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2.05.3 <br />The fill material shall be free of sod, large roots, other large vegetation <br />matter, and frozen soil, and in no case shall coal -processing waste be used <br />in embankment construction. <br />The placing and spreading of fill material shall be started at the lowest point <br />of the foundation. Materials will be spread in layers approximately 12 inches <br />deep, and such lifts made uniformly over long stretches and for the full width <br />of embankment. Each lift will be moistened or dried to a uniform moisture <br />content suitable for maximum compaction. Hauling equipment will be routed <br />both ways over the fill and routing varied sufficiently to achieve uniform <br />compaction. Compaction will be carried to the edge of the fills so that the <br />final slopes are firm. <br />The embankment shall be constructed so the design height is achieved at all <br />times, including the period after settlement. <br />The combined upstream and downstream side slopes of the settled embankment <br />shall not be steeper than 5h:1 v, with neither slope steeper than 2h:1 v. The gob <br />pile sediment pond has a combined upstream and downstream side slopes of <br />4h:1 v. Because the combined slopes are steeper than 5h:1 v a stability analysis <br />was performed to verify stability. The stability analysis is presented in Volume <br />IV, Section 4.3.3. <br />Faces of the embankments including the surrounding areas disturbed will be <br />vegetated to enhance stability. The minimum top width of the embankments for <br />all four ponds is not less than the quotient of (H+35)/5 where H, in feet, is the <br />height of the embankments as measured from the upstream toe of the <br />embankment. The height of the embankments of all four ponds is less than 10 <br />feet in vertical height measured from the bottom of the channel to the bottom of <br />the spillway. Anti -seep collars will be installed to control seepage along conduits <br />that extend through the embankment. <br />(ii)(C) Operations and maintenance requirements for ponds B, C, J, K, F and the gob <br />pile pond are the same. The sediment ponds must be dewatered if they contain <br />water above the maximum sediment level. Pond C must be dewatered between <br />each mine discharge event to assure the pond maintains the capacity to contain <br />the 10 -year, 24-hour precipitation event. Unless captured in priority, the State <br />Engineers current policy requires that all impounded water be released to the <br />stream system within a maximum of 72 hours after impoundment. Dewatering <br />events will occur within 72 hours after the storm event or mine discharge which <br />caused the water accumulation. Sediment must be removed from the <br />TR -87 2.05-40- 07/14 <br />