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Section 02776 <br />Geomembrane <br />done during any precipitation, in the presence of excessive moisture (e.g., fog, rain, dew) or in the <br />presence of excessive winds, as determined by the CQA Monitor. <br />F. Following the installation of the geomembrane, an examination of the entire surface shall be <br />conducted to detect potentially harmful rocks or other objects. Any such objects will be removed <br />and the geomembrane repaired by the CONTRACTOR, at no cost to CC &V. <br />3.06 FACTORY SEAMS <br />MANAGER and CERTIFYING ENGINEER may require CONTRACTOR to test up to as much as <br />twenty percent (20 %) of factory fusion welds (non- destructive air pressure test) in the field to verify factory <br />test results. Additional testing at CONTRACTOR's expense will be required if failed tests are obtained in <br />the field. <br />3.07 FIELD SEAMS <br />A. Seam Layout <br />1. Seams shall be oriented parallel to the line of maximum slope, i.e., oriented down, not <br />across the slope. In corners and odd - shaped geometric locations, the number of field <br />seams shall be minimized. <br />2. No horizontal or base T -seam or tie -in seams shall be closer than five (5) feet from the toe <br />of the slope. Seams shall be aligned to prevent wrinkles and "fish mouths." If a fish <br />mouth or wrinkle is found, it shall be relieved and capped. <br />3. Panels of geomembrane will have sufficient overlap provided to allow peel tests to be <br />performed on the seam. <br />B. Seaming Method <br />1. The procedure used to temporarily bond adjacent panels together shall not damage the <br />geomembrane; in particular, the temperature of hot air at the nozzle of any spot welding <br />apparatus shall be controlled such that the geomembrane is not damaged. <br />2. CONTRACTOR shall use double fusion welding as primary method of seaming adjacent <br />field panels. <br />a. For cross seam tees associated with fusion welding, CONTRACTOR shall <br />patch panel intersections consisting of three or more panels and extrusion weld <br />to a minimum distance of 4 inches on each side of patch. The edge of the sheet <br />shall be ground to a 45° angle prior to welding. <br />b. Place a protective layer, e.g., insulting plate or fabric, beneath hot welding <br />apparatus after usage. <br />c. When subgrade conditions dictate, use a moveable protective layer directly <br />below each overlap of geomembrane that is to be seamed to prevent buildup of <br />moisture between sheets and prevent debris from collecting around pressure <br />rollers. <br />C \AMEC_CC &V\Phase 5 VLF \PSSA Cert Repor\Appendices\Appendix E \SPECS \02776 r1 doc <br />Page 15 of 22 September 3, 2008 <br />Revision 1 <br />