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West Pit Fill Inspection Certification <br />On June 10, 2015, 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 4.09.1(1)(c) and Rule 4.09.1(11). At the time of inspection, <br />weather conditions were 60°F and cloudy. <br />Based upon my observations, the regraded fill was observed to be stable and unchanged. The <br />underdrain below the West Pit Fill was not seeping at the time of inspection. No other seeps, <br />slumps or signs of significant erosion were noted on the fill surface. <br />The current water level of the monitoring piezometer was obtained. The water level taken at the <br />time of inspection was 80.8 feet from the ground surface, an increase in water elevation of 0.1 feet <br />from the previous quarterly inspection. <br />I reviewed the monument survey data collected on June 9, 2015. This data was compared to the <br />survey data collected during the previous quarter on March 27, 2015. After review of the June 9, <br />2015 data, the largest indicated vertical displacement from the previous quarter survey was 0.225 <br />feet at the 7250 West Prism. The remaining prisms measured a displacement of 0.041 feet or less. <br />The 7250 West monument prism was missing during the fourth quarter of 2014, and was replaced <br />during the first quarter of 2015. The 7250 West monument prism indicated the largest displacement <br />during this quarter; however the indicated movement is reversed (negative movement) from the <br />previous movement trend. In my opinion, this indicated movement is not related to slope movement, <br />but rather related to the prism replacement. I observed no evidence of slope movement at the time <br />of inspection. The 7250 West area will be monitored closely, and surveying will inspect the prism. <br />Based on the remaining prism data, the displacement of the monuments are not of concern with <br />regard to the stability of the fill. The degree of measured displacement can be caused by normal <br />settlement, survey variation, and monument disturbance from animal traffic, weather etc. During <br />inspection, I observed no evidence of structural weakness, slumps, seeps or other hazardous <br />conditions associated with this fill. The monument survey data is available for review upon request <br />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 West Pit <br />Excess Spoil Fill is observed to be stable, at the time of inspection, and in compliance with CDRMS <br />Rule 4.09.1(1)(c) and Rule 4.09.1 (11) , and Permit C-1981-019. <br />Vic, •- � � `� <br />47031 S <br />*/1,11111111111100/ONAL <br />; �����` <br />