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provided in the SL -13 Bond Release application was compared to GPS data collected by the <br />Division. A total of 22 points were taken along the West Pit (WP024), East Pit (EP060) and <br />Administration Building area (GFO1). Two transects with a total of 16 points were taken along <br />the West Pit and two additional points taken at the north end of the West Pit. Four points were <br />also collected along the East Pit and Administration Building areas (see Figures 3 and 5). Points <br />were placed at selected transects at approximately 200 feet intervals and along contour elevations <br />in ArcGIS and those points were then downloaded on ArcGIS for ESRI Collector (Collector). <br />During the bond release inspection, Zach Trujillo navigated to the points using the data in <br />Collector and a GPS data point was collected at each site with a Bad Elf GNSS (Bad Elf) <br />surveying unit. The Division then inspected reclaimed parcels ST005, WP022, CO1, CO2, C05, <br />and WR -1 through WR -4 (see Figures 1 and 2). Due to the smaller size of each parcel, no GPS <br />points were taken and instead were visually inspected for compliance. Each reclamation parcel <br />visually inspected was graded, and blended in with the native undisturbed adjacent land. <br />Geotechnical drill holes WR -1 through WR -4 could not be located due the nature of being <br />sealed, backfilled and new construction over the area. No issues were observed at the visually <br />inspected reclamation parcels. <br />The static accuracy of the Bad Elf is approximately 1 meter with SBAS+PPP and is on a <br />localized geoid. For comparison reasons, a known point was collected at the Colowyo Mine <br />office to determine a correction factor for the elevation of the bond release areas collected with <br />the Bad Elf. In Colowyo's coordinate system (UTM NAD 27 Colorado State Plane) the <br />elevation is 7,262.91' at the known base station and was measured by the Division at an <br />elevation of 7,274.57' with the Bad Elf. The difference between the elevations was 11.66 feet <br />which will be used as the correction factor. <br />The elevation data collected by the Division was compared to elevation information provided in <br />the SL -13 Bond Release application. After comparison, all elevation points taken by the <br />Division were found to have an average of deviation of 16 feet from the elevations shown on SL - <br />13 Map 3. Given the expanse of the mine site and the steepness of the terrain at Colowyo, as <br />well as the error contributed by the user, the Division determined that the difference in elevation <br />is acceptable. <br />For the West Pit, East Pit, Old Administration Building area, and the Collom ancillary expansion <br />areas, the Division finds that the Colowyo Mine has achieved a post -mining surface that <br />conforms to the approved post -mining topography and resembles the general surface <br />configuration of the land prior to mining. All highwalls have been eliminated and the reclaimed <br />lands blend in well with the adjacent undisturbed slopes. No settling, slumping or cracking of <br />the backfill were noted in the partial Phase I Bond Release area. While no channels or ditches <br />are included in SL -13, the post -mining channels that run through the reclamation parcels were <br />stable and well armored with no visible signs erosion or cutting. <br />Summary and Conclusions <br />The Division has completed its review and evaluation of the SL -13 partial Phase I Bond Release <br />Proposed Decision and Findings of Compliance August 30, 2018 <br />Partial Phase I Bond Release SL -13 Page 6 <br />