Detecting and locating leaks in liners e.g. for barriers in construction of landfills, surface impoundments etc. - placing electrodes in ground around periphery of facility, or in leak detection zone for collection of electrical resistivity data, then mapping resistivity distribution beneath containment liner

摘要

The method for detecting and locating leaks in a geo-membrane lined facility containing liquids, sludges, or soils, using an excitation of the mass (mise-a-la-masse) electrical resistivity technique and an electrode array, comprises placing a number of electrical potential sensing electrodes in soil located peripherally outside the lined facility. A first set of electrical potential measurements is made on combinations of the sensing electrodes using a first sensing electrode pair as a current injection pair and a second sensing electrode pair as an electrical potential measurement pair. An electrical resistivity distribution is mapped under the lined facility, and is derived from the first set of electrical potential measurements by performing a mathematical inversion on same. An electrical current is injected into the liquid, sludge, or solid using an injection electrode located within the lined facility and a sink electrode located in an area outside of the lined facility. A second set of electrical potential measurements is made on combinations or the sensing electrodes located peripherally outside the lined facility. The second set of electrical potential measurements is analysed using mathematical inversion techniques to locate the leaks in the lined facility. The leak position is located by determining the coordinates of an electrical current source pole that best fits the measured potentials with the constraints of the known or assumed resistivity distribution.