Texas Commission on Environmental Quality (TCEQ) Class D Water Operator License Practice Exam 2025 - Free Water Operator License Practice Questions and Study Guide

In the context of returning a repaired main to service, maintaining a specific chlorine concentration is vital for ensuring the safety of the water supply. A concentration of 500 mg/L is typically required after repairs to effectively disinfect water systems. This level helps eliminate any pathogens that may have entered the distribution system during the repair process.

This high concentration is guided by regulatory standards, ensuring that any residual contamination is addressed before the water is deemed safe for consumption. Following a repair, it's crucial not just to disinfect but also to maintain this concentration for a specified duration to ensure thorough treatment of the water.

Once the disinfection period is complete and tests confirm the absence of harmful microorganisms, the concentration can be reduced, ensuring that the system is safe for reintroduction into the network. This process is essential in maintaining public health and compliance with safety regulations.