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West Pit Fill Inspection Certification <br />On June 14, 2016, 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 62°F and Partially 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 83.7 feet from the ground surface, an reduction in water elevation of 0.5 feet <br />from the previous quarterly inspection. <br />reviewed the monument survey data collected on June 13, 2016. This data was compared to the <br />survey data collected during the previous quarter on December 10, 2015. After review of the June <br />13, 2016 data, the largest indicated vertical displacement from the previous quarter survey was <br />0.03 feet at the 7150 West Prism. The remaining prisms measured a displacement of 0.0 feet to - <br />0.029 ft. <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 />