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3-5 however, considered to be the governing factor in flow or strength conditions of the foundation. The strength of the rock and alluvial soils as selected for stability analysis are discussed in Chapter 4.0. 3.2.2 Hydrologic Parameters Permeability of the alluvial soils as a whole is governed primarily by the layers and/or lenses of clean sands and gravels. As discussed in Section 2.2.1, a permeability value of 50 x 10-5 cm/sec was measured in the alluvial soil layer and is considered representative of the entire layer for the purpose of this evaluation. Less permeable layers and/or topiezometer data suggest interconnection exists. Permeability of the weathered bedrock was assumed equal to the alluvial soil layer as shown in Figure 3 and discussed in Section 2.2.1. As with the alluvial soils, however, preferential flow occurs in the horizontal Idirection. lenses exist within the alluvial soils however. The effect of the less Based on the measurements, tests, and permeable layers is to cause preferential horizontal flow, rather than best be described as flow vertical flow, in some locations. Free flow interconnection between the alluvial soils and the bedrock is not assumed for modeling although topiezometer data suggest interconnection exists. Permeability of the weathered bedrock was assumed equal to the alluvial soil layer as shown in Figure 3 and discussed in Section 2.2.1. As with the alluvial soils, however, preferential flow occurs in the horizontal Idirection. 3.3 FLOW PATHS AND HYDROSTATIC PRESSURES Based on the measurements, tests, and observed seepage flows, the seepage through and beneath the dam can best be described as flow through three different but interconnected systems. As shown schemati- cally in Figure 8, the three flow systems include: o Flow through the upstream dam shell, the core of the dam and into the foundation downstream of the cutoff. o Flow through the pond bottom and dam shell, into the alluvival soils, beneath the cutoff, exiting into the underlying bedrock beneath the down-