2012-09-06_REVISION - M2008070 (18)

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Western Gravel E &P Waste Disposal Facility October 2011 CQA/QCP Page 9 of 19 Engineer that is compatible with the geomembrane roll numbering system. Copies of warranties for the manufacturer and installer must also be provided to the CQA Engineer at this time • Installer must provide documentation that the Superintendent and or Master Seamer have experience managing a minimum of four installation projects for a minimum of 2,000,000 sq. ft. of HDPE installation Construction: • The CQA engineer and geomembrane installer will observe, inspect and approve the completed subgrade just prior to installing the secondary HDPE liner • The geomembrane installer will certify in writing that the surface on which the secondary HDPE liner will be placed is acceptable. This certification of acceptance will be given to the CQA Engineer just prior to the installation of the HDPE • CQA Engineer will visually inspect the HDPE for defects, damage and abnormalities as the panels are placed and determine if any panels should be rejected, repaired or accepted • Trial seams will be tested by the installer with each piece of seaming equipment while the seaming of the panels is being conducted. A minimum of two trial seams per day will be conducted with one trial prior to start of daily seaming and the second trial at mid -shift. Additional seam trials may be required by the CQA Engineer depending on the number of seam welders on the site and the weather conditions • Each field seam will be nondestructively tested over the full length of the seam by the installer using vacuum box procedures. Where vacuum box testing is not feasible, seams shall be tested by the air lance method • CQA Engineer will visually inspect seams for defects, damage and abnormalities and observe the nondestructive seam testing. Any seams that fail examination will be marked by CQA Engineer and repaired by installer • Destructive seam testing shall be conducted throughout the seaming process at the field seam locations determined by the CQA Engineer at a minimum rate of one sample for every 750 lineal feet of seam. Destructive seam samples will be sent by CQA Engineer to independent laboratory for strength testing • CQA Engineer will verify that the liner materials have been properly anchored in the anchor trench Gennetc A geocomposite drainage net (geonet) will be placed between the secondary and primary HDPE liners and used as the primary component of the leak detection system across the sides and base of the impoundments. A one -sided composite geonet with the 6- oz /yd2 non -woven fabric facing upward will be placed over the 60 -mil liner used to aid leachate collection. The geonet will be placed in the anchor trench in a similar manner to the HDPE liner materials. The geonet shall consist of HDPE materials that meet the properties listed in the following table s. NWCC INC.