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West Pit Fill Inspection Certification <br />On December 10th, 2013, 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 below the 7,400 dump elevation, <br />inspect the revegetation on the fill surface, inspect the fill for areas of water seepage or surface <br />drainage, inspect the final grade slopes below the 7,300 elevation of the Excess Fill Slope, 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 16 °F and partly cloudy, with 5 -10 mile per hour wind. There <br />was between 5 -12 inches of snow at the time of inspection, with drifted snow in places. <br />Based upon my observations, the visible portion of the regraded fill was observed to be stable and <br />unchanged. The underdrain below the West Pit Fill was not flowing at the time of inspection. No <br />seeps in the fill or signs of erosion were noted. <br />The West Pit Fill area is complete to PMT design. The West Pit fill was topsoiled and seeded during <br />this quarter, with three contour furrows placed on the west bank of the active reclamation, and two <br />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 84.4' from the ground surface, a decrease of 0.2 feet from the September <br />inspection. <br />I reviewed the monument survey data collected on December 19th, 2013. This data was compared <br />to the survey data collected during the prior quarter on September 20th, 2013, as well as the data <br />collected on October 3rd, 2012. During the last quarter, the September 20th 2013 data showed a <br />change in elevation of 0.202 feet from the previous survey taken on June 19th, 2013 for the 7250 <br />West monitor. I stated in the last quarterly report that in my opinion, the changing of survey <br />personnel and used equipment caused the June 19th 2013 survey of the 7250 West monument to <br />be in error. The December 19th, 2013 survey confirms this opinion, as the survey taken from this <br />quarter deviates by 0.039 feet from the September 20th 2013 survey data and 0.039 feet from <br />October 3rd, 2012 survey data. <br />After review of the December 19th, 2013 data, the largest displacement from previous survey was <br />0.053 feet at the 7050 West monument, with the remaining monument data deviating less than <br />0.040 feet. The 7150 Mid monument had a displacement of 0.056 feet however the prism was <br />replaced during this quarter, likely contributing to the higher deviation. Based on this data, the total <br />displacement of the monuments are not of concern with regard to the stability of the dump. This <br />degree of deviation can be caused by survey variation, as well monument disturbance from animal <br />traffic, weather etc. During inspection, I observed no evidence of structural weakness, slumps, <br />seeps or other hazardous conditions associated with this dump. The monument survey data is <br />available for review upon request at the Colowyo Mine site. <br />