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1 <br />Cripple Creek & Victor Gold Mining Company ■� <br />2015 Annual Arequa Gulch Valley Leach Facility Inspection <br />AngloGold Ashanti <br />Cresson Project, Victor, Teller County, Colorado <br />NewFields Project 475.0160.001 <br />December 15, 2015 <br />slope faces) and stable. The foundation and embankment slopes did not show any signs of <br />distress. <br />2.2. Pad Growth and Pad Geometry <br />Utilizing the Flyover Topography for the 2014 and 2015, NewFields developed AutoCAD Civil3d <br />surfaces for both years. NewFields compared the side -slopes and pad development looking for <br />differences between the two surfaces. The most significant change was the addition of the lift <br />within the Phases 4 and 5 limits. The ultimate height increased by approximately 100', bring <br />the maximum elevation of the AG -VLF to 10395' above sea level. Generally, all the side slopes <br />remained unchanged from the previous year and the access road on the side of the VLF show <br />signs of road maintenance performed by CC&V. <br />NewFields analyzed the side slopes of the 2015 flyover AG -VLF surface, and found the ore <br />slopes between the benches ranged between 1.3H: 1V, the designed angle of repose for the <br />ore, and 2:1 around the perimeter of the VLF. The composite slope of the VLF, measured from <br />the base of the facility to the top crest, varied between 1.8H: 1V to 2.1H: 1V. These slopes are <br />flatter than the recommended design slopes of 1.6H: IV and 2.OH: 1V as described in the letter <br />from Dr. John Lupo with AMEC Earth and Environmental, dated February 5, 2010; regarding <br />Phase 5 PSSA Ore Slopes. In the letter, Dr. Lupo amends the design slopes to those cited above <br />based on a flatter Phase 5 PSSA pond bottom than was originally envisaged in the design <br />submittal. <br />Additionally, to show the development of the AG -VLF over the previous 5 years, NewFields <br />created Figure 3. This figure shows that the pad continues to be stable and shows no signs of <br />movement. <br />3. AG -VLF UNDERDRAIN RECORDS <br />CC&V provided NewFields with flow and water quality records for the AG -VLF underdrains, and <br />reviewed as part of the annual inspection program. The purpose of the underdrain data review <br />is to identity any trends in the data that may be indicative of potential leakage from the AG -VLF <br />containment system. For this inspection program, the review focused on the underdrain flow <br />rates measured WAD cyanide concentrations, as these parameters would be directly impacted <br />if leakage from the AG -VLF should occur. <br />The data records reviewed include time histories from January 2015 through November 2015 if <br />flow and quality for the following underdrains: <br />➢ 24 inch solid pipe <br />Page 3 <br />