The electrical leak location method was used to locate leaks in the geomembrane liners of single-lined and double-lined landfills covered with a protective soil cover. The landfills ranged in size from 0.40 hectare (one-acre) to 3.2 hectares (eight-acre). Water in the leak detection system under the primary liner indicated the primary liners were leaking.
The principal of the electrical leak location method is to place a voltage across the geomembrane liner and then to detect areas where electrical current flows through leaks in the liner. The electrical leak location method proved to be a practical and efficient method to locate leaks under a protective soil cover. This method was very successful in locating leaks to solve the leak problems at the landfills.
Geomembrane liners are covered often with sand or soil to protect the liner from mechanical damage and damage from solar ultraviolet radiation. Geomembrane liners covered with soil materials are also used to cap landfills. Because the geomembrane liner may be damaged while emplacing the protective soil, an electrical leak location survey of the soil-covered geomembrane is a highly effective method for ensuring that leaks will be located in the liner. The method is particularly valid because the liner is tested under load, and after the liner has been exposed to possible damage.
The development of the electrical leak location method began in 1980 and commercial surveys have been available for the past seven years. Electrical leak location surveys with soil cover have been conducted commercially for the past five years. The commercial surveys have been overwhelmingly successful in that many leaks were efficiently and accurately located in installations that had been previously tested with other methods.