2012-10-01_REVISION - M1977248 (3)

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-36- empirical data on clay soils with similar index properties. Permeability tests conducted on samples obtained in the test pits indicate that the in -situ permeabilities of the clays vary from 5 x 10 -8 to 9 x 10 -4 centimeters per second. In our opinion, the permeability of the in -situ materials can be quite variable depending upon their density, Atterberg limits and degree of fissuring. The fissuring results in a blocky secondary structure whose cracks control the overall permeability of the soil mass. Remolded permeabilities of similar clay soils ranged from 1 x 10 -8 to 2 x 10 -6 centimeters per second. The remolded permeabilities average approximately 7 x 10 -7 centimeters per second. The average of the remolded permeabilities is 2 to 3 orders of magnitude lower than the average of the in -situ permeabilities measured. The natural granular soils at the site are generally sands and gravels with some cobbles and boulders to 3 feet in diameter with traces of silt and clay. The granular soils are angular, light moist and light brown, tan and red -brown in color and generally occur in lenses. Based on the resistance to excavation and our examination of the materials exposed in the test pits, we estimate that the granular soils are medium dense to very dense. Empirical correlations developed for similar granular soils indicate that the angles of internal friction for this material should be at least 340.