ABSTRACT
Approximately 7.2 million ton of biosolids (treated sewage sludge) were generated in the United States in 2004. Of that total, about 55% was eventually applied to soils for agronomic, silviculture, and/or land restoration purposes. Of the total applied to soils, 74% was used on farmland for agricultural purposes. Small percentages were used for land restoration and in silviculture. About 22% was treated and tested to meet the USEPA’s highest quality classification (Class A/EQ), and was publicly distributed for a variety of uses, including landscaping, horticul ture, and agriculture (NEBRA 2007). Recycling options are described in various documents (Crites and Tchobanoglous 1998; Crites et al. 2000; USEPA 1994a, 1995a,c; Water Environment Federation [WEF] 2012).
