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West Pit Fill Inspection Certification <br />On September 17th, 2014, 1 inspected the area in which the West Pit Excess Spoil Fill was <br />constructed. The purpose of this inspection was to observe the surface rock drain that borders the <br />3H:1 V Excess Fill Slope, inspect the areas dumped to final grade, inspect the revegetation on the <br />fill surface, inspect the fill for areas of water seepage or surface drainage, inspect the final grade <br />slopes, and satisfy the requirements of CDRMS Rule 4.09.10 (1a) and Rule 4.09.1 (1b). At the time <br />of inspection, weather conditions were 70 °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 other seeps, slumps or <br />signs of significant erosion were noted on the fill surface. The ground surface had mature <br />vegetative growth. <br />The current water level of the monitoring piezometer was obtained. The water level taken at the <br />time of inspection was 84.4' from the ground surface, a decrease in water elevation of 0.2 feet from <br />the previous quarterly inspection. <br />I reviewed the monument survey data collected on September 15th, 2014. This data was compared <br />to the survey data collected during the previous quarter on June 23rd, 2014. After review of the <br />September 15th, 2014 data, the largest displacement from the previous quarter survey was 0.047 <br />feet at the 6950 East monument. The 7250 West monument's prism was missing, so information for <br />that prism was ignored for this quarter. The prism will be replaced. <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 />i <br />47031 <br />