For existing USTs using automatic tank gauges, what is the minimum release detection capability that must be met?

The minimum release detection capability for existing underground storage tanks (USTs) utilizing automatic tank gauging systems is 0.2 gallons per hour (gph). This standard is in place to ensure that USTs have adequate monitoring systems that can detect leaks at a level that minimizes the risk of environmental contamination and complies with regulatory requirements.

Automatic tank gauges operate by continuously monitoring the volume of fuel in the tank and comparing it to the expected levels based on dispensing activity and is designed to detect even small leaks. By setting the minimum detection capability at 0.2 gph, regulatory authorities aim to strike a balance between practical monitoring abilities and the reduction of pollution risks. This threshold is considered adequate for alerting operators to potential leaks before they can lead to significant environmental harm.

The other options suggest higher detection capabilities, but the established standard specifically identifies 0.2 gph as the minimum necessary for effective release detection in order to manage potential environmental threats and ensure compliance with regulations.