Geomembrane Insulation Design

April 1, 2025  |  Q&A: GMA Techline

Q: We have a project where the client has requested us to design a soil cover to protect an HDPE liner from melting due to campfires. The locals like to hang out on the summit of this superfund site and have cookouts, and the privately owned site will not be secured after the 30-year post closure is…
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Geomembrane Seam Sample Testing

April 1, 2025  |  Q&A: GMA Techline

Q: We occasionally receive geomembrane seam samples for testing where LLDPE is welded to HDPE. In this situation, should these samples be tested at 50mm/min. or 500mm/min.? To further complicate this, sometimes these seams are extrusion welds using either HD or LL rod. Does this influence the select…
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Carbon Black

April 1, 2025  |  Q&A: GMA Techline

Q: What is the purpose of “good” carbon black in a geomembrane formulation?
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ASTM D5397 Clarification

April 1, 2025  |  Q&A: GMA Techline

Q: I need some clarification regarding ASTM D5397. One of our baths is having an issue with the agitator. Does it impact the testing if the solution is not agitated continuously?
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Geomembrane Installation Risks

April 1, 2025  |  Q&A: GMA Techline

Q: Could you please let me know if there is any information available on risks associated with installing a geomembrane? Our CQA inspector is pressing us for this because the owner is doing a risk assessment of the geosynthetic installation process.
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GCL Overlaying

April 1, 2025  |  Q&A: GMA Techline

Q: Can you provide information about overlaying a new GCL on hydrated and damaged GCL?
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Surface Impoundment Leak Detection

October 1, 2024  |  Q&A: GMA Techline

Q: We have a double composite surface impoundment with a leak detection between the liner system containing frackwater (brine with high chlorides content) and are seeing evidence of a leak in the primary liner after five years of excellent operations. The pond and leak detection zone (LDZ) levels ha…
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PVC Pipe Leak Repair

October 1, 2024  |  Q&A: GMA Techline

Q: Can buried PVC plastic pipe be repaired? Our pipe has been impacted after being buried for seven years and we are seeing a bit of moisture on the outside of our pressure pipe.
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Critical Geosynthetics Interface

October 1, 2024  |  Q&A: GMA Techline

Q: I have a question regarding critical geosynthetics interface for a final cover system. The cross section from top to bottom is as follows:
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Geomembrane Thermal Expansion and Contraction 

October 1, 2024  |  Q&A: GMA Techline

Q: We are installing geomembrane in extreme weather conditions. We’ve been talking to a client who has a high thermal gradient where temperatures vary in the same day from 55°C to 0°C. He’s been asking us about the thermal expansion and contraction that the geomembrane can present on the field…
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