Infrared thermography may be the next step in nondestructive testing of seams for certain geomembranes. Solmax has announced its use of this testing approach. Read about it here. And for more about infrared thermography, read Ian D. Peggs’ (I-CORP INTERNATIONAL)accounts of the technology’s capabilities: Tech Note 1 can be found at the link: https://www.geosynthetica.net/tech_docs/GCLUnderBlackGeomembrane.asp and Tech Note 2 can be found at https://www.geosynthetica.net/tech_docs/GCLUnderPP.asp (please cut and paste into your browser).