What is biosolids?

Biosolids refer to the primarily organic solid byproducts that emerge from the treatment of wastewater. During the wastewater treatment process, organic matter, nutrients, and pathogens present in the sewage are broken down. The treated sludge that remains, known as biosolids, is rich in nutrients and is often used as fertilizer or soil amendment in agricultural practices.

This definition highlights the importance of biosolids in recycling nutrients back into the soil, promoting sustainable agriculture, and reducing the volume of waste sent to landfills. Biosolids have been treated to meet specific standards for safety and quality, ensuring they can be reused beneficially.

In contrast, the other options provided do not accurately describe biosolids. Solid waste from landfills and inorganic waste do not relate to the biological treatment processes that produce biosolids. Untreated wastewater sludge lacks the necessary treatment to meet safety standards for use in agriculture. Therefore, option B distinctly captures the essence of what biosolids are within the context of wastewater treatment.