ASTM D7002-03

Standard Practice for Leak Location on Exposed Geomembranes Using the Water Puddle System

SIGNIFICANCE AND USE
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.
Electrical leak location methods are an effective quality assurance measure to locate previously undetected or missed leaks and check the integrity of a liner.
SCOPE
1.1 This standard is a performance-based practice for electrical methods 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 (as defined in 3.1.5).
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 electrically-insulating materials.
1.3 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.

General Information

• Status: Historical
• Publication Date: 30-Nov-2003
• ICS: 59.080.70 - Geotextiles
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.10 - Geomembranes

Relations

• Replaced By: ASTM D7002-10 - Standard Practice for Leak Location on Exposed Geomembranes Using the Water Puddle System
• Effective Date: 01-Jul-2010
• Referred By: ASTM D7953-20 - Standard Practice for Electrical Leak Location on Exposed Geomembranes Using the Arc Testing Method
• Effective Date: 01-Dec-2003
• Referred By: ASTM D6747-21 - Standard Guide for Selection of Techniques for Electrical Leak Location of Leaks in Geomembranes
• Effective Date: 01-Dec-2003
• Referred By: ASTM D7700-22 - Standard Guide for Selecting Test Methods for Geomembrane Seams
• Effective Date: 01-Dec-2003
• Referred By: ASTM D7909-21a - Standard Guide for Placement of Intentional Leaks During Electrical Leak Location Surveys of Geomembranes
• Effective Date: 01-Dec-2003
• Referred By: ASTM D7703-22 - Standard Practice for Electrical Leak Location on Exposed Geomembranes Using the Water Lance Method
• Effective Date: 01-Dec-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7002 – 03
Standard Practice for
Leak Location on Exposed Geomembranes Using the Water
Puddle System
This standard is issued under the fixed designation D7002; 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 3.1.1 artificial leak, n—an electrical simulation of a leak in
a geomembrane.
1.1 This standard is a performance-based practice for elec-
3.1.2 electrodes, n—the conductive plate that is placed in
trical methods for detecting leaks in exposed geomembranes.
earth ground or in the material under the geomembrane or a
For clarity, this document uses the term “leak” to mean holes,
conductive structure, such as a copper manifold, that is placed
punctures, tears, knife cuts, seam defects, cracks and similar
in the water puddle on the geomembrane.
breaches in an installed geomembrane (as defined in 3.1.5).
3.1.3 electrical leak location, n—a method which uses
1.2 Thisstandardcanbeusedforgeomembranesinstalledin
electrical current or electrical potential to detect and locate
basins, ponds, tanks, ore and waste pads, landfill cells, landfill
leaks.
caps,canalsandothercontainmentfacilities.Itisapplicablefor
3.1.4 geomembrane, n—an essentially impermeable mem-
geomembranes made of materials such as polyethylene,
brane used with foundation, soil, rock, earth or any other
polypropylene, polyvinyl chloride, chlorosulfonated polyethyl-
geotechnical engineering related material as an integral part of
ene, bituminous geomembrane, and any other electrically-
a man made project, structure, or system.
insulating materials.
3.1.5 leak, n—for the purposes of this document, a leak is
1.3 This standard does not purport to address all of the
any unintended opening, perforation, breach, slit, tear, punc-
safety concerns, if any, associated with its use. It is the
ture, crack, or seam breach. Significant amounts of liquids or
responsibility of the user of this standard to establish appro-
solids may or may not flow through a leak. Scratches, gouges,
priate safety and health practices and determine the applica-
dents, or other aberrations that do not completely penetrate the
bility of regulatory limitations prior to use.
geomembrane are not considered to be leaks. Leaks detected
2. Referenced Documents during surveys have been grouped into five categories:
3.1.5.1 holes—round shaped voids with downward or up-
2.1 ASTM Standards:
ward protruding rims.
D4439 Terminology for Geosynthetics
3.1.5.2 tears—linear or areal voids with irregular edge
D6747 Guide for Selection of Techniques for Electrical
borders.
Detection of Potential Leak Paths in Geomembranes
3.1.5.3 linear cuts—linear voids with neat close edges.
3. Terminology
3.1.5.4 seam defects—area of partial or total separation
between sheets.
3.1 Definitions:
3.1.5.5 burned through zones—voids created by melting
polymer during welding.
3.1.6 leak detection sensitivity, n—the smallest leak that the
This practice is under the jurisdiction of ASTM Committee D35 on Geosyn-
leak location equipment and survey methodology are capable
thetics and is the direct responsibility of Subcommittee D35.10 on Geomembranes.
of detecting under a given set of conditions. The leak detection
Current edition approved Dec. 1, 2003. Published December 2003. DOI:
10.1520/D7002-03.
sensitivity specification is usually stated as a diameter of the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
smallest leak that can be reliably detected.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3.1.7 current, n—the flow of electricity or the flow of
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. electric charge.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7002 – 03
3.1.8 water puddle, n—for the purposes of this document, a 4.3 Preparations and Measurement Considerations:
water puddle is a small pool of water being contained and 4.3.1 There must be a conductive material below the
pushed by a squeegee installed on the leak location system. geomembrane being tested. Leak location survey of geomem-
3.1.9 squeegee, n—for the purposes of this document, a brane have been conducted with a conductivity of a subgrade
squeegee is a device used to contain and push water on top of equivalent to sand with moisture greater than 0.7 % (by
an exposed geomembrane. It may consist of a handle and a weight). A properly-prepared subgrade typically will have
transverse piece at one end set with a strip of leather or rubber. sufficiently conductivity. Under proper conditions and prepa-
3.1.10 metalized geotextile, n—a geotextile incorporating rations, geosynthetic clay liners (CGLs) can be also adequate.
metallic strips that can conduct electrical current. 4.3.2 Measures should be taken to perform the leak location
survey when geomembrane wrinkles are minimized. For flex-
4. Summary of Practice
ible geomembranes, sometimes the wrinkles can be flattened
4.1 The Principle of the Electrical Leak Location Method
by personnel walking on them immediately in front of the
Using the Water Puddle System:
survey. For surveys with wrinkles in rigid geomembranes, the
4.1.1 The principle of the electrical leak location method is
leak location survey should be conducted at night or early
to place a voltage across a geomembrane and then locate areas
morning.
where electrical current flows through discontinuities in the
4.3.3 For lining systems comprised of two geomembranes
geomembrane and at seams.
with only a geonet or geocomposite between them, the method
4.1.2 Fig. 1 show a diagram of the electrical leak location
is not applicable. For lining systems comprised of two
method of the water puddle system for exposed geomem-
geomembranes separated by a metalized geotextile, the method
branes. One output of an electrical excitation power supply is
is applicable.
connected to an electrode placed in a water puddle created on
4.3.4 For best results, conductive paths such as metal pipe
top of the geomembrane. The other output of the power supply
penetrations, pump grounds, and batten strips on concrete
is connected to an electrode placed in electrically conductive
should be isolated or insulated from the water puddle on the
material under the geomembrane.
geomembrane. These conductive paths conduct electricity and
4.1.3 Measurements are made using an electrical current
mask nearby leaks from detection.
measurement system, the magnitude of the current being
4.3.5 The system specifications are presented in Table 1.
related to the size of the leak.An electronic assembly is usually
5. Significance and Use
used to produce an audio tone whose frequency is proportional
to the current flow.
5.1 Geomembranes are used as barriers to prevent liquids
4.2 Leak Location Surveys of Exposed Geomembrane Using
fromleakingfromlandfills,ponds,andothercontainments.For
the Water Puddle System:
this purpose, it is desirable that the geomembrane have as little
4.2.1 The water puddle detection system usually consists of
leakage as practical.
a horizontal water spray manifold with multiple nozzles that
5.2 The liquids may contain contaminants that if released
spray water onto a geomembrane, a squeegee device to push
can cause damage to the environment. Leaking liquids can
the resultant puddle of water, and a handle assembly as shown
erodethesubgrade,causingfurtherdamage.Leakagecanresult
in Fig. 2.Apressurized water source, usually from a tank truck
in product loss or otherwise prevent the installation from
parked at higher elevation, is connected to the spray manifold
performing its intended containment purpose.
using a plastic or rubber hose. Figs. 3 and 4 show one example
5.3 Geomembranes are often assembled in t
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