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• Verify that methods used to deploy the geomembrane minimize wrinkles and that panels are anchored to prevent movement by the wind. Verify that the Contractor corrects any damage resulting to or from windblown geomembrane. • Verify that no more panels are deployed than can be seamed on the same day. The QA/QC Inspector must inform both the Geosynthetics Contractor and the QA/QC Manager if any of the above conditions are not met. Field Seaming. Before the start of geomembrane welding and during welding operations, each welder and welding apparatus will be tested in accordance with the specifications to verify that the equipment is functioning properly. One trial weld will be taken before the start of work and one at mid-shift. The trial weld sample will be 3-feet-long and 12-inches-wide, with the seam centered lengthwise. The QA/QC Inspector will observe all welding operations and verify that the Geosynthetics Contractor quantitatively tests each trial weld for peel adhesion(ASTM D 413)and bonded seam strength(ASTM D 3083). (Peel adhesion tests will be referred to as"peel'and bonded seam strength tests will be referred to as"shear"in this manual.) The purpose of peel and shear tests is to evaluate seam strength and to evaluate long-term performance. Shear strength measures the continuity of tensile strength through the seam and into the parent material. Peel adhesion measures the strength of the bond created by the welding process. The results of the peel and shear tests will be recorded on the trial weld form. Trial welds must be completed under conditions similar to those under which the panels will be welded. Trial welds must meet specified requirements for peel and shear and the failure must be ductile or a film tearing bond(FTB)for a wedge weld.An FTB means the test specimen breaks at the edge of the outside of the seam,but not in the same seam. If at any time the QA/QC Inspector believes that welding apparatus is not functioning properly, a trial weld must be performed. If there are wide changes in temperature (> 300F.),humidity, or wind speed, another trial weld must be performed. The trial weld must be allowed to cool to ambient temperature before it is tested. During geomembrane welding operations, the QA/QC Inspector will: • Verify that the Geosynthetics Contractor has the number of welding apparatuses and spare parts necessary to perform the work. • Verify that equipment used for welding will not damage the geomembrane. • Verify that extrusion welders are purged before beginning a weld so that all heat- degraded extrudate is removed from the nozzle of the welder. • Verify that seam grinding is completed less than 1 hour before seam welding, and the upper sheet is beveled (extrusion welding only). • Verify that ambient temperature measured 6-inches above the geomembrane surface is Page 24