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n WMU FU -03, WMU F -West Leachate Impoundment and Desilting Basin February 2004 Forward Landfill Job No. 021605.03 shown on the construction drawings. Subgrade fill material was placed in maximum 8 - inch loose lifts and compacted with a CAT 815 sheepsfoot compactor. Moisture was added in place with a water truck and mixed into the soil with a road grader. After the fill material was compacted, field density tests were conducted with a nuclear density gauge to ensure 90% relative compaction and moisture content within ±4% of optimum moisture content (ASTM D 1557). Test and sample locations for the foundation layer soils are included in Appendix D. Vector's CQA Monitor obtained samples of the material for CQA testing to ensure the material met the project specifications. The CQA monitoring of the subgrade fill placement included the following: • Atterberg Limits and Grain Size Analysis of Foundation Layer Soils The CQA testing for the subgrade fill consisted of performing testing for Atterberg limit (ASTM D-4318) and sieve analysis (ASTM D-422) at a frequency of one per 5,000 cubic yards (cy). Five (5) sieve analyses and Atterberg limit tests were performed. The sieve analysis indicated that 100% of the material passed the 3 -inch sieve. The liquid limit and plasticity index for the foundation layer material ranged from 30 to 34 and 9 to 15, respectively. A summary of the test results is included in Table 3. Detailed results of the subgrade fill material testing are included in Appendix C. • Modified Proctor (ASTM D-1557) Approximately 25,000 cy of subgrade fill was placed as the clay liner. Vector's CQA Monitor performed five (5) moisture -density relationships (ASTM D-1557), which corresponds to a frequency of 1 per 5,000 cy. A summary of test results is shown in Table 3. Results of the tests are included in Appendix C. • •U41TA• Vector's CQA Monitor performed 84 passing in-place unit weight testing (ASTM D- 2922) and in-place moisture content (ASTM D-2216) during the compaction of the subgrade fill soil materials. Based on 25,000 cubic yards (cy) of placement, the total number of passing test performed corresponds to a frequency of 1 per 297 cy, which satisfies the minimum required frequency of 1 per 500 cy. Areas that failed to meet the acceptable compaction were reworked and/or replaced and retested until a passing result was achieved. Summaries of the field moisture/density testing are tabulated in Appendix C. Vector Engineering, Inc. - 143E Spring Hill Drive - Grass Valley, CA 95945 - (530) 272-2448 -11-