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Regulations for Hard Rock, Metal and Designated Mining Operations section 1.5.3 and section <br />1.9.1. <br />TR -5 field construction was under the direction of Mr. Erich Rauber (PE) and the supervision of <br />Mr. George M.L. Robison (CPG -5022). The following summarizes implemented construction <br />activities and field modification from the proposed design. <br />1. Wildcat commits to installing a MSHA compliant berm on the road above the Chief <br />portal leading to the Incas mine; <br />2. Wildcat commits to installing a MSHA compliant door to the 66 inch Chief Manway; <br />3. Wildcat requests the approval to change the stabilized scarp above the Chief Portal from <br />vegetation to scree on 80% of the slope and to provide documentation the remaining <br />slope has been stabilized using vegetation and appropriate erosion control methods; <br />4. Slope stabilization construction QA/QC included the following: <br />a. An additional row of gravity blocks were added to the toe of the slope to <br />accommodate the unanticipated deeper depth required to install the 66 inch <br />manway culvert. <br />b. The toe of the slope gravity blocks were installed on a solid foundation (coarse <br />rock >6 inches). <br />c. Initial excavation determined the material characteristics of the backfilled <br />material did not compare to the geotechnical test results in the original plan. The <br />original design determined the backfill material would be homogeneous capable <br />of compacting to engineering specifications. (See As -Built Completion Report, <br />Wildcat -June 28, 2016) During excavation 50% of backfill material consisted of <br />rocks greater than 6 inches in diameter. Because of the encountered material <br />characterization, backfill material could not be compacted or tested per the <br />approved plan. The back fill material above the Chief portal (manway) was <br />placed in 8 to 12 inch lifts and compacted using an excavator. Backfill <br />construction activities continued to a height represented by the gravity blocks <br />located on the upper part of the back fill (See Attached photo). The upper portion <br />of the backfill slope could not be accessed because it was beyond the reach of the <br />excavator and due to the fact a stable bench to access the upper portion of the <br />backfill was not feasible to construct. To provide upper slope stability, rock (>6 <br />inch) was placed. It is important to note the back fill material consists of coarse <br />rock and is free draining thus negating the need to install sub drains. It is also <br />important to note the slope is constructed to an angle that does not impinge on <br />Little Deadwood Gulch drainage while providing the maximum stability of the <br />backfill material above the portal while providing the necessary stability to <br />Wildcat Mining Corporation <br />M-1981-185 <br />Technical Revision 05.1 <br />Page 2 of 3 <br />