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West Pit Fill Inspection Certification <br />On May 25, 2007, I inspected the area in which the West Pit Excess Spoil Fill is being <br />constructed. The purpose of this inspection was to observe the surface rock drain that <br />borders the 3H:1V Excess Fill Slope, inspect the areas dumped to final grade below the 7,400 <br />dump elevation, inspect the revegetation on the fill surface, inspect the fill for areas of water <br />seepage or surface drainage, inspect the final grade slopes below the 7,300 elevation of the <br />Excess Fill Slope, and satisfy the requirements of CDMG Rule 4.09.10 (1a) and Rule 4.09.1 <br />(1 b). <br />During the inspection, it was observed that the condition of the fill was good and that no seeps <br />or springs were noted. The collection ditches at the 6,950, 7,050, and 7,150 elevations all <br />were in relatively good shape. The ditch at the 7,250 elevation needs to be completed to the <br />west end of the fill. A small amount of water was evident coming from the toe of the <br />underdrains. All three of the completed terrace ditches showed recent evidence of flow <br />following spring snowmelt. No erosion problems with the ditches were noted. <br />In addition, I reviewed the monument survey data. These data indicate that the elevations of <br />most of the monuments have not significantly changed (typically less than 0.05 feet of <br />elevation change) with the most movement noted in the 7250 East and West monuments (a <br />decrease of 0.06 feet). Based on these data, the total displacement of the monuments is not <br />of concern with regard to the stability of the dump. There was also no evidence of structural <br />weakness or other hazardous conditions associated with this dump. These monument survey <br />data are available for review upon request at the Colowyo Mine site. <br />I am a Registered Professional Engineer in the State of Colorado and a representative of <br />Environmental Solutions, Inc, P. O. Box 2996, Cheyenne, Wyoming. Being familiar with the <br />Colowyo operation and the coal program permitting process in Colorado, the construction <br />activities related to the West Pit Excess Spoil Fill are in conformance, to the best of my <br />knowledge and experience, as specified in pages I a-2 through I a-4, Exhibit 19 I b and other <br />applicable requirements of the approved permit documents, a portion of CDMG Permit C-81- <br />019. .........._ <br />~~O~,ppO I' l C' p~~~i <br />~ ~ ......, F ~ <br />O :~ G. Pfrf~~yaP~O <br />32257 ~ <br />~o •;~6~b1~7• ~' <br />~~~~ S`s~ONAI•E'~ad <br />(plG ~0'7 <br />xc: Mr. Kurtis Blunt, Colowyo Coal Company, L.P. <br />cf 17.15.1 2005 <br />cf 24.20 (West Pit) <br />