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West Pit Fill Inspection Certification <br />On June 30, 2008, 1 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. All portions of <br />the fill were visible. The collection ditches at the 6,950, 7,050, and 7,150 elevations all were <br />in relatively good shape. The ditch at the 7,250 elevation needs to be completed to the west <br />end of the fill. All three of the completed terrace ditches showed some evidence of flow <br />following recent snowmelts. No erosion problems with the ditches were noted. Only a very <br />minimal flow of less than 5 gpm is evident from the toe of the underdrain. No erosion <br />problems were noted. A small seep of about 2 gallons per minute was noted near the point <br />where the toe of the fill intersects the access road for the West Pit Pond. No other seeps or <br />springs were noted. <br />In addition, I reviewed the monument survey data collected June 9, 2008. These data indicate <br />that the elevations of most of the monuments have not significantly changed (typically less <br />than 0.05 feet of elevation change per calendar quarter). The 7050 West monument <br />registered the most change. As noted in the prior report, the March, 2008 reading of this point <br />appeared to be in error with a 0.46 feet upward movement. This is confirmed with the June <br />reading of this point. Discounting this data point, the most vertical displacement was seen in <br />the 7250 East monument with a decrease of 0.11 feet. Based on these data, the total <br />displacement of the monuments is not of concern with regard to the stability of the dump. <br />There was also no evidence of structural weakness or other hazardous conditions associated <br />with this dump. These monument survey data are available for review upon request at the <br />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 <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 1 b and other <br />applicable requirements of the approved permit documents, a portion of CDMG Permit C-81- <br />019. ...11111218.._ <br />Q? ........ e <br />?. o <br />y; <br />Z 32257 Z <br />O •. <br />???isS?ONAt• ?'???? <br /> <br />xc: Mr. Kurtis Blunt, Colowyo Coal Compar?y;Et' 32257 <br />cf 17.15. -711108 <br />cf 24.20 (West Pit)