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2.05.4 RECLAMATION PLAN <br />The topographic features at the CEC mine site aze chazacterized by low rolling sand hills <br />on a semi-arid plain. Surface elevations range from 4905 feet to 4775 feet, sloping <br />generally downgradient to the northeast, as shown on the site topographic map presented <br />in Appendix O-1. There has been little or no measurable or observed surface water <br />runoff except during severe thunderstorms when runoff will be accumulated in existing <br />pit areas, runoff control structures, or reclaimed topographic low (depression) areas. <br />There has been no observed surface water discharge from the property. All drainage <br />structures located on site to control surface water runoff have been designed (and <br />certified) by a professional civil engineer. <br />The CEC site is covered with 20 to 40 feet of wind deposited sand (eolian sand). This <br />sand overlies the clay and shale beds of the Laramie Formation (of Cretaceous age). This <br />soil type is highly susceptible to wind erosion, and consequently, ground surface <br />blowouts exist iri several areas on the site. <br />Two soil types of topsand exist locally. The SCS designated Osgood soil series is <br />twenty-eight (28) inches thick and the SCS designated Valent soil series is six (6) inches <br />thick. The soil chazacteristics of each type are summazized in Section 2.04.9 of this <br />document and discussed in detail in the Berg Report, presented in Appendix L-1. <br />• All major disturbed areas on the CEC mine site have been or will be returned to their <br />Approximate Original Contour (AOC), including A and B-Pits which have been and are <br />presently permitted for ash and mine waste rock (herein abbreviated "A/MWR")disposal. <br />[See Appendix R for technical data relative to the ash and mine waste rock, and for <br />revisions to the coaUAIMWR supply.) Both pits were previously reclaimed by CEC to <br />five (5) feet above the re-established local ground water table and have a combined <br />capacity for about 15 years of A/MWR disposal by Coors. Both A- and B-Pits were <br />"grandfathered" under the State of Colorado Department of Public Health and <br />Environment (CDPHE) Subtitle D regulations governing future ash disposal, dated <br />November 30, 1995 (revised), titled the "Regulations Pertaining to Solid Waste Disposal <br />Sites and Facilities, 6 CCR 1007-2," and are regulated by both the CDPHE and the Weld <br />County Department of Health (WCDH). <br />CEC compiles an annual summary of the activities related to ash disposal at the CEC <br />mine site. This summary includes; source(s) of ash, quantities of ash received for <br />disposal, ash transportation and disposal activities, and maps indicating the progress of <br />disposaUreclamation activities. This summary information can be found in the Annual <br />Hydrology and Reclamation Report (AHR report). Monthly documentation of ash source <br />and quantity, including any disposal issues and how they were resolved, is maintained at <br />the mine site. Here too are found maps which indicate ash depths and aerial extent of <br />disposal activity. <br />CEC also performs an annual evaluation of the ash disposed at the site. At a minimum <br />one (1) representative sample each of fly ash and bottom ash is collected from the boilers <br />at the Trigen power plant (Golden). These samples are laboratory analyzed according to <br />II3 10/00 <br />