ASTM D8265-19

Standard Practices for Electrical Methods for Mapping Leaks in Installed Geomembranes

SIGNIFICANCE AND USE
4.1 Geomembranes are used as impermeable barriers to prevent liquids from leaking from landfills, ponds, and other containment facilities. 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. For these reasons, it is desirable that the geomembrane have as little leakage as practical.  
4.2 Geomembrane leaks can be caused by poor quality of the subgrade, poor quality of the material placed on the geomembrane, accidents, poor workmanship, manufacturing defects, and carelessness.  
4.3 The most significant causes of leaks in geomembranes that are covered with only water are related to construction activities, including pumps and equipment placed on the geomembrane, accidental punctures, and punctures caused by traffic over rocks or debris on the geomembrane or in the subgrade.  
4.4 The most significant cause of leaks in geomembranes covered with earthen materials is construction damage caused by machinery that occurs while placing the earthen material on the geomembrane. Such damage also can breach additional layers of the lining system such as geosynthetic clay liners.  
4.5 Electrical leak location methods are used to detect and locate leaks for repair. These practices can achieve a zero-leak condition at the conclusion of the survey(s). If any of the requirements for survey area preparation and testing procedures is not adhered to, then leaks could remain in the geomembrane after the survey. Not all of the survey area requirements are possible to achieve at some sites, but the closer the site can come to the ideal condition, the more successful the method will be.
SCOPE
1.1 These practices describe standard procedures for using electrical methods to locate leaks in geomembranes covered with liquid or earthen materials, which can be watered to cause leakage through the geomembrane. For clarity, these practices use the term “leak” to mean holes, punctures, tears, knife cuts, seam defects, cracks, and similar breaches in an installed geomembrane (as defined in 3.2.7).  
1.2 These practices are intended to ensure that leak location surveys are performed to the highest technical capability of electrical methods, which should result in complete liquid containment (no leaks in geomembrane).  
1.3 Not all sites will be easily amenable to this method, but some preparation can be performed in order to enable this method at nearly any site.  
1.4 The geomembrane must be covered with water or as wet as practical. Earthen materials or sludge, or both, may also be present over the geomembrane. The main requirement is that a hydraulic gradient exist across the geomembrane so that if a hole or breach exists in the geomembrane, it will actively leak during the testing. If ideal testing conditions cannot be achieved, the method can still be performed, but any issues with site conditions are documented.  
1.5 Leak location surveys can be used on geomembranes installed in basins, ponds, tanks, ore and waste pads, landfill cells, landfill caps, and other containment facilities. The procedures are applicable for geomembranes made of materials such as polyethylene, polypropylene, polyvinyl chloride, chlorosulfonated polyethylene, bituminous material, and other sufficiently electrically insulating materials.  
1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.7 The electrical methods used for geomembrane leak location should be attempted only by qualified and experienced personnel. Appropriate safety measures should be taken to protect the leak location operators, as well as other people at the site. A current limiter of no greater than 290 mA should be used for all direct current power sources used to...

General Information

• Status: Historical
• Publication Date: 31-Jul-2019
• ICS: 91.100.50 - Binders. Sealing materials
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.10 - Geomembranes

Relations

• Referred By: ASTM D6747-21 - Standard Guide for Selection of Techniques for Electrical Leak Location of Leaks in Geomembranes
• Effective Date: 01-Aug-2019
• Referred By: ASTM D7700-22 - Standard Guide for Selecting Test Methods for Geomembrane Seams
• Effective Date: 01-Aug-2019
• Referred By: ASTM D7909-21a - Standard Guide for Placement of Intentional Leaks During Electrical Leak Location Surveys of Geomembranes
• Effective Date: 01-Aug-2019

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D8265 − 19
Standard Practices for
Electrical Methods for Mapping Leaks in Installed
1
Geomembranes
This standard is issued under the fixed designation D8265; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope personnel. Appropriate safety measures should be taken to
protect the leak location operators, as well as other people at
1.1 These practices describe standard procedures for using
the site.Acurrent limiter of no greater than 290 mAshould be
electrical methods to locate leaks in geomembranes covered
used for all direct current power sources used to conduct the
with liquid or earthen materials, which can be watered to cause
survey.
leakage through the geomembrane. For clarity, these practices
1.8 This standard does not purport to address all of the
use the term “leak” to mean holes, punctures, tears, knife cuts,
safety concerns, if any, associated with its use. It is the
seam defects, cracks, and similar breaches in an installed
responsibility of the user of this standard to establish appro-
geomembrane (as defined in 3.2.7).
priate safety, health, and environmental practices and deter-
1.2 These practices are intended to ensure that leak location
mine the applicability of regulatory limitations prior to use.
surveys are performed to the highest technical capability of
1.9 This international standard was developed in accor-
electrical methods, which should result in complete liquid
dance with internationally recognized principles on standard-
containment (no leaks in geomembrane).
ization established in the Decision on Principles for the
1.3 Not all sites will be easily amenable to this method, but
Development of International Standards, Guides and Recom-
some preparation can be performed in order to enable this
mendations issued by the World Trade Organization Technical
method at nearly any site.
Barriers to Trade (TBT) Committee.
1.4 The geomembrane must be covered with water or as wet
2. Referenced Documents
as practical. Earthen materials or sludge, or both, may also be
2
2.1 ASTM Standards:
present over the geomembrane. The main requirement is that a
D4439 Terminology for Geosynthetics
hydraulic gradient exist across the geomembrane so that if a
hole or breach exists in the geomembrane, it will actively leak
3. Terminology
during the testing. If ideal testing conditions cannot be
3.1 For general definitions related to geosynthetics, see
achieved, the method can still be performed, but any issues
Terminology D4439.
with site conditions are documented.
3.2 Definitions of Terms Specific to This Standard:
1.5 Leak location surveys can be used on geomembranes
3.2.1 anomaly, n—electrical measurement caused by some
installed in basins, ponds, tanks, ore and waste pads, landfill
aberration in the survey area, which may or may not be a leak.
cells, landfill caps, and other containment facilities. The
proceduresareapplicableforgeomembranesmadeofmaterials
3.2.2 conductive-backed geomembrane, n—a specialty
such as polyethylene, polypropylene, polyvinyl chloride, chlo-
geomembrane manufactured using co-extrusion technology
rosulfonated polyethylene, bituminous material, and other
featuring an insulating layer in intimate contact with a conduc-
sufficiently electrically insulating materials.
tive layer.
1.6 The values stated in SI units are to be regarded as 3.2.3 current source electrode, n—the electrode that is
standard. No other units of measurement are included in this placed in the water or earthen material above the geomem-
standard. brane.
3.2.4 dipole measurement, n—an electrical measurement
1.7 The electrical methods used for geomembrane leak
made on or in a partially conductive material using two closely
locationshouldbeattemptedonlybyqualifiedandexperienced
spaced electrodes.
1
These practices are under the jurisdiction of ASTM Committee D35 on
2
Geosynthetics and are the direct responsibility of Subcommittee D35.10 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Geomembranes. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Current edition approved Aug. 1, 2019. Published August 2019. Originally Standards volume information, refer to the standard’s Document Summary page on
approved in 2019. DOI: 10.1520/D8265-19. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D8265 − 19
3.2.5 earthen material, n—sand, gravel, clay, silt, combina- the geomembrane. Such damage also can breach additiona
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