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• Photograph 27 shows the completion of the head of the underdrain system. A <br />cross section showing rock size and distribution in the head of the underdrain system is <br />shown in photograph 28. Note hard hat for scale in lower center of picture. <br />Construction at the Mid-Section of the Underdrain <br />An access ramp was constructed to the mid-section of the underdrain to avoid up <br />hill pushing from the toe area and excessively long dozer pushes from the head of <br />underdrain area. Photograph 29 shows a dozer completing the mid-section of the <br />underdrain system. <br />Concurrent with construction of the head and mid-section of the underdrain, access was <br />cut with a dozer to haul in three inch crushed sandstone for the filter at the toe. Photograph 30 <br />shows the access to the toe and photograph 31 shows the crushed sandstone for the filter. <br />The design for the filter indicated a two foot thick filter. The as-built filter was three <br />feet thick and extended outside the controlled underdrain. Photograph 32 shows the filter in <br />place. <br />The underdrain was essentially complete on November 17. Photographs 33 through 36 <br />show a panorama of the underdrain system including the filter at the toe. <br />• A shove] was moved into the boxcut area, replacing front end loader operations, the night <br />of November 17. Weathered material near outcrop was hauled around the perimeter of the fill <br />area to form a ramp system to access high dumps that would later cover the underdrain system <br />with well sorted competent rock. <br />While constructing the ramp system dozers were used to cut trenches at the coal outcrop <br />to better define mining limits and limits for access ramps. The trenching operations indicated <br />the controlled underdrain should be extended an additional 100 feet westward to tie into the coal <br />seam at the mining limit. Additional rock was sorted from the rock crusher operation and <br />hauled in to complete the underdrain system. <br />The underdrain was completed on November 25, 1992. <br />The professional engineers certification for the controlled placement of the underdrain <br />follows. <br />• <br />Section 2 -page 4 <br />