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Final Construction Quality Assurance Report— WMU FU -13 Forward Landfill Hydraulic Conductivity: Nine in situ soil samples were collected during placement and • compaction of the low permeable clay liner soils and tested for permeability in GLA's 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 are presented in Appendix D. Table 4 presents a summary of the clay liner permeability tests. It should be noted that remolded permeability tests were conducted on the clay borrow soils prior to clay liner construction in the field. Based on the results of this testing, the compaction effort in the field was increased resulting in passing test results. When placement of the low permeable clay liner soils reached the required thickness and elevations, the surface of the compacted clay liner was fine graded by a CAT 140H blade w/GPS and finished with several passes by a vibratory smooth drum roller. GLA's CCW 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 was also monitored for potential desiccation cracking; any suspect • areas were lightly moisture conditioned and reworked by the smooth drum roller. When the clay liner surface preparation was complete, the area was re -inspected by GLA's CCW 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 GLA's CQA Monitor and the installer. The Subgrade Acceptance forms are presented in Appendix E. Survey verification of all lines and grades was performed by RIA & Associates and reviewed by GLA's CQA Officer prior to geosynthetics deployment. 4.4 EARTH FILL SOILS Earth Fill soils were used to construct the temporary south and east termination berms on the floor of FU -13. GLA's CQA Monitor observed construction of the temporary termination berms including placement of "thin" (less than 12 -inch loose lifts) by the scrapers, scrapers splitting their tracks, and additional moisture conditioning added as needed. CCW noted that the soils compacted for the berms were firm and unyielding. Finish grading of the berms was accomplished by the D6 CAT dozer and trimmed to finish grade dimensions by the D6 CAT dozer with slope wings. • 10 14 Geo -Logic ASS 0C I A T E SJ