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<br /> <br /> <br /> <br /> <br />Permit Number C1981028 Prepared by: R. Reilley, MS, GISP <br />SL9 7 <br /> <br />Energy Company and Robin Reilley with the Division of Reclamation Mining and Safety. The weather <br />was clear. <br /> <br />Compliance with Approved Post Mining Topography <br /> <br />The Division evaluated the reclamation parcels to determine if the affected areas have been backfilled <br />and graded in accordance with the approved post mine topography (map entitled Post Mining <br />Topography), available in Appendix 2 of the permit document. During the Phase I field inspection, the <br />Division collected data for use in validating the on the ground topography of the bond release parcels. <br />To evaluate the SL9 bond release block for Phase 1 bond release, the Division compared the approved <br />post mining topography (PMT) as depicted on the Post Mining Topography Map with the Vegetation <br />and Revegetation Map submitted with the SL9 application to the actual on the ground conditions after <br />backfilling and grading as per field collected data points. The charts and associated data table comprise <br />DRMS’s analysis and are presented in the Findings section of this document. <br /> <br />Using the ArcMap 10.3.1 application for mapping and analysis, the Division geo-referenced the above <br />referenced maps and walked four transects through the reclamation parcels to be evaluated, overlaying <br />the transect dataset on the map thus allowing for a visual comparison of the topography and field <br />collected data. <br /> <br /> <br />Photo 2: Collecting a known elevation with <br />the Bad Elf GNNS Survey instrument. (Stock <br />photo.) <br /> <br />A surveyed elevation point, maintained by CEC and <br />known to be 4813.92 feet above sea level and is located <br />outside the permit boundary near the fence line of the <br />composting plant. The Division measured the elevation with <br />a Bad Elf GNSS (Global Navigation Satellite System) <br />surveyor. <br /> <br />During the ground inspection, the Division walked each <br />transect, logging elevation points using the Bad Elf. The GPS <br />device uses height above the reference ellipsoid that <br />approximates the earth’s surface, (GNNS Alt or ellipsoidal <br />height) and is measured in meters. This value requires <br />conversion to elevation above mean sea level. The associated <br />calculations are explained as follows and data are available in Table 1. The GNSS altitude as measured <br />by the Bad Elf was converted to feet (measured elevation). In order to obtain height above mean sea level <br />for each point, an orthometric height had to be calculated. The orthometric height approximates mean <br />sea level and is the difference between GPS ellipsoid height and geoid height. This was accomplished in <br />a two step process using the UNAVCO calculator found here: <br />https://www.unavco.org/software/geodetic-utilities/geoid-height-calculator/geoid-height-calculator.html <br />Entering the Latitude, Longitude and GPS elevation, the conversion is made by submitting this <br />information. For an explanation of the geodesy associated with these terms, please see: <br />http://www.esri.com/news/arcuser/0703/geoid1of3.html