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and disced to further control moisture and to prepare the soils for use as borrow. ® The •admixed soils were placed on the prepared subgrade in approximately 6 -inch loose lifts. Each lift was compacted with a Caterpillar 824 sheepsfoot compactor with 8 -inch tamping feet. Field and laboratory testing performed on the test pads are presented in Tables 3-2 through 3-9. The test results show that both test pads were compacted to densities greater than 90 percent of the maximum dry density(based on ASTM D 1557) and at moisture contents approximately 2 to 5 percent above optimum moisture content. The admixed clay liner materials have a USCS classification of CL or CH with greater than 70 percent of the particles passing the No. 200 sieve. oratory permeability values for the 25 percent admixture range from 7.0 x 10'9 cm/sec to 1.6 x 10$ cm/sec; laboratory permeabilities for the 50 percent admixture range from 9.2 x 10-9 cm/sec to 7.4 x 10'1 cm/sec. Field and Laboratory testing data sheets are provided in Appendix 3-C and 3-D for the 25 and 50 percent admixture test pads, respectively. SDRI Testing. Two SDRIs were installed and monitored as described in the SDRI Test Plan included in Appendix 3-B. Figures 3-2 and 3-3 present the SDRI permeability results for the 25 and 50 percent admixtures, respectively. The 25 percent test pad indicated a field permeability of approximately 4.5 x 10'1 cm/sec; the 50 percent test pad indicated a field permeability of approximately 2.0 x 10' cm/sec. The 25 percent test pad, therefore, meets the required permeability of 1 x 10' cm/sec while the 50 percent test pad was slight- ly more permeable than required. The 25 percent admix was, therefore, used in construc- tion. Appendices 3-E and 3-F present the raw data (readingl from the SDRI testing. Comparison of the results of. the 25 percent test pad SDRI permeability to the laboratory permeability results presented in Table 3-8 shows that the measured field permeability is about half an order of magnitude greater than the measured laboratory permeability results. Based on this correlation, laboratory permeabilities less than 5 x 10'1 cm/sec- correspond to a field permeability of -1 x 10-1 cm/sec. ` For clay liner construction compliance testing, laboratory permeability testing results which are less than 5 x 10 cm/sec are considered passing. 3.2 Liner Constructs Observation The CQA Inspector obsery hases of the clay liner ins to confirm compliance with the project specifications. Lift ° ses Unum clod sizes were observed to meet the requirements of the technif, i t In addition, the CQA Inspector observed the admixed clay ° terials to identify any d materials which were not acceptable. Th nspector also inspected the admixed materia y wet or dry areas required further moisture conditioning or areas which required fu ix - ng. The CQA Inspector maintained daily inspection diaries noting all construction an sF010012901.WP5 3-7 SX/0111