2016-12-07_REVISION - M2009076 - Laserfiche WebLink

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4.5.0 Damaged Material CLC shall inspect the geomembrane after placement and prior to seaming for damage. Any damaged membrane that cannot be reasonably repaired shall be removed and replaced. Repairs to geomembrane shall be made according to procedures described in section 8.2.0. PART IV SEAMING 5.1.0 Required Weather Conditions for Seaming No seaming shall be conducted during periods of excessive moisture, blowing dust, or in the presence of excessive winds(unless wind barriers are provided). Seaming shall not take place in an areas of ponded water. High temperature limits for welding are dependent upon crew safety and membrane material limits. Elevated temperatures can create conditions whereby seam strength may be compromised and an inferior installation may result. When elevated temperature conditions exist over 950 F/35° C,weld quality shall be closely monitored during seaming operations. No seaming shall be conducted during rain or snow, unless the seam is covered with an enclosure permitting favorable seaming conditions. No seaming shall be attempted at ambient temperatures below 5° F without proper pre- heating of material promoting favorable seaming conditions. In all cases, geomembrane shall be dry and protected from wind. CLC shall verify that favorable weather conditions exist and advise the Owner's Representative if they are not favorable. 5.2.0 Seaming and Related Equipment Unless otherwise specified, all field seaming procedures shall be limited to two methods: extrusion welding and fusion (via hot wedge/"wedge welding'. The bulk of all panel to panel seaming shall be performed using the wedge weld technique. Extrusion welding shall limited to areas where wedge welders cannot practically be deployed such as patching and pipe penetration sealing. These machines typically require gas or diesel fueled generators as power sources. Each extrusion welding apparatus shall be equipped with gauges giving the temperature of the apparatus at the nozzle and extruder barrel. Each wedge welding apparatus shall be equipped with gauges giving the applicable temperatures. Although welding over a frozen, wet or muddy subgrade is generally not encouraged, fusion welding may be possible under such conditions by deployment of a movable plastic slip-sheet placed directly below the overlapped membranes being seamed. Properly designed and deployed slip-sheets serve to prevent moisture buildup between the sheets being welded while providing conditions whereby wedge welding machines may be propelled at an uninterrupted rate of speed. Created by Colorado Lining International 1-800-524-8672 5