GRI-GM19 peel specification

Q: Our liner system is a double composite and along a western tie-in. We need to extrusion-weld the secondary 60-mil (1.5-mm) HDPE (new cell) to an existing secondary 40-mil (1-mm) HDPE (old cell), and the state is continuing to have issues with the fact that we are using the 40-mil (1-mm) GRI-GM19 peel specification as a pass/fail. Can you give a recommendation?

A: When completing a tie-in by extrusion welding the secondary 60-mil (1.5-mm) HDPE (new cell) to an existing secondary 40-mil (1-mm) HDPE (old cell), we recommend using the 40-mil (1-mm) GRI-GM19 peel specification as a pass/fail criterion. The geometry of the seam (weakest point is the thinnest geomembrane) will very quickly lead one to this conclusion after only a few ASTM D6392 shear and peel tests.