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• Equipment used for seaming will not damage the VFPE. The extruder is purged prior to beginning a seam until all the heat -degraded extrudate is removed (extrusion welding only). • Seam grinding has been completed less than 1 hour before seam welding (extrusion welding only). • The ambient temperature measured 6 inches above the VFPE surface is between 40 and 105 degrees Fahrenheit and relative humidity is less than 80 percent. The end of welds more than 5 minutes old, are ground to expose new material before restarting a weld (extrusion welding only). • The weld is free of dust and other debris. • For cross seams, the seam is ground to a smooth incline prior to welding. The seams are overlapped in a downgradient direction with a minimum overlap of 4 inches. • No solvents or adhesives are present in the seam area. • The procedure used to temporarily hold the panels together does not damage the panels and does not preclude Geotechnical CQA testing. The panels are being seamed in accordance with the Project Plans and Specifications using approved equipment with gauges giving applicable temperatures. • There is no free moisture in the weld area. . The electric generator is placed on a smooth base such that no damage occurs to the VFPE. • A smooth insulating plate or fabric is placed beneath the hot welding apparatus after use. • The geomembrane is protected from damage in heavily trafficked areas. The Geotechnical CQA Monitors shall log all appropriate temperatures and conditions, and shall log and report to the Geotechnical CQA Officer any -non- compliance. Trial Seams Trial seam samples are not removed from installed seams, but are made along side the seaming work area by the Liner Subcontractor using a fragment of the erne VFPE sheet and the same installation procedures as for the VFPE installation itself. As such, they are considered nondestructive samples. Such trial seams shall be made at the beginning of each seaming period (start of day, mid-day, and anytime the equipment is shut down or the seaming operation is suspended for more than 1/2 hour) for each piece of seaming equipment used that day. In addition, each welder shall make at least one trial seam each day. Trial seams shall be made under the same conditions as those anticipated for actual seams. The trial seam sample shall be at least 3 ft. long by 1 ft. plus the seam width wide (after seaming) with the seam centered lengthwise. Seam overlap shall be as per 40 the Specifications. -23- C:\2001-048\FINAL COVER_CQA.DOC\08/20/01 Geologic Associates