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I <br />1-5 <br />- The three flow mechanisms combine beneath the <br />downstream shell of the dam downgradient from <br />the embankment cutoff. From there, the single <br />flow system moves with little head loss to <br />exit through natural soils in areas downstream <br />of the embankment toe. Seepage beneath the <br />downstream shell is primarily in the fractured <br />rock or in open work gravels in the allu- <br />vium. The foundation soils and rock beneath <br />the downstream shell of the dam provide a <br />preferred flow path compared to the con- <br />structed chimney and blanket drain in the <br />embankment and consequently carry the majority <br />1 of the seepage. <br />Seepage in the potential fault may contribute <br />to anomalous, differential flow conditions at <br />adjacent points in areas downstream of the <br />dam. <br />o Seepage and Flow Path Evaluations <br />Flow into fractured rock and open work gravels <br />beneath the dam, and subsequent uncontrolled <br />exit downstream are not considered prudent dam <br />performance conditions. <br />- No evidencetiof:agiassivexmovement `of"soils from <br />neath the: downs treamrtoe,-was-observed,�.but,_a <br />boil (area of upward .seepage. -.flow causing <br />suspensions ofv soil},partidles)94through ,natural <br />alluvial materials".was noted downstream of the <br />dam toe. <br />As the pond is raised, seepage amounts will <br />increase, thereby increasing the concerns <br />related to uncontrolled seepage. <br />- .CoonLrol�or�ssignificani, reductiogrof.. seepeag <br />� �`:�'.isjcons3d�'ered�prudent�and�%s�ecommerided ,;;,:'..>,'_; <br />o Slope Stability Evaluations <br />=a: The,�-fmacttt.,or of�safety'`A_gWU6't`slope'_failure for <br />�w�l <br />As the pond level is increased, <br />