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KLEINFELDER File No. 20-1008-49.001 August 19, 1994 Equipment The SDRI used for our testing program consisted of two rings fabricated from heavy plastic and fiberglass. The inner ring was 24 inches in diameter, I/4-inch thick, domed, and approximately 8 inches high. The outer ring was 72 inches in diameter, approximately 34 inches high, and sealed to reduce evaporation. During the test, the applied head in the outer and inner rings was kept constant and identical to minimize the hydraulic head trending to drive flow between the inner and outer rings. Additionally, by keeping the water levels constant, the tendency for the inner ring to expand or contract with time was minimized and enhanced one-dimension infiltration flow (vertical) from the inner ring. The SDRI equipment used for our testing program is shown schematically on Plate 2. Installation Circular trenches, approximately 3'/a and 14 inches deep, were excavated 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, these trench depths were 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 was installed on August 3, 1994, and both rings were filled with water on August 4, 1994. 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 ring were fixed by placing bentonite at the leak region. Beginning August 9, 1994, 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 August 18, 1994. The table below summarizes the daily readings; Plate 2 graphically depicts permeability versus time. The actual location of the SDRI test was at North 1171, East 1112 at a depth of 0.5' on the "single-lift" pad. 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. A stabilized permeability of 4.5x10'8 cm/sec was achieved. The depth of water in the outer ring was 12 inches. The depth of the wetting front was measured at 4 locations inside the SDRI test apparatus and was about 1 inch. GSM:md 13/94 Copyright 1994 Kteinfelder, Inc. Page 5 of 7