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1 Vector CQA monitor and the liner installer, COMANCO, to verify that surface was acceptable for the overlying geosynthetics. When both parties agreed that the soil surface was acceptable for geosynthetics deployment Subgrade Acceptance forms were prepared and copies exchanged by Ausenco Vector CQA and the installer's superintendent. The signed Subgrade Acceptance forms are presented in Appendix E. 4.3 Low Permeability Clay Liner Approximately 19,360 cy of material was utilized to construct a 2 -feet thick layer of low permeable Clay Liner (CL) on the floor of WMU FU -10. The soil borrow for this material was adjacent the southeast corner on the module. Before placement, the contractor ripped and moisture conditioned the soil borrow area. Scrapers collected the material and placed it on prepared soil surface (compacted, scarified, moisture 'conditioned Subgrade Fill) in 6 -inch to 8 -inch loose lifts; additional water was added as needed and compaction achieved by the 815 sheepsfoot and loaded scraper traffic. The surface of each lift of the low permeable Clay Liner (CL) was moisture conditioned and scarified by the 815 compactor before the next lift was placed to produce a 2 -foot thick layer of homogeneous material. The Ausenco Vector CQA monitor performed 81 passing in-place nuclear method moisture -density tests during placement of the low permeable Clay Liner (CL) soils. The Specifications required this material to be compacted to a minimum 90 percent of the maximum dry density of an ASTM D1557 Proctor, at a moisture content 3 % to 6 % above the optimum moisture content (OMC). Summaries of the field nuclear method moisture -density tests performed in the compacted low permeable Clay Liner (CL) are included in Appendix D. The required testing frequencies and number of tests taken are presented in Table 1. The Ausenco Vector CQA monitor performed Proctor Compaction moisture -density relationships (ASTM D -1557A) tests, Atterberg Limits determination (ASTM D-4318), and grain size distribution (ASTM D-422) tests on the low permeable Clay Liner (CL) material during placement. Modified Proctor (ASTM D-1557): The Ausenco Vector CQA monitor performed five (5) moisture - density relationships tests (ASTM D-1 557A Proctor), including one check point, on the low permeable Clay Liner (CL) soils. These reference curves were used in the field during compaction testing and compared to the moisture and compaction of the in situ Clay Liner (CL) after placement by the contractor. These tests performed by Ausenco Vector CQA correspond to a frequency of one test per 3,872 cy of material, and satisfies the minimum required frequency of 1 test per 5,000 cy. A summary of these test results is shown in Table 5. Results of these tests are included in Appendix D. Atterberg Limits and Grain Size Analysis of Clay Liner Soils: The Ausenco Vector CQA testing of the low permeable Clay Liner (CL) soils included Atterberg Limits determination (ASTM D-4318); and Sieve Analysis (ASTM D-422), including -200 wash (ASTM D-1140). The specified frequency for these tests was 1 test per 2,500 cy; Ausenco Vector CQA performed 8 Atterberg°s and Sieve Analysis' on the low permeable Clay Liner (CL) soils, at a testing frequency of 1 test per 2,420 cy. A summary of these test results is included in Table 4. Detailed results of the low permeable Clay Liner (CL) material testing are included in Appendix D. Moisture and Density Testing: The Ausenco Vector CQA monitor recorded 81 passing nuclear method in-place unit weights (ASTM D-2922) and in-place moisture contents (ASTM D-3017) during the compaction of the low permeable Clay Liner (CL) soils. The total number of passing tests recorded corresponds to a frequency of 1 test per 239 cy, which satisfies the minimum required frequency of 1 test per 250 cy. In addition, samples were collected at random moisture -density test locations for oven and micro wave moisture determination. The moisture samples are used to check 0 the accuracy of the nuclear moisture -density gauge. It was determined that the oven moisture Date: October 2010 USVC0004800 Final Construction Quality Assurance Report 10