In the United States, what percent of biosolids are beneficially used as a fertilizer on farmland following treatment?

• A. 60%
• B. 40%
• C. 20%
• D. 80%

Answer: (A)

The key idea is that many biosolids are treated not as waste to be disposed of, but as a resource that can improve agricultural soils. Once biosolids are stabilized and pathogen-reduced, they provide nutrients like nitrogen and phosphorus and add organic matter to farmland. In the United States, about 60% of biosolids are beneficially reused as fertilizer on farmland after treatment. This reflects the emphasis on turning waste into a useful product while meeting safety standards. The remaining biosolids are disposed of through other means such as landfilling or incineration, or diverted to non-agricultural uses. The 60% figure is the commonly cited measure of how much biosolids are land-applied, making it the best choice among the options.