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straight up in a line ahead of the backfilling operations on top of the backfilled bench of ash and mine <br />waste rock. As CEC backfills a parcel with overburden, this material is placed up to or above the level <br />of the line of six foot poles. Previous DRMS inspections from 2006 through 2013 observed Areas 30, <br />31 and 32 being backfilled with overburden and were found to be in compliance. <br />In order to determine if the bond release parcels have been backfilled and graded to approximate the <br />approved post mine topography, the Division compares the post mine contours of the parcels to the <br />approved post mine topography and then field verifies the final topography. With the SL7 bond release <br />application, CEC submitted a map (Figure 2) that depicts the final topography of the site based on aerial <br />survey. The Division used this map to compare the topography to the approved post mine topography <br />depicted on the Appendix Q -1 map from the permit. The final topography was verified during two site <br />inspections, one on February 5, 2015 and the other on February 24, 2015. The overall shape and slope <br />of the reported post mine topography approximates the approved post mine topography. <br />In accordance with the "Guideline Regarding Selected Coal Mine Bond Release Issues," dated April 18, <br />1995, the Division evaluates the following items during a Phase I bond release inspection to determine <br />compliance with Rule 3.03.1(2)(a): <br />1. Hillslope and drainage channel gradient and general design compliance. <br />2. Performance of the reconstructed topography. Symptoms of failures or instabilities such as <br />slumping or exposed highwalls will be examined. <br />3. Hillslope design /function with regards to erosion. <br />4. Swales and depressions with regard to number of such features and effect on the post mine land <br />use. <br />5. Blending of regraded land to undisturbed areas. <br />6. The functioning of drainages with regard to nickpoints, blending at disturbance boundaries and <br />channel erosion. <br />7. Erosional Features. <br />8. Drainage control for the reclaimed area. <br />In order to evaluate item 91 listed above during the February 5, 2015 inspection, the Division collected <br />GPS data to verify the final topography. Using a YUMA GPS unit, the Division collected points along <br />transects that bisected the bond release parcels and a transect down the western drainage. At each <br />collection point, the elevation was recorded with the GPS unit. For each collection point, the elevations <br />are then interpolated from both the Appendix Q -1 map to ascertain the approved post mine elevation and <br />the SL7 Figure 2 map to ascertain the reported post mine elevation. Using this data, the Division can <br />evaluate the average difference in elevation between the reported post mine topography, the measured <br />post mine topography and the approved post mine topography. Also using this data, the Division can <br />generate cross sections of the approved post mine topography, the reported post mine topography and <br />the measured post mine topography for each of the transects bisecting each of the bond release parcels <br />and the reclaimed parcels. The Division encountered an error when processing the data collected during <br />the February 5, 2015 inspection. The elevations collected during the inspection did not appear to be <br />accurate or correlate with either the approved post mine topography, the reported post mine topography <br />or the Division's visual observations of the reclamation parcels. The data collected on February 5, 2015 <br />did not represent the actual post mine topography. Given this, the Division conducted an additional <br />Page 5 of 8 <br />