Action: Inspect overfill prevention equipment every 3 years. Tank Owner Responsibility: Maintain records demonstrating overfill functionality testing conducted within the last 3 years. Applies to all forms of overfill and documentation must be maintained for 3 years. This requirement applies to all new UST systems installed on or after October 13, 2018 and to all existing facilities beginning October 13, 2021. What is Overfill Protection? Overfill prevention devices are insta