Oh, the value of electrical liner integrity surveys.
Rick Thiel (Thiel Engineering) recounts his strong urging of a client to perform an electrical integrity survey on a newly installed MSW landfill bottom liner. The owner was not too keen due to the fact that, even by Rick’s assessment, both the installation and CQA were of a high quality. But, Rick prevailed. The survey uncovered two small holes and a 3 ft long bulldozer tear, right at the deepest part of the landfill. The owner committed to doing electrical surveys on all future installations!
A similar tale is told by Ian Peggs (I-CORP) after performing a rapid gas survey to locate leaks in a single geomembrane landfill cap. Again the owner felt satisfied with construction and CQA. Nine leaks were found in 15 acres. One was an 18 in. long equipment tear
Figure 1 |
and two were holes made by large rocks in the sand drainage layer covering the geomembrane (Figures 2 and 3).
Figure 2 | Figure 3 |
One wonders how such things can happen. But that’s why we do leak surveys. It’s not the pinhole seam leaks we need to worry about, it’s the equipment gouges!