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8060 feet. The 100-yeaz flood level is at 8046 feet. A lumber sawmill was located just north of the tipple azea on higher ground. Sawmill junk and plant wastes appeaz to have been pushed downslope over the years, forming a bench and awell-defined bluff overlooking the tipple area. An irrigation ditch physically separates this encroaching bluff from the main part of the tipple azea. The lumber sawmill waste was cleaned up by the company in the late summer and early fall of 2001. The area was cleaned, covered, topsoiled, seeded and mulched. Awedge-shaped part of the permit area, measuring 500 feet long by 25 feet wide, lies north of the irrigation ditch at the northwest corner of the pemut azea. Water for dust suppression activities was pumped from a well with an absolute decree of eight acre-feet per yeaz. The hydrologic balance of the original mine plan area was to be maintained in part by 14 sediment ponds, various drainage ditches and discharge structures. Only seven sediment ponds were constructed, as portions of the mine (Pits 2 and 3) were never opened. This runoff containment system appears to be adequately designed and constructed in accordance with Colorado law, 34-33- 12Q and Rule 4.05. Sediment Ponds A and D exceed 20 acre-feet in storage capacity. The emergency spillways for these two ponds were designed and constructed for 100-year, 24-hour events. Many ponds utilize ballle structures to ensure adequate detention time. With the approval of Technical Revision 19 on 11 January 2000, the Division approved the permanent retention of sediment ponds A, B, D and E. With the approval of the partial Phase II Bond Release SL-02 on 26 June 2001, the Division recommended the removal of sediment ponds F and G. Drainage ditches B-l, B-2, I-2, I-3, and N-2 were designed for 100-yeaz, 24-hour events. Certain steeper sections of drainage ditches I-2, N-2, and B-2 are designed with riprap bottoms to minimize the erosive effects of flowing water. Kerr Coal Company water rights and its water augmentation plan are detailed in Volume 10, Exhibit 25. The Augmentation Plan lists a total water consumption of 69.46 acre-feet per yeaz. The figure includes 66.9 acre-feet for pond dead storage and 2.56 acre-feet consumed for dust suppression, other industrial usage, and sanitary needs. Kerr Coal claims 315.2 acre-feet of water rights for potential mitigation of adverse impacts to surrounding water users. Based upon the data, Kerr Coal has adequate water rights to mitigate adverse impacts to neighboring water users. Topsoil and subsoil salvage and replacement were approved to vary among pits and soil types. Information on soil removal and replacement can be found on pages 816-6 to 816-28 and on 816-125 of the permit application. Tables 57aa (Total Soil Averages and Depths by Mine Plan Yeaz) and 59a (Soil Redistribution Plan) contain information on soil depths and volumes that were to be removed and replaced throughout the permit term. Soils in the 720 Pit were salvaged prior to promulgation of the Colorado Surface Coal Mining Reclamation Act, and six inches of material, regazdless of suitability, were salvaged. In general, six inches of topsoil was salvaged from Pit 1 and was required to be replaced (page 816-126). The Division dug several pits during the partial Phase II Bond Release inspection (for SL-O1) on 22 May 2001 and came up with an average topsoil depth of 7.5 inches. Topsoil at the tipple was not extensively salvaged. The topsoil that was salvaged has been replaced and appears to be adequate to support the growth of vegetation. KCC also transported topsoil that was to be used for pond reclamation at the mine site to supplement the topsoil at the loadout. The revegetation plan called for drill seeding an annual cover/mulch crop of Russell oats in the Man• Mine Permit Renewa105 17 March 2006 _l2_