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original contour(AOC) in the SL-21 area, elevation data provided in the SL-21 partial bond <br /> release application was compared to GPS data collected by the Division. A total of eight GPS <br /> points were taken, three along the Reclamation Parcel WP033 and five along Reclamation Parcel <br /> WP034. GPS points were placed at selected transects between approximately 100 - 200 feet <br /> intervals and along contour elevations in ArcGIS and those points were then downloaded on <br /> ArcGIS for ESRI Collector(Collector). Locations of these points are shown on Figure 2 of this <br /> document. During the bond release inspection, the Division navigated to the points using the <br /> data in Collector and a GPS data point was collected at each predetermined location along the <br /> transect. Each reclamation parcel was also visually inspected to ensure the area was graded and <br /> blended in with the adjacent reclaimed areas. During the inspection, no signs of erosion or issues <br /> were encountered. <br /> For comparison reasons, a known point was collected at the Colowyo Mine office to determine a <br /> correction factor for the elevation of the bond release areas collected with the GPS. In <br /> Colowyo's coordinate system (UTM NAD 27 Colorado State Plane)the elevation is 7,261' at the <br /> known base station and was measured by the Division at an elevation of 7,284'. The difference <br /> between the elevations was 23 feet which will be used as the correction factor. <br /> The elevation data collected for the West Pit by the Division was compared to elevation <br /> information provided in the SL-21 Bond Release application and shown on Table 4 of this <br /> document. After comparison, all elevation points taken by the Division were found to have an <br /> average difference of approximately 5 feet from the approved elevations shown on SL-21 Map 1. <br /> Given the expanse of the mine site and the steepness of the terrain at Colowyo,the Division <br /> determined that the difference in elevation is acceptable. <br /> Summary and Conclusions <br /> The Division has completed its review and evaluation of the SL-21 partial Phase I Bond Release <br /> application submitted by Colowyo for the Colowyo Mine. The Division proposes to approve this <br /> Partial Phase I Bond Release on 13.3 acres for portion of the West Pit. Based upon a review of the <br /> mine permit,the applicant's bond release application, and site inspections,the Division finds that <br /> Colowyo has completed drainage reestablishment with the approved post-mining topography that <br /> resembles the general surface configuration of the land prior to mining, and supports the <br /> approved post-mining land use. The reclamation parcels required under SL-21 conforms to post- <br /> mining contours as shown on the approved Postmining Topography Map of the PAP (Map 19 <br /> and 19B) and was stable at the time of the inspection. The Division finds that Colowyo has <br /> achieved the requirements for partial Phase I Bond Release at the Colowyo Mine. <br /> V. PROPOSED DECISION <br /> Based on the observations in Section IV above,the Colorado Division of Reclamation,Mining, and <br /> Safety proposes to approve Colowyo's request for a partial Phase I Bond Release for the Colowyo <br /> Mine. This proposed decision will release the applicant of Phase I reclamation liability on 13.3 <br /> acres for portion of the West Pit, as shown on Figure I at the end of this document. <br /> Proposed Decision and Findings of Compliance June 24,2022 <br /> Partial Phase I Bond Release SL-21 Page 6 <br />