The dipole method (Electrical Leak Location) has been used on various types of civil engineering works in the last 20 years. The principle is well known and in good conditions it can detect pin hole faults in geomembrane materials and defects in extrusion seams. In the first part of this paper, the basic principles of the dipole method will be introduced. In the second part, two case studies of dipole leak locations will be presented. The first of these studies describes a multi-layered, 122,000 m2 mine capping project, the design of which was made to accommodate dipole leak location methods in terms of electrical isolation, thickness of material layers, and surface watering. The second case study describes a pulp mill landfill project that encountered contingencies during construction leading to changes in the project’s overall design. Dipole surveys for both of these projects underwent significant adjustments to adapt to project conditions, but in the second case study the geomembrane had suffered damage to the extent that a new dipole leak location protocol was required in order to ensure that acceptable quality standards were met. The goal of this paper is to educate engineers and leak location practitioners and to share valuable data about the dipole leak location method. This paper will also highlight the importance of including leak location in civil engineering projects early in the design stage, in order to prevent contingencies from negatively effecting survey performance and to ensure reliable survey results.
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