Biosolids

Biosolids, also referred to as sewage sludge, are the solid or semi-solid organic materials resulting from wastewater treatment. After processing, the liquid effluent is discharged to nearby waterways and the biosolids are either disposed of through landfilling, incineration, long-term storage, or deemed safe for ‘beneficial use’.

Approximately, 16% of biosolids produced annually in New York State qualify as beneficial use with roughly 12,888 dry tons (<5%) land applied across about 30,000 permitted acres (NYSDEC, 2018). 

‘Beneficial use’ includes application to agricultural lands as the biosolids provide soil benefits through nutrient, lime, and organic matter additions, while offsetting input costs for farmers and disposal expenses for municipalities. However, the standard for safety only includes pathogen level reductions and regulatory thresholds for some toxic metal contaminants. No safety thresholds exist for emerging pollutants or persistent organic contaminants coming from per- and polyfluoroalkyl substances (PFAS) compounds, microplastics, and other substances that are known to be found in biosolids and detrimental to environmental and human health.

"The Case for Caution"

• A Brief Summary of the Federal Standards for Land Application of Sewage Sludges. 3p summary of the US EPA Part 503 rules, 1997.
• Comments on Proposed US EPA Standards for Dioxins in Land Applied Sludge. 7p critique by 7 Cornell faculty, 2000.
• Proposed Revisions to Part 360 Rules. 12p comments by 6 Cornell faculty on NYS Department of Environmental Conservation rules pertaining to land application of sewage sludges, 2002.
• Review of Risk Assessment for Dioxin in Land Applied Sludges. 8p comments on US EPA risk assessment, 1999.
• Recommendations for Municipal Sludge Ordinance/Rules. 8p information to assist in drafting municipal rules restricting land application of sewage sludges, 2003.
• The Role of Municipalities in Regulating the Land Application of Sewage Sludge and Septage. 66p article published in the Natural Resources Journal 41(1):77-123, 2001.
• The Significance of the Recent Virginia Supreme Court Decision on Local Ordinances Regulating Land Application of Sewage Sludges. 1p discussion, 2001.

National Academy of Sciences Review

• Biosolids Applied to Land: Advancing Standards and Practices (National Research Councl). Press release. 2002.
• "Comments on" Standards for the Use of Disposal of Sewage Sludge: Agency Response to the NRC Report on Biosolids Applied to Land and the Results of EPA's Review of Existing Sewage Sludge Regulations, 26p comments on the plan of US EPA to respond to the recommendations of the NRC report. These comments appear in the Federal Register 68:17379-17395, 2003.
• Land Application of Sewage Sludges (aka Biosolids): The Case for Caution. 29 slide Powerpoint presentation to the NRC, 2001.

Northeast Research Committee on Land Application

• Guidelines for Application of Sewage Biosolids to Agricultural Lands in the Northeastern U.S. 36p recommendations developed by 9 scientists from 5 universities, 2007.
• Members and Affiliates of the Northeast Regional Committee on Land Application of Sewage Biosolids.
• Northeast Regional Committee on Land Application of Sewage Biosolids: Committee Reports. Minutes 2004, Annual Report 2004, Annual Report 2003, Annual Report 2002.
• Research publications of the Northeast Regional committee on Land Application of Sewage Biosolids. 6p list of references.
• Research Project Proposal of the Northeast Regional Committee on Land Application of Sewage Biosolids. 5p document.

Risk analysis and research

• Case for Caution Revisited: Health and Environmental Impacts of Application of Sewage Sludges to Agricultural Land. 25p document containing new findings regarding the environmental and health implications of sewage biosolids applied to agricultural soils. 2008.
• Comments on Proposed EPA Standards for Dioxins in Land Applied Sludge. 7p critique by 7 Cornell faculty, 2000.
• Land Application of Sewage Sludge: An Appraisal of the US Regulations (The Case for Caution). Article critiquing the US EPA risk assessment on which the federal Part 503 rules pertaining to land application of sludges are based. Published in the Int. J. Environment and Pollution 11(1):1-37, 1999.
• Organic Chemicals in Sewage Sludges. Article reviewing the presence and significance of organic chemicals in sewage sludges. Published in the Science of the Total Environment 367(2-3):481-497, 2006.
• Review of Risk Assessment for Dioxin in Land Applied Sludges. 8p comments on US EPA risk assessment, 1999.
• Scientific Papers on Sludge by Cornell Faculty. Links to abstracts and articles.
• Septage Quality and its Effect on Field Life for Land Applications. Article on limits to land application due to metals in septage (septic tank pumpings). Published in the Journal of the American Water Resources Association 39:87-97, 2003.
• Targeted National Sewage Sludge Survey Report, from EPA on contaminant concentrations on sewage sludge. 2009.

Use and guidelines

• Considerations for Dairy Farms Regarding Use of Sewage Sludges, Sludge Products and Septage. 23p report and 6p summary of a document by 7 Cornell faculty and Extension educators, 2003.
• Guidelines for Application of Sewage Biosolids to Agricultural Lands in the Northeastern U.S. 36p recommendations developed by 9 scientists from 5 universities, 2007.
• Home Garden Use of Milorganite®. 2p fact sheet addressing questions about use of this dried sewage sludge product in the home garden. 2006.
• Using Organic Matter in the Garden. Pages 16-26. Chapter on use of various soil amendments including manure, sewage sludge and compost 2000.