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Page 10 of 10 <br />• (TR -45) Effective Shear Strength Parameters (1 set) based on Consolidated - Undrained (CU) <br />testing <br />Coal Mine Waste <br />Gob Pile #2 <br />• (TR -42) Gradation & Atterberg Limits (3); Specific Gravity (4); Standard Proctor (3) <br />• (TR -42) Unconsolidated - Undrained (UU) Shear Strength (5) <br />• (TR -42) Effective Shear Strength Parameters (3 sets) based on Consolidated - Undrained (CU) <br />testing <br />Gob Pile #4 <br />• (TR -44) Unconsolidated - Undrained (UU) Shear Strength (6 new) <br />• (TR -64) Effective Shear Strength Parameters (3) revised from TR -42 values; evaluated <br />sensitivity at 4' = 30, 32 and 34 degrees <br />Historically, the coal mine waste generated by BRL's prep plant has contained a significant <br />percentage of fine material, which in turn results in the waste product having an extremely high <br />moisture content. On occasion the material has been over - saturated, with a soupy consistency. <br />It has been the practice of Bowie Resources, LLC, to dump and temporarily stockpile this waste <br />within the footprint of an approved gob pile. This allows some of the excess moisture to drain <br />away, by gravity. Often the material is worked, and reworked, by excavators which turn the <br />material over, move it from place to place, to free up more of the moisture and expose it to the <br />air. Ultimately, BRL blends the waste with dry coverfill (native soil), that has been salvaged and <br />stockpiled separately, in order to obtain a product with a moisture content that approaches the <br />range where compaction can successfully be achieved. <br />Aside from the ongoing compaction (moisture- density) testing that is conducted on the mixed <br />material, there appears to have been no laboratory analysis of the strength parameters of the <br />coal mine waste / coverfill blend. This is an issue that should be addressed, and remedied, if <br />necessary. <br />