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contents were within acceptable range of the nuclear gauge moisture contents. A total of twelve (12) moisture contents (ASTM D-2216) were performed at the specified frequency of 1 per 1,613 cy, which satisfies the minimum test frequency of 1 test per every 2,500 cy of material placed. Areas that failed to meet the acceptable compaction and moisture content were reworked and retested until a passing result was achieved. Summaries of the field nuclear method moisture -density testing are included in Appendix D. Density Verification: To verify the accuracy of the in situ soil densities determined by the nuclear gauge, sand cone tests were performed in conjunction with the nuclear gauge tests. The wet density values obtained by the sand cone test were compared to the nuclear gauge results. Four (4) sand cone tests were performed in the compacted low permeable Clay Liner (CL) soils at a frequency on 1 test per 5,000 cy, which satisfies the minimum specified frequency of 1 sand cone test per 5,000 cy. Results of the Sand Cone density tests are included in Appendix D. Hydraulic Conductivity: Eight (8) in situ soil samples were collected during placement and compaction of the low permeable Clay Liner (CL) soils and tested for permeability in the Ausenco Vector Grass Valley laboratory. Falling head, rising tail water tests were performed in the laboratory according to the procedures outlined in ASTM D-5084. The permeability of the samples met the specified value of 3.1 x10"8 cm/s or lower. Results of the laboratory permeability tests of the low permeable Clay Liner (CL) are presented in Appendix D. Table 5 presents a summary of the low permeable Clay Liner (CL) permeability tests. When placement of the low permeable Clay Liner (CL) soils reached the required thickness and elevations, the surface of the compacted low permeable Clay Liner (CL) was fine graded by a 140H blade w/GPS and finished with several passes by a vibratory smooth drum roller. The Ausenco Vector CQA monitor observed the smooth drum rolling procedure and made recommendations to the Contractor regarding rough areas where ridges or depressions were present; these areas were reworked by the smooth drum roller until a smooth, even surface condition was evident. The surface of the compacted Clay Liner (CL) was also monitored for potential desiccation cracking. Suspect areas were lightly moisture conditioned and reworked by the smooth drum roller. When the Clay Liner (CL) surface preparation was complete, the area was reinspected by the Ausenco Vector CQA monitor and the liner installer; if acceptable, the area was approved for geomembrane placement. Subgrade Acceptance forms for the area to be covered by geosynthetics were filled out and exchanged between the Ausenco Vector CQA monitor and the installer. The Subgrade Acceptance forms are presented in Appendix E. Survey verification of all lines and grades was performed by RJA & Associates and reviewed by the Ausenco Vectors CQA Officer prior to geosynthetics deployment. Date: October 2010 USVC0004800 Final Construction Quality Assurance Report t t