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Well AVF3 with a known elevation of 6137.95 feet is located in parcel 11. The elevation measured in the <br />field was 6153.7 feet a difference of 16.7ft. Many variables affect the precision of field -collected <br />elevations measured with a handheld GPS unit. This difference was generally but not always consistent <br />when the field measurements were compared with the Reclamation Plan Map (Map 29) as illustrated <br />below in the graphed transect. Numerous measurements however corresponded very well with the <br />reclamation plan map. However, as demonstrated by the data collected and illustrated below, the <br />difference in field collected elevation appears generally consistent throughout the site and corroborates <br />MCMs approved post mining topography. <br />Using a Bad Elf GPS tool and ARCCollector in <br />the field, DRMS took elevation points throughout <br />the requested bond release block. Using <br />Microsoft Excel® (Table V), the Division charted <br />the PMT from Map 29; Reclamation Plan <br />Map of 1996, and the on the ground measured <br />elevations comparing elevation values from the <br />two sources. The illustrations below show transect <br />locations, and field collected points in relationship <br />to the Reclamation Plan Map exhibiting the <br />elevation differences between the MCM map and <br />field collected information. <br />Because of the age of the 1996 reclamation map and <br />the quality of the topography illustrated DRMS <br />found it difficult to precisely compare field <br />collected data. DRMS georeferenced numerous <br />other permit maps including Map 11, the <br />Hydrologic Monitoring map, the Annual <br />Reclamation Plan Map and Map 29 the 2020 <br />Reclamation Plan Map submitted as part of TR38 <br />in order to better ascertain the elevation as per the <br />permit mapping. However, these maps possessed <br />The mine water ditch in parcel 26looking west. other problems such as features obscuring elevation <br />callouts and topographic lines or, a paucity of topographic lines. <br />When considering Map I above, showing the location of field collected elevation data, it appears that <br />some points fall outside the reclamation parcel. Both DRMS and the operator discussed the data, and data <br />collection methods. DRMS and MCM are confident that the data collected was collected inside the <br />parcel. The following accuracy and precision issues appear to be at work: <br />o The horizontal and vertical error inherent in GPS data collection <br />o The number of satellites fixed on a point at the time of collection <br />o Differences in map projections and the number of projection transformations necessary <br />As demonstrated by the map review, the data collected and illustrated below, MCM's approved post <br />mining topography corresponds to what exists today at the site. The Division finds that MCM has met <br />Permit Number. C1981044 Page 10 of 14 <br />