Abstract
The most significant damage to installed geomembranes is caused during cover material placement and can typically only be found if covered geomembrane testing is performed using electrical leak location methods. Recent advancements in covered geomembrane electrical leak location testing include an improved dipole method testing ASTM standard practice. In this paper, the technical issues with previously used dipole method standard procedures are explained along with a detailed description of how the improved practice addresses those technical flaws. In addition, testing effectiveness is improved by the new standard practice through controlling site conditions, standardizing measurement density as a function of the dipole spacing, providing procedures for optimizing sensitivity, and enhancing reporting requirements to enable reviewability. Reporting examples of the testing methods are provided, advancements in dipole method equipment for faster and more precise testing are discussed, and recommendations are made for further optimizing testing effectiveness. As a result of the testing methodology advancements, covered geomembrane testing can be performed with the certainty of locating all installation damage before the operational life of a containment facility.
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References
Forget B, Rollin A L, Jacquelin T (2005) Lessons Learned from 10 years of leak detection surveys on geomembranes. In: Proceedings of the 10th international waste management and landfill symposium, 3–7 October 2005, S. Margherita di Pula, Cagliari, Italy, 9 pp
Nosko V, Crowther J (2015) Can the Holy Grail of the Geosynthetics Industry “zero Leakage” be Achieved by Arc Testing? In: Proceedings of the 2015 Geosynthetics conference, 15–18 February, Portland, OR, USA, 12 pp
Rowe RK (1998) Geosynthetics and the minimization of contaminant migration through barrier systems beneath solid waste. In: Proceedings of the sixth international conference on geosynthetics, Atlanta, GA, USA, pp 27–102
Gilson-Beck A (2019) Controlling leakage through installed geomembranes using electrical leak location. Geotext Geomembr 47:697–710
ASTM D7007–16. Standard practices for electrical methods for locating leaks in geomembranes covered with water or earthen materials
ASTM D7909–21a. Standard guide for placement of intentional leaks during electrical leak location surveys of geomembranes
ASTM D8265–21. Standard practices for electrical methods for mapping leaks in installed geomembranes
Gilson A (2019) Electrical leak location testing for zero leak verification. In: Proceedings of IFAI Geosynthetics conference, 10–13 Feb 2019, Houston, Texas, USA, pp 45–54
Cen WJ, Du XH, He HN, Yan J, Rahman MS (2020) Laboratory testing and numerical modeling of geomembrane electrical leak detection surveys. Geosynth Int 27(5):490–502
Gilson-Beck A (2021) Dipole measurement density and dipole spacing for electrical leak location. In: Proceedings of IFAI Geosynthetics conference, 21–41 Feb 2021, Kansas City, MO, USA, pp 144–155
Lugli F, Mahler CF (2016) Analytical study of the performance of a geomembrane leak detection system. Waste Manage Res 35(5):482–486
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Appendix
Appendix
Date.
Client Info.
Subject: Final Report for Electrical Leak Location Testing of X Project.
Dear Client,
This report documents the electrical leak location test conducted by Company X at Project X located in City, State.
The liner system consisted of, from top to bottom, ~ 2’ sand cover material, geocomposite, HDPE geomembrane, GCL, and prepared low permeability subgrade. The test was performed on Date X. The weather was cool and clear to cloudy during the testing.
This report describes the methods, procedures, and results of the test.
Dipole Method
The method used to perform the electrical leak location test on the installed geomembrane was the dipole method in accordance with ASTM D7007. A DC voltage was applied to the material covering the geomembrane and the power source was grounded to the underlying conductive layer. A roving 3-m dipole operated by Person X was used to measure voltage potential. The operator observed and recorded voltage potential measurements in a grid pattern throughout the testing area.
Results
Prior to the dipole method test, a leak detection distance test was performed with an artificial leak. The artificial leak consisted of a 6.4 mm diameter electrode. A 3.0:1 signal to noise ratio could not be obtained so the test was performed at a measurement grid spaced at 1 m ×1 m.
No leak signatures were detected.
Signed,
Person Y.
Test report 1 Example of report from D7007-16 test where leaks were not found and issues with site conditions existed.
Date.
Client Info.
Subject: Final Report for Electrical Leak Location Testing of X Project.
Dear Client,
This report documents the electrical leak location test conducted by Company X at Project X located in City, State.
The liner system consisted of, from top to bottom, ~ 2’ sand cover material, geocomposite, HDPE geomembrane, GCL, and prepared low permeability subgrade. The test was performed on Date X. The weather was cool and clear to cloudy during the testing.
This report describes the methods, procedures, and results of the test.
Dipole Method
The method used to perform the electrical leak location test on the installed geomembrane was the dipole method in accordance with ASTM D7007. A DC voltage was applied to the material covering the geomembrane and the power source was grounded to the underlying conductive layer. A roving 3-m dipole operated by Person X was used to measure voltage potential. The operator observed and recorded voltage potential measurements in a grid pattern throughout the testing area.
Results
Prior to the dipole method test, a leak detection distance test was performed with an artificial leak. The artificial leak consisted of a 6.4 mm diameter electrode. A signal to noise ratio of greater than 3.0:1 was obtained at an offset of 2 m from the artificial leak so the test was performed at a measurement grid spacing of 3 m × 3 m.
No leak signatures were detected.
Signed,
Person Y.
Test report 2 Example of report from D7007-16 test where leaks were not found.
Date.
Client Info.
Subject: Final Report for Electrical Leak Location Testing of X Project.
Dear Client,
This report documents the electrical leak location test conducted by Company X at Project X located in City, State.
The liner system consisted of, from top to bottom, ~ 2′ sand cover material, geocomposite, HDPE geomembrane, GCL, and prepared low permeability subgrade. The test was performed on Date X. The weather was cool and clear to cloudy during the testing.
This report describes the methods, procedures, and results of the test.
Dipole Method
The method used to perform the electrical leak location test on the installed geomembrane was the dipole method in accordance with ASTM D7007. A DC voltage was applied to the material covering the geomembrane and the power source was grounded to the underlying conductive layer. A roving 3-m dipole operated by Person X was used to measure voltage potential. The operator observed and recorded voltage potential measurements in a grid pattern throughout the testing area.
Results
Prior to the dipole method test, a leak detection distance test was performed with an artificial leak. The artificial leak consisted of a 6.4 mm diameter electrode. A signal to noise ratio of greater than 3.0:1 was obtained at an offset of 2 m from the artificial leak so the test was performed at a measurement grid spacing of 3 m× 3 m.
One leak was detected. The leak was a linear tear and measured approximately 0.75 m long. The approximate location of the leak is shown below.
Location of damage detected.
Signed,
Person Y.
Test report 3 Example of report from D7007-16 test where leaks were found.
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Gilson, A. Advancements in Field Testing for Locating Geomembrane Installation Damage. Int. J. of Geosynth. and Ground Eng. 7, 72 (2021). https://doi.org/10.1007/s40891-021-00309-3
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DOI: https://doi.org/10.1007/s40891-021-00309-3