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J. J. Dudash - 2 - August 8, 1997 <br />Volume VII, Tab 3 presents a discussion of the stability of the reclaimed fill slopes. The <br />benches shown on Sections A-A and B-B were assumed to be reclaimed and analyzed <br />for stability and found to be have safety factors greater than 1.3. The change in the <br />bench configuration should not affect the stability analysis since the excavated material <br />was simply placed in a slightly different location than was permitted. There is still a <br />bench to backfill and the material can be placed as recommended in Volume VII, Tab 3. <br />The maximum cut height of the portal bench occurs immediately above the proposed <br />portals on both the permitted and as-constructed benches. The permitted bench was <br />cut from elevation 7050 to 6890 which is 160 vertical feet. The as~onstructed bench <br />was cut from elevation 7050 to 6880 which is 170 vertical feet. <br />The maximum fill for the permitted coal bench was about 130 vertical feet (6830 - <br />6700). The maximum fill for the as~onstructed bench is about 170 vertical feet (6870- <br />6700). The slope of the fill on the as-constructed bench is 2h:1v or slightly greater. <br />Maxim's original Geotechnical Engineering study (page 14) states that for slopes where <br />some risk of erosion, creep and shallow slope failures can be accommodated, the <br />overall slope of fills can be 2h:1 v. <br />The cut and fill slopes of the as-built bench conform to the recommendations presented <br />in Volume VII. Cut slopes were excavated at 1.5h:1 v and fill slopes were placed at <br />2h:1 v. <br />We have arranged to have the property flown as early as August 8'^ so we can begin <br />the preparation of a technical revision to incorporate the above changes into the permit. <br />Please call if you have any questions. <br />Sincerely, <br />Jim Stover, P.E. <br />Consulting Engineer <br />cc: Wm. A Bear, Jr. <br />