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ArCOM <br />Technical Memorandum— 3 Dam Reslope Project <br />October 5, 2017 <br />Page 3 <br />x{ <br />Photo 2 — View of stepback area (for placement of excess fill), looking southwest (June 8). <br />June 14. 2017 <br />Regrading/trimming of the downstream slope of the original 3 Dam was in progress, using two <br />Caterpillar D8T dozers, one with GPS elevation control on the blade. Both dozers were working from <br />toe to crest each pass, pushing excess material uphill and across the dam crest to form a stockpile <br />and to achieve a 4H:1V final grade of the downstream slope. Limited placement/compaction of the <br />excess fill in the 3 Dam stepback area started in the last two days and was completed using a third <br />D8T dozer (spreading the tailings in lifts and performing track compaction using the weight of the <br />machine). <br />The typical cut was about 0.5 feet at the toe and 4 feet at the crest. The exposed material at the base <br />of the cut was the same or similar as observed on June 8. The operators left intact zones of several <br />feet of tailings around piezometers that exist in the slope. That material will be trimmed to grade once <br />the standpipes to the instruments are lowered. <br />A total of approximately 520 If of the downstream slope of 3Dam had been regraded by day's end. <br />