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West Pit Fill Inspection Certification <br />On June 24, 2014, 1 inspected the area in which the West Pit Excess Spoil Fill was constructed. <br />The purpose of this inspection was to observe the surface rock drain that borders the 3H:1 V Excess <br />Fill Slope, inspect the areas dumped to final grade, inspect the revegetation on the fill surface, <br />inspect the fill for areas of water seepage or surface drainage, inspect the final grade slopes, and <br />satisfy the requirements of CDRMS Rule 4.09.10 (1a) and Rule 4.09.1 (1b). At the time of <br />inspection, weather conditions were 80 °F and sunny. <br />Based upon my observations, the regraded fill was observed to be stable and unchanged. The <br />underdrain below the West Pit Fill was seeping at the time of inspection. No seeps, slumps or signs <br />of significant erosion were noted on the fill surface. <br />The West Pit Fill area is complete to PMT design. The West Pit fill area that was regraded in 2013 <br />was topsoiled and seeded during 4th quarter 2013, with three contour furrows placed on the west <br />bank of the active reclamation, and two contour furrows on the east bank of active reclamation. <br />The current water level of the monitoring piezometer was obtained. The water level taken at the <br />time of inspection was 84.2' from the ground surface, a decrease of 0.4 feet from the previous <br />quarterly inspection. <br />I reviewed the monument survey data collected on June 23rd 2014. This data was compared to the <br />survey data collected during the prior quarter on March 14th, 2014. After review of the June 23rd <br />2014 data, the largest displacement from last quarters survey was +0.139 feet at the 7250 West <br />monument, with the remaining monument data deviating less than 0.014 feet. The 7250 West <br />monument had a damaged prism that was replaced this quarter. The 7250 West deviation last <br />quarter was - 0.167', whereas this quarter the deviation was +0.139'. The deviation from this <br />quarterly inspection compared to the March 16th, 2012 inspection was 0.118', which is less than the <br />deviation between this quarter and last quarter. In my opinion, this confirms that the deviation was <br />likely caused by the damaged prism. <br />Based on this data, the total displacement of the monuments are not of concern with regard to the <br />stability of the fill. The degree of deviation can be caused by normal settlement, survey variation, <br />and monument disturbance from animal traffic, weather etc. During inspection, I observed no <br />evidence of structural weakness, slumps, seeps or other hazardous conditions associated with this <br />fill. The monument survey data is available for review upon request at the Colowyo Mine site. <br />I am a Registered Professional Engineer in the State of Colorado. Being familiar with the Colowyo <br />operation, and relying on the information provided to me by Colowyo Personnel, the construction <br />activities related to the West Pit Excess Spoil Fill are in conformance, to the best of my knowledge <br />and 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 CDRMS Permit C -81 -019. <br />�.,see&.�C� <br />_ 47031 _ <br />