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ASCOM <br />Technical Memorandum — 3 Dam Reslope Project <br />October 5, 2017 <br />Page 5 <br />June 27. 2017 <br />Regrading/trimming of the downstream slope of the original 3 Dam was in progress using two <br />Caterpillar DST dozers, one with GPS elevation control on the blade. The dozer without GPS was <br />rough -cutting to about 1 foot above finished grade, and the dozer with GPS was doing final trimming. <br />The typical cut was about 1 to 2 feet at the toe and 8 feet at the crest. The exposed material at the <br />base of the cut was mostly yellowish -tan, fine to coarse, silty sand tailings. with little fine gravel and <br />trace medium to coarse gravel -sized pieces and occasional cobble -sized rock fragments There <br />were also occasional pockets of reddish -brown or light grey, clayey silt tailings (possible slimes) of <br />generally medium stiff to stiff consistency. <br />Placement/compaction of the excess fill in the 3 Dam stepback area continued, using a third DST <br />dozer (spreading the tailings in lifts and performing track compaction using the weight of the <br />machine). <br />The operators left intact zones of several feet of tailings around piezometers that exist in the slope <br />That material will be trimmed to grade once the standpipes to the instruments are lowered. <br />Approximately 550 If of the downstream slope of 3Dam remains to be regraded <br />r .� <br />Photo 5 — View of instrument on regraded slope (to be lowered). Looking north on June 27. <br />