Not all of these leak detection methods can be used for both tanks and piping. Leak detection methods for piping include groundwater monitoring, vapor monitoring, secondary containment with interstitial monitoring, and tightness testing. Pressurized piping must also have an automatic line leak detector. See later sections on suction and pressurized piping for full discussions of the requirements for piping. A brief description of leak detection methods appears on the next two pages.
More complete descriptions appear in the following sections.
Groundwater Monitoring Groundwater monitoring senses the presence of liquid product floating on the ground water. This method requires installation of monitoring wells at strategic locations in the ground near the tank and along the piping runs. To discover if leaked product has reached ground water, these wells can be checked periodically by hand or continuously with permanently installed equipment. This method cannot be used at sites where ground water is more than 20 feet below the surface. This method requires installation of carefully placed monitoring wells.