What methods are commonly used for release detection?

The correct answer is based on the standard practices established for underground storage tank (UST) release detection. Inventory control, automatic tank gauging, and interstitial monitoring are recognized and commonly employed methods that help in identifying any leakage or release of hazardous substances from USTs.

Inventory control involves maintaining a regular log of the volume of fuel entering and leaving the tank, which helps detect discrepancies that could indicate a leak. Automatic tank gauging utilizes advanced technology to measure the liquid levels in the tanks continuously and can raise alerts if unusual patterns or changes are detected. Interstitial monitoring is a method that evaluates the space between the tank and its secondary containment, allowing for early detection of leaks that might not yet have reached the environment.

In contrast, other methods such as radio signals and GPS tracking, while useful for tank location and management, are not reliable for detecting releases. Water quality testing and air sampling, on the other hand, are typically conducted more as assessments of environmental contamination rather than direct daily monitoring of tank integrity. Visual inspections alone do not provide sufficient reliability to detect all potential leaks, as they can miss subtle but significant signs of a release. Thus, B clearly represents the most effective and widely accepted methods for release detection in UST systems.