What is the required effluent pH range?

The required effluent pH range is critical in wastewater treatment as it influences various chemical and biological processes. A pH range of 6.0 to 9.0 standard units (s.u.) is considered acceptable for effluent because it ensures that the treated wastewater is not overly acidic or alkaline. This pH range is vital for protecting aquatic life and maintaining the health of receiving water bodies, as many organisms operate best within this range.

A pH below 6.0 could potentially harm aquatic ecosystems, while a pH above 9.0 might lead to issues such as ammonia toxicity in aquatic environments. Therefore, the 6.0 to 9.0 pH range is designed to align with regulatory requirements and environmental protection standards, making it the most suitable choice among the provided options.