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<br />VIII. Coal Mine Waste Banks <br />There are no coal mine waste banks at this site. (4.10) <br />IX. Coal Mine Waste <br />1. There is no coal mine waste at this site. (4.11) <br />X. Backfilling and Grading <br />1. Information on backfilling and grading is found in Sections 2.05.3 and 2.05.4, <br />and on Maps ]0, 11,12, 13, and 16, of the permit application. There were two <br />sections of the permit azea where backfilling and grading operations were <br />concentrated: The Middle Creek Portal Pit and the Mine No. 3 surface mine. <br />CYCC proposed to backfill and grade the Middle Creek Portal Pit area. <br />Sufficient material was available to achieve the designed post-mining topography <br />from two existing overbwden stockpiles and previously distwbed ground <br />adjacent to County Road No. 179 above the portal pit area. In preparation for <br />final reclamation, slopes were graded from Sh:ly, to gently sloping. The <br />proposed slopes should be geotechnically stable and will achieve the approved <br />post-mining topography. In addition, the final topographic configuration did not <br />present any difficulties for topsoil redistribution or revegetation. The estimated <br />time for backfilling the portal pit was eighteen weeks, weather conditions <br />permitting. Backfilling and grading in the portal pit area completed during the <br />1984 construction season. <br />At Mine No. 3 a total of 1,033,000 bank cubic yards (BCY) of overbwden were <br />removed. Of this overbwden material, 250,000 BCY was temporarily stockpiled <br />for backfilling the final cut. The remaining overbwden material was backfilled <br />into the swface pit within 180 days afrer coal removal. Final reclaimed slope <br />configurations were graded to achieve adequate drainage, with the last area <br />topsoiled dwing 1986. The proposed post-mining topography appeazs <br />geotechnically stable and should present no problems for topsoiling and <br />revegetation. <br />The temporary overbwden stockpile did not exceed 50 feet in height, had <br />1.Sh:ly side slopes, and was constructed in 8 foot lifrs to provide for compaction <br />and to increase geotechnical stability. Swface runoff was intercepted by the <br />proposed pit above the stockpile location. Because the upper slope drainage was <br />diverted away from the stockpile and the observed 1.25h:1v slopes in dragline <br />spoils have had no failwes, the designed temporary overbwden stockpile was a <br />stable configwation. This stockpile was used for final backfilling and grading at <br />the end of the anticipated two year mine life. <br />No acid forming or toxic forming materials have been encountered within the <br />proposed permit area; therefore, no special handling will be required. <br />17 <br />