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Mr. Lee Sampson <br />September 22, 2022 <br />Page 5 <br /> <br />Agapito Associates, Inc. <br />As the spoil has been end dumped from the crest of the fill, a height of greater than 100 ft, the <br />natural sorting extends entirely across the valley floor, which would encompass any lateral drains <br />present in the valley. This is shown in Figure 4, a photograph taken of the north end of the dump <br />during the September 13, 2022, site inspection. Previous photos taken by the mine, see Figure 5, <br />indicate that the natural sorting has taken place along the entire length of the valley fill in the draw. <br /> <br />The unsorted spoil at the mine has previously been estimated to have the following gradational <br />characteristics2: <br /> <br /> Cobbles and boulders 50% <br /> Gravel 28% <br /> Sand 2% <br /> Fines (No. 200 sieve) 20% <br />  <br />On this basis, it is expected that above the base of the dump, the composition of the spoil is <br />dominated by gravel, sand, and fines. This is consistent with visual and tactile observations made <br />during the September 13, 2022, site inspection. <br /> <br /> <br /> <br />Figure 4. Photograph Taken during September 13, 2022, Site Visit Showing Natural Sorting <br />from End Dumping in Little Collom Draw <br /> <br />2 CTL/Thompson, Inc. (1992a), “Underdrain Filter Requirements, West Pit and Section 16 Pit Excess Spoil Fills,” <br />Letter Report prepared by CTL/Thompson, Inc., Job No. 18,683, for Colowyo Coal Company, Meeker, CO, April <br />27.