Which term refers to a primarily organic solid product produced by wastewater treatment processes that can be beneficially recycled?

• A. Biomass
• B. Blank
• C. Biosolids
• D. Buffer

Answer: (C)

Biosolids are the primarily organic solid byproduct of wastewater treatment that can be recycled for beneficial uses. After the treatment process, the solids are stabilized (through digestion, composting, or chemical methods) to reduce pathogens and make them safe for land application. Once stabilized and meeting regulatory standards, these biosolids can be used as a soil conditioner or fertilizer, returning nutrients to the environment rather than sending the material to landfill. This distinguishes biosolids from other terms: biomass generally refers to organic matter as a whole, often the living or recently living material, not the specifically processed solid product intended for recycling. A buffer is a chemical used to maintain pH and has nothing to do with the solid byproduct of treatment.