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results of the program, which included the following items, are presented in Table 3-1 and laboratory results sheets are presented in Appendix 3-A. • Admixing of the two component clays to the prescribed percentages • Modified Proctor maximum dry density and optimum moisture content deter- minations (ASTM D1557) • Laboratory triaxial permeability testing on - recompacted samples -of admixed clay • Atterberg and Percentage Passing the No. 200 Sieve testing on the pure native and Ione clays The preliminary testing program indicated that even with a 40 percent Ione clay admixture, the required permeability would not be achieved. However, based on CH2M HILL's and Forward's previous experience with Ione * clay admixtures, the laboratory test results were believed to be erroneous, possibly due to improper mixing, inadequate moisture condition- ing, or the existence of clods within the sample. Due to time constraints, further laborato- ry testing was not performed and it was decided to construct two test pads at 25 and 50 percent Ione clay admixtures and perform two SDRI tests. Test Pad Construction and CQA Testing. The test fills were constructed in accordance with the types of equipment, materials, and procedures described in the clay liner specifica- tion (WMU D-93 Design Report). Constructing the test fills entailed: (1) preparing the subgrade soils, (2) mixing, moisture conditioning, placing and compacting the proposed soil mixture in lifts to form the test fills, (3) grading to attain the specified test fill configu- ration, and (4) covering the finished graded test surfaces with 6 -mil plastic sheets to mini- mize moisture losses and development of desiccation cracks prior to installation of the SDRIs. The test pads were constructed in accordance with the SDRI Test Plan, WMU D-93, Forward, Inc. Landfill which is provided in Appendix 3-B. Specific procedures used. to construct the test pads were. as follows: '� • To prepare the admixed clay liner material, two mixing pads were prepared outside the limits of the test pads. The mixing pad subgrades were cleaned of all debris and objectionable materials and graded to provide a level known plane. The mixing pads were then loaded with native clay which was grad- ed to a known thickness. Estimated thicknesses of imported Ione clay were then placed over the native clay. The mixing depths to achieve the 25 % and 50 % target admixtures were then determined by measurement of the in-place dry densities using a nuclear moisture -density gauge. • The soils were mixed and moisture conditioned using a Raygo mixer over a period of two days. Five passes of the mixer were performed. Between the 3rd and 4th passes, the pads were sealed and allowed to moisture condition overnight. After mixing, the admixed soils were ripped using a motor grader SF010012901.wP5 I ], �j