What is the required leak detection rate from any portion of the tank during tank tightness testing?

The required leak detection rate during tank tightness testing is crucial for ensuring the environmental safety and integrity of underground storage tanks (USTs). A detection rate of 0.1 gallons per hour is the standard used in these tests. This value is based on guidelines designed to identify small leaks that could lead to significant environmental contamination over time if left unchecked.

By having a detection threshold set at this level, operators can identify and address potential leaks before they escalate into more serious problems, protecting groundwater and reducing the risk of regulatory non-compliance. This standard reflects the balance between practical detectability and the need for stringent safeguards against leaks that could have widespread ecological impacts.

The other rates would not be suitable for early detection of small leaks; they either represent higher thresholds that could allow for more significant unnoticed leakage or are unrealistic for the sensitivity needed in environmental monitoring.