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October 3, 1983 Project 116-1.4 - 2 - which was prepared for this purpose by the chemical laboratory at FMC-Modesto. The results of the permeability tests are summarized in Appendix A and the corresponding lab worksheets requested by Mr. John Marshak are also attached. Permeabilities in the materials used for the sidewall and floor liner, when compacted to 90% of maximum density, generally provides permeability in the range of 10-7 to 10-8 cm/sec. These permeability ranges were confirmed in the testing program on most of the sample pairs. Two samples were tested and found to have permeabilities in the low 10-6 cm/sec. range. Careful examination of the samples tested indicate that the sampling procedure introduced very fine hair-line cracks in the sample, which resulted in the higher than expected fluid velocities. This sample disturbance occurred in soil material which was dry and which had a relatively high silt content. These samples had a high dry strength and required a larger number of blows to drive the penetration sampler. Regardless of the sample character, all permeability tests using both leachate and water as the permeant are at, or well below, the required 10-6 cm/sec. Locations of the sample pairs are shown on Plate 1. Compaction testing on the engineered liners and fluid retention pond embankments was performed by J. H. Kleinfelder & Associates of Stockton, California. A total of 56 tests were taken in accordance with ASTM Test Designation D 2922- 71 (Nuclear Method). The sampling frequency and distribution was conducted in accordance with agreements made with Regional Board Staff during our pre-construction meetings in July 1983. All compaction tests indicate that the required amount of compaction (90% of maximum density) was obtained at all 56 test sites. A summary of the compaction tests and a letter report from J. H. Kleinfelder & Associates is attached in Appendix B. 9Betav4ssociates Q