Leak Detection in Water Wells using Hydrogen Tracer Gas

Abstract

The detection of leaks in construction components of wells in the unsaturated zone is difficult. An economic and technically simple method for direct detection and tracing the pathways of infiltration water in the unsaturated zone does not exist so far. The tracer gas method is designed for the detection of preferential water pathways in the unsaturated or saturated zone and is used to check the tightness of the construction of the well above the water table. Physical basis of this method is the utilization of the density difference between the soil air and the tracer gas pressed into the well tube or in a drainage pipe of a spring. The tracer gas in the ground air can escape and ascend to the surface of the ground through leakages in den construction. It uses the cavity and pore systems that can also be used by microbiologically contaminated infiltration water. The areas with positive tracer signals pose a higher microbiological risk potential and must be included into restoration and rehabilitation planning.