Method and system to locate leaks in subsurface containment structures using tracer gases

摘要

The present invention integrates an inverse modelling technique and a field measurement system. The system uses inexpensive and non-hazardous gaseous tracers injected inside the contained volume of a subsurface barrier or geomembrane to quantify the location and size of any leaks in the barrier. The vapor sampling point installation, which allows the collection of soil gas samples from multiple points (#1 - #12) around the outside surface of barrier installation, can be accomplished with conventional rotational drilling, direct push or sonic emplacement technologies. The system uses a field-proven soil gas analyzer for evaluating composition of such collected vapor samples and indicating penetration of tracer gas past the barrier, incorporated in a sampling system capable of monitoring many sample points with relatively high time resolution. A rigorous numerical inverse modelling technology, as used with or without non-linear global optimization and simulated annealing, is integrated with the data system for real time analysis.