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knocking down the pit highwalls to a 4H:1V slope. A thirty foot depression will <br />be left. A drainage corridor will be constructed at the south end of the pit to <br />properly drain this depression. This drainage corridor will daylight to an <br />existing arroyo which ultimately reaches Bolton Draw. The corridor will be <br />approximately 500 feet long and have 4H:lV side slopes. <br />Final contours of the pit are shown on Figure lo. Cross Sections are provided <br />on Figure 2. The north-south drainage split will be at Station -4+00. During <br />revegetation all drainage to the north will pass through existing sedimentation <br />Pond 001. Drainage to the south will be contained by a newly constructed <br />pond in the drainage corridor. Sizing calculations and a stage volume analysis <br />for this pond are shown on in Appendix Q. A temporary drainage diversion <br />ditch will be installed on the west side of the pit. This ditch will keep <br />undisturbed runoff from entering the reclaimed area. All ponds and diversions <br />will 6e removed following appropriate bond release procedures. <br />WFC currently has a 64,000 cy topsoil stockpile. Approximately 8,000 cy of <br />additional material will be salvaged during drainage corridor construction and <br />reduction of highwalls. Topsoil will be stripped from the Manburn soil series, <br />stripping depth 1.25 ft. The 72,000 cy of available topsoil will provide an <br />average cover of 0.5 ft over the 81 acres to be topsoiled. <br />Seeding will be accomplished in the fall or spring depending upon completion <br />of backfilling, grading and topsoiling. The seed mix to be used is presented in <br />Exhibit 3. Agronomic practices may include contour furrowing and pitting. <br />WFC plans to mulch at a rate of 2 tons/acre straw or hay or its equivalent of <br />hydromulch. <br />The loadout site in Walden is an industrial site. An estimated 1,550 cy of coal <br />will be picked up and hauled to and buried in the Canadian Strip pit. No <br />further work is required for this site. <br />• 11613 (Revised 04/13/90) <br />