If a tank integrity test is required, what size release must it be capable of detecting?

The correct choice is based on regulatory guidelines that specify the performance requirements for tank integrity testing. A tank integrity test must be capable of detecting a release size as small as 0.1 gallons per hour (gph). This threshold is significant because it ensures that even small leaks, which can accumulate over time and lead to environmental contamination, are detected promptly. The detection of a release at this rate allows for early intervention to prevent potential damage to the surrounding environment and to maintain compliance with environmental regulations.

The other sizes, while they might be relevant in different contexts, do not meet the stringent detection standards set for tank integrity testing. Therefore, the choice of 0.1 gph accurately reflects the necessary sensitivity of the testing methodology in practice.