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