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File No. 20-1008-36 k" KL E IN FE L D E R July 14, 1995 Installation Circular trenches, approximately 31h and 12 inches deep, were excavated on the bottom 6 inches of the "single-lift" test pads for the inner and outer rings, respectively, using a specially designed cutting tool attached to a drill rig. Since the clay liner has a minimum thickness of 6 inches in this region, the Yh-inch trench depth was approximately 50 percent of the liner (test pad) thickness as recommended by Daniel and Trautwein. The trenches were filled with a bentonite/cement grout, and the rings were set into the trenches. The grout was allowed to harden before the rings were filled with water. A system consisting of a drum, hoses, and a float valve permitted refilling of the outer ring in order to maintain a constant water level. A plastic I.V. bag filled with water was connected to the inner ring and floated in the water of the outer ring, thereby eliminating head differences and minimizing lateral flow between the two rings. Measurements The SDRI's were installed on April 24, 1995, and both rings were filled with water on April 26, 1995. The inner ring was left open to equalize pressure between the two rings. Both rings were checked for leaks. No leaks were detected from the inner ring. A few minor pinhole leaks from the outer rings were fixed by placing bentonite at the leak region. Beginning May 5, 1995, the I.V. bag was filled with water from the outer ring, weighed, and connected to the inner ring. The change in weight of the I.V. bag and the temperature of the water adjacent to the inner ring were monitored daily until May 17, 1995. The three tables below summarize the daily readings; Plates 7, 8, and 9 graphically depict permeability versus time. The actual locations of the SDRI tests were at the centers of Test Pads 2, 3, and 5. It should be noted that the temperature of the water remained fairly constant during testing. No air was observed in the IV bag or tubing connections to the inner ring. Stabilized permeabilities of 2.4 x10-7 cm/sec, 3.0 x 10$ cm/sec, and 1.8 x 10-6 cm/sec for Test Pads 2, 3, and 5, respectively, were achieved. The depth of water in the outer ring was 12-1/2 inches at Test Pad 2, 14 inches at Test Pad 3, and 12 inches at Test Pad 5. The depth of the wetting front was measured at 4 locations inside each SDRI test apparatus ,md was about 2-1/4 inches at Test Pad 2, 2-1/4 inches at Test Pad 3, and 5 inches at Test Pad 5. GSM.°md CH195 Page 6 of 10 July 14, 1995 20-1008-36 0 1995,Kleinfelder,Inc.