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The Marr Mine produced coal from the Sudduth seam with a truck-and-shovel operation. The <br />coal dips to the east and northeast at 68 degrees. The mine plan described the extraction of coal <br />from a triangular cut, 265 feet deep. Kerr Coal Company operated two pits, the 720 Pit and Pit <br />1. Coal extraction from the 720 Pit ceased in 1983 and from Pit 1 in 1993. Annual production <br />over time ranged from a high of 750,000 tons in 1980 to a low of 35,000 tons in 1988. As <br />documented in the Division's November 17, 2008 Proposed Decision and Findings of <br />Compliance document for Bond Release Number SL-04, there are currently 17.0 acres of <br />disturbance remaining at the mine site and 11.7 acres of disturbance remaining at the loadout. <br />In the past, coal was trucked to the Marr loadout facility, south of Walden, where it was <br />stockpiled, crushed, screened, and loaded out. The loadout is located on fill that has placed the <br />surface at 8060 feet. The 100-year flood level is at 8046 feet. A lumber sawmill was located <br />just north of the loadout on higher ground. Sawmill junk and plant wastes appear to have been <br />pushed downslope over the years, forming a bench and a well-defined bluff overlooking the <br />loadout. An irrigation ditch physically separates this encroaching bluff from the main part of the <br />loadout. The lumber sawmill waste was cleaned up by the company in the late summer and early <br />fall of 2001. The area was cleaned, covered, topsoiled, seeded and mulched. A wedge-shaped <br />part of the permit area, measuring 500 feet long by 25 feet wide, lies north of the irrigation ditch <br />at the northwest corner of the permit area. Water for dust suppression activities was pumped <br />from a well with an absolute decree of eight acre-feet per year. <br />The hydrologic balance of the original mine plan area was to be maintained in part by 14 <br />sediment ponds, various drainage ditches and discharge structures. Only seven sediment ponds <br />were constructed because portions of the mine (Pits 2 and 3) were never opened. This runoff <br />containment system appears to be adequately designed and constructed in accordance with <br />Colorado law (34-33-120) and Rule 4.05. Sediment Ponds A and D exceed 20 acre-feet in <br />storage capacity. The emergency spillways for these two ponds were designed and constructed <br />for the 100-year, 24-hour event. Many ponds utilize baffle structures to ensure adequate <br />detention time. With the approval of Technical Revision 19 on January 11, 2000, the Division <br />approved the permanent retention of sediment ponds A, B, D and E. With the approval of the <br />partial Phase II Bond Release SL-02 on June 26, 2001, the Division recommended the removal <br />of sediment ponds F and G. Drainage ditches B-l, 13-2, 1-2,1-3, and N-2 were designed for the <br />100-year, 24-hour event. Certain steeper sections of drainage ditches I-2, N-2, and B-2 are <br />designed with riprap bottoms to minimize the erosive effects of flowing water. <br />Kerr Coal Company's water rights and its water augmentation plan are detailed in Volume 10, <br />Exhibit 25. The augmentation plan lists a total water consumption of 69.46 acre-feet per year. <br />The figure includes 66.9 acre-feet for pond dead storage and 2.56 acre-feet consumed for dust <br />suppression, other industrial usage, and sanitary needs. Kerr Coal Company claims 315.2 acre- <br />feet of water rights for potential mitigation of adverse impacts to surrounding water users. Based <br />upon the data, Kerr Coal Company has adequate water rights to mitigate adverse impacts to <br />neighboring water users. <br />Topsoil and subsoil salvage and replacement were approved to vary among pits and soil types. <br />Information on soil removal and replacement can be found on pages 816-6 to 816-28 and on 816- <br />125 of the permit application. Tables 57aa (Total Soil Averages and Depths by Mine Plan Year) <br />12