ASTM D7703-11

Geomembranes are used as barriers to prevent liquids from leaking from landfills, ponds, and other containments. For this purpose, it is desirable that the geomembrane have as little leakage as practical.

The liquids may contain contaminants that if released can cause damage to the environment. Leaking liquids can erode the subgrade, causing further damage. Leakage can result in product loss or otherwise prevent the installation from performing its intended containment purpose.

Geomembranes are often assembled in the field, either by unrolling and welding panels of the geomembrane material together in the field, or unfolding flexible geomembranes in the field.

Geomembrane leaks can be caused by poor quality of the subgrade, poor quality of the material placed on the geomembrane, accidents, poor workmanship, and carelessness. describes the electrical methods for locating leaks in Geomembranes Covered with Water or Earth Materials.

Electrical leak location methods are an effective and proven quality assurance measure to locate previously undetected leaks and check the integrity of a liner.

1.1 This standard is a performance-based practice using the water lance system, a electrical method for detecting leaks in exposed geomembranes. For clarity, this document uses the term “leak” to mean holes, punctures, tears, knife cuts, seam defects, cracks and similar breaches in an installed geomembrane.

1.2 This standard can be used for geomembranes installed in basins, ponds, tanks, ore and waste pads, landfill cells, landfill caps, canals, and other containment facilities. It is applicable for geomembranes made of materials such as polyethylene, polypropylene, polyvinyl chloride, chlorosulfonated polyethylene, bituminous geomembrane, and any other electricallyinsulating materials. This standard may not be applicable for locating geomembrane leaks where the proper preparations have not been made during the construction of the facility.

1.3 WarningThe electrical methods used for geomembrane leak location could use high voltages, resulting in the potential for electrical shock or electrocution. This hazard might be increased because operations might be conducted in or near water. In particular, a high voltage could exist between the water or earth material and earth ground, or any grounded conductor. These procedures are potentially VERY DANGEROUS, and can result in personal injury or death. The electrical methods used for geomembrane leak location should be attempted only by qualified and experienced personnel. Appropriate safety measures must be taken to protect the leak location operators as well as other people at the site.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.