water Environment Federation
601 Wythe Street
Alexandria, Virginia 22314-1994
(800) 666-0206
http://www.wef.org
email questions to: techinq@wef.org