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Incomplete Reclamation <br />In the West Pit, the reclamation in some areas could not be checked due to the presence of <br />topsoil stockpiles, a rock stockpile (riprap staged for drainage construction), and a scraper road. <br />The topsoil and the riprap are shown on Figure 1. The scraper road was not surveyed by the <br />Division but ran along the eastern side of the western parcel in Figure 1. <br />The Division suggested that Colowyo Coal Company follow one of two courses of action: <br />1. Postpone approval of the SL -07 application until these features are removed from the <br />reclaimed areas (i.e., spread the topsoil, use the riprap in drainage construction, and <br />reclaim the scraper road). <br />2. "Carve out" the areas in question from the SL -07 application. <br />Colowyo chose the latter course of action and re- submitted portions of the application including <br />Exhibit 1, the map of the bond release areas. The updated map is Figure 4 below. The new <br />amount of total acreage in the application is 125.2 acres. <br />Backfilling and Grading <br />For the SL -07 areas that did not contain topsoil stockpiles, rock stockpiles, or scraper roads, <br />observations were made during the bond release inspection with regard to approximate original <br />contour and stability of the reclaimed landscape. <br />To determine compliance with Colowyo's approved approximate original contour (AOC) in the <br />SL -07 areas, elevation data provided in the SL -07 Bond Release application was compared to <br />GPS data collected by DRMS staff. Twenty -five points were selected near the cross - sections of <br />the reclamation areas and 10 locations were selected along the Final East Pit Ditch and the West <br />Taylor Fill side ditches. These points were selected by utilizing Exhibit 1 of the SL -07 <br />application. Points were placed at selected contour elevations in ArcGIS (to try to cover the <br />majority of the area), and those points were then downloaded into a Trimble Yuma. During the <br />bond release inspection, Jason Musick navigated to the points using the data in the Trimble, and <br />a GPS data point was collected at each site. The points collected at the site were downloaded <br />from the Trimble into Pathfinder office and converted into a point shape file to utilize in ArcGIS. <br />Elevation data using the Trimble Yuma is not exact. The Geoid used in the Trimble GeoXT is <br />DMA 10X10 Global, which is a global elevation Geoid and not as accurate as a localized Geoid. <br />For this reason a known point was collected at the Colowyo Mine office to determine a <br />correction factor for the elevation collected in the Trimble Yuma. The elevation at the base <br />station was 7287.6' on the Trimble Yuma, which utilizes a projected coordinate system of UTM, <br />NAD 83, Zone 13 North. In Colowyo's coordinate system (UTM NAD 27 Colorado State <br />Plane) the elevation is 7263.1. Thus, a correction of approximately +24.5 feet is necessary to <br />make comparisons of elevation data. The elevation data was corrected and post - processed. <br />Proposed Decision and Findings of Compliance August 2013 <br />Partial Phase I Bond Release SL -07 Page 6 <br />