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West Pit Fill Inspection Certification <br />On November 25th, 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 />3HIV 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 4.09.1(1)(c) and Rule 4.09.1(11). At the time <br />of inspection, weather conditions were 25 °F and windy, with snow on the ground. <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' from the ground surface, an increase in water elevation of 0.7 feet from <br />the previous quarterly inspection. <br />I reviewed the monument survey data collected on December 16th, 2014. This data was compared <br />to the survey data collected during the previous quarter on September 15th, 2014. After review of <br />the December 16th, 2014 data, the largest displacement from the previous quarter survey was 0.017 <br />feet at the 7150 West monument. <br />Last quarter, the 7250 West monument prism was missing, and was replaced during this quarter. <br />During survey, it was discovered that the prism used as the replacement 7250 West Monument <br />prism was non - functional, and no measurement could be taken. Colowyo will find a suitable <br />replacement prior to the first quarter 2015 inspection. No slumps, seeps or other signs of movement <br />were observed around the 7250 west prism during inspection. <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 measured displacement can be caused by normal settlement, <br />survey variation, and monument disturbance from animal traffic, weather etc. During inspection, I <br />observed no evidence of structural weakness, slumps, seeps or other hazardous conditions <br />associated with this fill. The monument survey data is available for review upon request at the <br />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 />P <br />47031 _ <br />