2009-06-29_REPORT - C1981019 (2)

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West Pit Fill Inspection Certification On June 19, 2009, 1 inspected the area in which the West Pit Excess Spoil Fill is being constructed. The purpose of this inspection was to observe the surface rock drain that borders the 3H:1V Excess Fill Slope, inspect the areas dumped to final grade below the 7,400 dump elevation, inspect the revegetation on the fill surface, inspect the fill for areas of water seepage or surface drainage, inspect the final grade slopes below the 7,300 elevation of the Excess Fill Slope, and satisfy the requirements of CDMG Rule 4.09.10 (1a) and Rule 4.09.1 (1b). During the inspection, it was observed that the condition of the fill was unchanged and stable. All portions of the fill were visible. The collection ditches at the 6,950, 7,050, and 7,150 elevations all were in relatively good shape. The ditch at the 7,250 elevation needs to be completed to the west end of the fill. A small flow of about two gallons per minute is evident from the toe of the underdrain. A second small flow of less than two gallons per minute was rioted near the point where the toe of the fill intersects the access road for the West Pit Pond. This flow was primarily a result of surface water runoff but is probably supported by some contribution from the toe of the underdrain. No erosion problems were noted. No other seeps or springs were noted. In addition, I reviewed the monument survey data collected June 18, 2009. These data indicate that the elevations of most of the monuments have not significantly changed (typically less than 0.05 feet of elevation change per calendar quarter). The 7250 West monument registered the most change. The vertical displacement was an increase of 0.10 feet. Based on these data, the total displacement of the monuments is not of concern with regard to the stability of the dump. There was also no evidence of structural weakness or other hazardous conditions associated with this dump. These monument survey data are available for review upon request at the Colowyo Mine site. I am a Licensed Professional Engineer in the State of Colorado and a representative of Environmental Solutions, Inc, P. O. Box 2996, Cheyenne, Wyoming. Being familiar with the Colowyo operation and the coal program permitting process in Colorado, the construction activities related to the West Pit Excess Spoil Fill are in conformance, to the best of my knowledge and experience, as specified in pages I a-2 through I a-4, Exhibit 19 1 b and other applicable requirements of the approved permit documents, a portion of CDMG Permit C-81-019. z ? ? S l V ; y4`? ??o ? D 32257// ?'o•:6fZ isS/ONAL E? P.E. No. 32257 e/zo% VA it xc: Mr. Kurtis Blunt cf 17.15.1 cf 24.20 (West Pit)