Which of the following is not a required determination for surface water treatment facilities?

Fluoride is not a required determination for surface water treatment facilities. While monitoring for fluoride can be important in certain contexts—such as when considering the health benefits for dental hygiene—it is not a standard regulatory requirement for the treatment of surface water.

In contrast, the other determinations play crucial roles in ensuring water quality and safety. The jar test is an essential procedure for assessing the effectiveness of coagulation and flocculation in water treatment processes, informing operators on how best to optimize these stages for effective particle removal. Turbidity measurements are critical for assessing water clarity and detecting the presence of suspended solids, which can indicate contamination. Disinfectant residual is vital for ensuring that the water remains safe as it travels through the distribution system, as it verifies the effectiveness of the disinfection process. Each of these parameters is critical for maintaining public health and compliance with regulatory standards in water treatment.