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Bulk Products Requiring Site Permits
Class B biosolids products
These products are available only through contract with biosolids management companies or wastewater treatment facilities and require site permits from the state environmental agency prior to use. A farm nutrient management plan is encouraged, and required in some states (e.g. to comply with Maine’s nutrient management law). Class B biosolids must be applied at the agronomic rate, except in special land reclamation circumstances. Follow all regulations and agricultural best management practices, including buffer zones. In sensitive watersheds where phosphorus is a concern, application should be according to phosphorus needs (the same is true for manures and other fertilizers).
Ensure careful management of odors, if odors are possible. Some biosolids have minimal odor, others more. The manager of the biosolids program should know what potential for odors exist and how best to manage them. Odor concerns can be addressed by:
--immediate incorporation or injection of biosolids into soil when used for growing annual crops such as corn;
--application of biosolids during cool, less humid weather;
--maintaining setbacks from neighbors;
--communication with neighbors, ensuring them of temporary nature of odors, if any.
The National Institute for Occupational Safety and Health (NIOSH) has a booklet available that may be useful to those working with Class B biosolids. The booklet is called "Guidance For Controlling Potential Risks To Workers Exposed to Class B Biosolids" and can be read online and is available for free download at http://www.cdc.gov/niosh/docs/2002-149/2002-149.html. While there are few, if any, known cases of significant illnesses from managing Class B biosolids, it is important for workers to remember that these materials may contain viable pathogens (disease-causing organisms), just as manures do, and that personal hygiene is important--washing hands is a good idea! In addition, individuals with compromised immune systems or other special vulnerabilities to infection should use extra caution around biosolids, manures, and farm environments.
Lime-rich biosolids
(generally >80% calcium carbonate equivalence)
Such biosolids are often applied as a liming agent, according to recommendations for lime or calcium carbonate equivalence. Application of lime rich biosolids according to standard agronomic rates based on nitrogen (N) could result in an excess of calcium and high pH levels in the soil, resulting in a reduction in availability of plant nutrients.
Lime-stabilized biosolids
Also contains abundant lime, but not as much as above. Such biosolids are generally applied to both boost soil pH and provide organic nitrogen (4 - 12%), phosphorus (2 - 4%), and trace plant nutrients. Excellent for corn and grass hay production.
Anaerobically digested biosolids
Provide organic nitrogen, phosphorus, and trace plant nutrients. Neutral pH.
Excellent for corn and grass hay production.
Pulp & Paper Mill Residuals or Short Paper Fiber
These byproducts of the treatment of process wastewater at pulp and paper mills are rich in organic matter--mostly wood fibers--as well as clay and lime. The nutrient value can be low to moderate, depending on the wastewater treatment process. These residuals are available only through contract with a pulp or paper mill or their independent contractor. Excellent for use in landfill caps and land reclamation projects where an abundance of organic matter is needed to build a topsoil layer. See Pulp and Paper Mill Residuals.
Septage
Septage from home septic tanks is used as a soil amendment and fertilizer for hay and corn crops by some farmers and has been for decades. Pathogen treatment, usually using lime to raise the pH, must be done prior to land application of septage. State regulatory programs govern the land application of septage; contact your state environmental agency’s water or wastewater division for further information.
Guidance to Farmers Using Biosolids
For specific state and regional regulations, contact your state environmental agency. See Resources.
Agronomic Rate
New England states have different requirements for agronomic rate calculations; contact your state environmental agency for details.
Agricultural Best Management Practices
A training module on general agricultural best management practices that can help control environmental impacts of farming practices, including biosolids use, can be found at http://www.epa.gov/watertrain/agmodule
Contact your local Cooperative Extension office, or the Natural Resource Conservation Service.
The 2000 EPA/USDA "Guide to Field Storage of Biosolids" is an excellent resource, providing up-to-date advice on managing bulk biosolids. Chapters address odors, water quality protection, pathogen questions, and best agricultural management practices for siting and providing buffers around biosolids stockpiles. A pdf copy can be downloaded from the EPA Biosolids website: http://www.epa.gov/owm/mtb/biosolids/index.htm
A useful 1998 guidance document for safely using manures and biosolids is available from the U. S. Food and Drug Administration, U.S. Department of Agriculture, and Centers for Disease Control and Prevention:
"Guidance for Industry: Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables."
Copies are available from: Food Safety Initiative Staff, HFS-32, U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, 200 C Street S.W., Washington, DC 20204, (Tel) 202-260-8920, (Internet) http://www.fda.gov
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