Laserfiche WebLink
Forward Landfill WMU FU-23 <br />02778 16 HDPE GEOMEMBRANE <br />i. A vacuum box assembly consisting of a rigid housing, a transparent viewing window, a soft neoprene gasket attached to the bottom, port hole, or valve assembly, and a vacuum gauge. ii. A vacuum pump assembly equipped with a pressure control iii. A rubber pressure/vacuum hose with fittings and connections. iv. A soapy solution and an applicator. b. Test Procedures. i. Place the box over the wetted seam area (soapy solution). ii. Ensure that a leak-tight seal is created. iii. Energize the vacuum pump and reduce the vacuum box pressure to approximately 10 inches of mercury, i.e., 5 psi gauge. iv. Examine the geomembrane through the viewing window for the presence of soap bubbles for a period of not less than 10 seconds. v. Mark all areas where soap bubbles appear and repair in accordance with repair procedures described in this specification. 3. Air pressure testing for seaming processes producing a double seam with an enclosed channel. a. Equipment, comprised of the following: i. An air pump (manual or motor driven) equipped with a pressure gauge capable of generating and sustaining a pressure over 40 psi and mounted on a cushion to protect the geomembrane. ii. A rubber hose with fittings and connections. iii. A sharp hollow needle, or other approved pressure feed device. iv. A pressure gauge with an accuracy of plus or minus 1 psi. b. Test Procedures. i. Seal both ends of the welded seam to be tested. ii. Insert needle or other approved pressure feed device into the tunnel created by the weld. iii. Energize the air pump to a minimum pressure of 30 psi or 1/2 psi per mil of liner thickness, whichever is greater, close valve and sustain pressure for at least 5 minutes. iv. If loss of pressure exceeds 2 psi (10 mm mercury), or otherwise approved, or does not stabilize, locate faulty area and repair in accordance with repair procedures described in this specification. v. Puncture opposite end of seam to release air. If blockage is present, locate and test seam on both sides of blockage. vi. Remove needle or other approved pressure feed device and seal the penetration holes. 4. Spark Testing for penetrations or other difficult areas not accessible for vacuum testing. a. Equipment and Materials. i. 24-gauge copper wire. ii. Low-amperage electric detector, 20,000 to 30,000 volts, with