Abstract: Methods and systems are provided for monitoring a tracer within a monitored system that includes at least three barrier layers and at least three corresponding tracers. The barrier layers—referred to as a first, second, and third barrier layer—may each have an initial association with a different one of the three tracers. The methods and systems may further enable detection, such as after the monitoring step, of a tracer at a location outside its initial associated barrier layer, where the detected tracer may be one of the three tracers. In certain embodiments, additional barrier layers and/or additional tracers may be employed, and interactions between and/or among them may allow determination of the location, concentration, amount, and identity of one or more traced compositions, including, for example, identification of breaches, within sealable monitored systems.

Abstract: The invention provides a tracer release system for releasing tracer into a well. The tracer release system comprises at least one tracer release apparatus. The apparatus comprises at least one tracer source reservoir comprising at least one tracer, at least one injection port configured to be in fluid communication with the well; and at least one controllable valve located between the at least one tracer source reservoir and the at least one injection port. The at least one controllable valve is configured to control an even release of the at least one tracer into the well for a desired duration and/or frequency.