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1-3 <br />to be eroded by the observed seepage mechanisms. Chapter 4.0 discusses <br />how these assessments were conducted and presents the quantitative <br />results of these evaluations. <br />Conclusions were drawn as to the condition of the dam based on the model <br />of existing conditions and quantitative evaluation of stability for <br />existing and projected conditions. Chapter 5.0 presents these conclu- <br />sions and discusses recommendations for further action based on these <br />conclusions. <br />1.3 SUMMARY OF CONCLUSIONS <br />Based on the results of this evaluation as coupled to previous assess- <br />ments, the following conclusions were reached: <br />o Existing Embankment Conditions <br />- The dam consists of (a) an inner section or <br />core of layered soils consisting of silty and <br />clayey sand; and (b) outer section or shells <br />of more coarse material. <br />- The inner section is moderately permeable with <br />coegficient of permeability values of 10-4 and <br />10 cm/sec. The vertical permeability may be <br />nearly equal to or greater than the horizontal <br />permeability, especially in the lower portion <br />of the inner section and near the center of <br />the valley. <br />- The outer shells of the dam have a coefficient <br />of permeability higher than the inner section. <br />The core and shell material have strengths <br />appropriate for the types of materials. No <br />voids or other major discontinuities were <br />observed within the core. <br />1 - A cutoff trench was excavated beneath the dam <br />and backfilled with compacted core material. <br />