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Western Gravel E &P Waste Disposal Facility October 2011 <br />CQA/QCP Page 16 of 19 <br />GCL seams will be constructed by overlapping adjacent edges a minimum of 6 inches. The minimum <br />overlap at the end of the rolls will be 24 inches <br />Granular bentonite will be used to enhance all seams. The bentonite will be applied at a minimum <br />rate of 0.25 pounds per lineal foot of seam <br />CQA Engineer will observe and document that installer has followed all requirements for placing, <br />seaming and repairing GCL <br />LEAK DETECTION SYSTEM PIPING AND MANHOLES <br />This part of the CQA/QCP describes the piping and manholes that will be used in the construction of the <br />leak detection systems for each of the cells. <br />Piping <br />Slotted PVC collection piping will be surrounded with clean sands as specified in the Earthen Materials <br />section and shown on the Design and Construction Plans. The slotted PVC piping shall consist of <br />Schedule 40 well screen with a maximum slot width of 0.04 ". The collection pipe will connect to s olid <br />Schedule 40 or HDPE (SDR 11) piping that will run under the embankments and into the leak detection <br />manholes. PVC piping shall comply with ASTM D1785 and D2665. HDPE piping shall comply with <br />ASTM D3035 and D3350. No specific field testing of the piping is required; however all piping must be <br />observed and accepted by the CQA Engineer during placement and prior to backfilling. The piping <br />manufacturer's quality assurance (MQA) testing requirements and frequencies are outlined in the <br />following table. <br />PLASTIC PIPING MQA <br />PIPING PROPERTY <br />TEST METHOD <br />TEST FREQUENCY <br />HDPE Resin <br />ASTM D1248 <br />Per MQA document <br />Resin Melt Flow Index <br />ASTM D1238 <br />" <br />Physical Dimensions <br />ASTM D2122 <br />Min 1 test per 10001n ft <br />Resin Density <br />ASTM <br />D1505/D792 <br />" <br />Plate Bearing Test <br />ASTM D2412 <br />" <br />Impact Resistance <br />ASTM D2444 <br />" <br />Manholes <br />The manholes to be used in the leak detection system will be precast concrete structures as shown on the <br />Design and Construction plans. The manhole bases shall be solid concrete structures constructed in a <br />single pour at the plant; therefore there are no joints in the bottom section of the manhole. The joints <br />between the precast manhole sections and above the leak detection pipe will be sealed with a Butyl <br />Rubber Base Flexible Gasket -Type or watertight Fiber Mastic Sealant. The section of leak detection <br />piping entering the manhole will be installed in a watertight rubber boot. No specific field testing of the <br />manhole is required; however the manhole installation must be observed and accepted by the CQA <br />Engineer prior to backfilling. <br />NWCC INC. <br />