Wastewater Treatment Operator Certification Practice Test

What is the primary purpose of using chlorine in wastewater treatment?

1. To adjust pH levels

2. To neutralize odors

3. To kill harmful microorganisms

4. To enhance sludge settling

The correct answer is: To kill harmful microorganisms

The primary purpose of using chlorine in wastewater treatment is to kill harmful microorganisms. Chlorination is a critical process used to disinfect treated water, ensuring that pathogens such as bacteria, viruses, and parasites are effectively eliminated before the water is discharged into the environment or reused. This disinfection step is crucial for protecting public health and preventing waterborne diseases. While adjusting pH levels, neutralizing odors, and enhancing sludge settling are important aspects of wastewater treatment, they are not the primary reasons for chlorine's use. Chlorination specifically targets microorganisms, making it an essential step in the treatment process to achieve safe and clean wastewater that meets regulatory standards.