Impressed current cathodic protection systems must be inspected at least every how many days?

Impressed current cathodic protection systems are critical for preventing corrosion in underground storage tanks and associated piping systems. Regular inspections are essential to ensure these systems are functioning correctly and providing adequate protection.

The correct answer indicates that these systems must be inspected at least every 60 days. This frequency is established to ensure that any potential issues, such as power failures, equipment malfunctions, or changes in soil conditions that might affect the effectiveness of the cathodic protection, are identified and addressed promptly. Regular inspections help maintain the integrity of the system and protect the environment from leaks and spills associated with corrosion.

Each of the other options represents intervals that are either too short or too long. A 30-day inspection period may not be necessary since many systems can operate effectively for a longer duration without immediate issues. A 90-day inspection may allow for undetected problems to escalate, risking system failure. A 120-day interval could lead to significant risk over an extended period without oversight. The 60-day requirement strikes a balance between ensuring ongoing effectiveness and efficiency in monitoring system performance.