Laserfiche WebLink
West Pit Fill Inspection Certification <br />On September 19, 2016, 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:1V 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 620F 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 82.8 feet from the ground surface, an increase in water elevation of 0.9 feet <br />from the previous quarterly inspection. <br />I reviewed the monument survey data collected on September 20, 2016. This data was compared <br />to the survey data collected during the previous quarter on June 13, 2016. After review of the <br />September 20, 2016 data, the largest indicated vertical displacement from the previous quarter <br />survey was -0.08 feet at the 7150 West Prism. The remaining prisms measured a displacement of <br />0.0 feet to -0.052 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 />owPp 0 l: CF <br />�s <br />-,<T 47031 <br />�o .• 1-21-/b <br />i •. .• <br />��j F� 090000•60 �� �� <br />