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1 <br />r ? <br />West Pit Fill Inspection Certification <br />On October 20, 2009 and again on December 14, 2009, 1 inspected the area in which the West Pit <br />is Excess Spoil Fill is being constructed. The purpose of this inspection was to observe the surface <br />rock drain that borders the 3H:1V Excess Fill Slope, inspect the areas dumped to final grade below <br />the 7,400 dump elevation, inspect the revegetation on the fill surface, inspect the fill for areas of <br />water 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 (1 b). <br />During the inspection, it was observed that the condition of the fill was unchanged and stable. All <br />portions of the fill were visible. A small flow of about two gallons per minute is evident from the toe <br />of the underdrain. A second small flow of less than two gallons per minute was noted near the point <br />where the toe of the fill intersects the access road for the West Pit Pond. This flow was primarily a <br />result of surface water runoff but is probably supported by some contribution from the toe of the <br />underdrain. No erosion problems were noted. No other seeps or springs were noted. <br />In addition, I reviewed the monument survey data collected October 7, 2009. These data indicate <br />that the elevations of most of the monuments have not significantly changed (typically less than <br />0.05 feet of elevation change per calendar quarter). The most change was recorded at the 7150 <br />West monument. This site registered a decrease of 0.12 feet. Based on these data, the total <br />displacement of the monument is not of concern with regard to the stability of the dump. There was <br />also no evidence of structural weakness or other hazardous conditions associated with this dump. <br />These monument survey data are available for review upon request at the Colowyo Mine site. <br />I am a Licensed 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 activities <br />• related to the West Pit Excess Spoil Fill are in conformance, to the best of my knowledge and <br />experience, as specified in pages I a-2 through I a-4, Exhibit 19 1 b and other applicable <br />requirements of the approved permit documents, a portion of CDMG Permit C-81-019. <br />No- <br />,%%N Pp 0 L / ?F ?,A <br />O? ••? ?• Pfl?: S? <br />V.- 32257 <br />79p OF <br />j1 <br />:1_1\ <br />•••.••• .r? <br />P.E. No. 32257 <br />/ Zl 14'/09 <br />DA FE <br />xc: Mr. Kurtis Blunt <br />. cf 17.15.1 <br />cf 24.20 (West Pit)