What is TCEQ's requirement for plants with a capacity greater than 3 mgd?

For surface water treatment plants with a capacity greater than 3 million gallons per day (mgd), TCEQ mandates the installation of two clarifiers operating in parallel to ensure effective sedimentation and removal of particulates from the water. This requirement is crucial because parallel operation allows for consistent, reliable treatment even if one clarifier goes offline for maintenance or emergencies. It enhances the overall efficiency and reliability of the treatment process, ensuring that the plant can handle fluctuations in flow and maintain high water quality standards.

The necessity for two clarifiers is rooted in operational redundancy and the need to meet specific treatment goals mandated by TCEQ. This is essential in preventing overloading of individual clarifiers, which could lead to decreased performance and potential water quality issues.

The other options do not meet TCEQ's stringent operational standards for larger capacity plants. For instance, being exempt from providing clarifiers would compromise the fundamental principles of effective water treatment. Having only one clarifier fails to provide the necessary redundancy and could jeopardize system performance, while the requirement of installing additional filtration systems is not specifically mandated for plants strictly based on capacity but rather on the treatment process and desired outcomes.