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's <br />thees`static factor .of, safety, decreases„;:,z <br />existing ver`"sus"1.S acceptable). <br />the <br />�Sncrease the. -factor' of safety, again <br />fa`ilure'+,for. future conditions: <br />1-6 <br />1.4 SUMMARY OF RECOMMENDATIONS <br />To improve the integrity of this structure, remedial measures are <br />recommended to control or stop the seepage and improve the embankment <br />slope stability. Regarding -seepage;' control is most likely the' -least <br />costl remedial _a a °� <br />y; pproich,�.with the..?higtie tentia for success. <br />Properly constructed downstream drains and other collection systems can <br />accomplish this result. The seepage will increase however, and a <br />collection pump back system will be required for the life of the <br />facility. <br />Stopping the seepage can potentially be accomplished .by lining'the pond; <br />installing a slurry wall cutoff beneath the dam, grouting :or other <br />mechanisms discussed in previous D'Appolonia reports. Although success <br />may be achieved at low cost with some schemes, the risk exists that the <br />cost will be large or that success will be limited. <br />Increasing the embankment stability can be accomplished by,.constructing i <br />an earth berm against the downstream toe. The•.weight ofIthe berm will <br />act against- >,seepage, forces"and" increase "the'dam stability. A .gravel' <br />drain beneath the berm will control seepage tending to rise to the <br />ground surface in this area. In addition, relief wells installed below <br />the drain will control or relieve high pressures which may exist in the <br />alluvial soils and upper bedrock in the toe area. Z tChe4embankment=is <br />:4 t <br />'�.. V "1'1 <br />'raised ate -some: future, time,'"'stab'ilitl7 can='also be"_increased by,.con <br />ure <br />