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.

Case for Caution Revisited: Health and Environmental Impacts of Application of Sewage Sludges to Agricultural Land (Harrison, E., and McBride, M, 2009)

• USEPA biosolids 
• USEPA laws and regulations of biosolids
• NYSDEC organics materials management - New York State laws on biosolids 

Risk analysis and research 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.
• 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.
• 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.