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Post Mining Topography Strip Pit <br /> Strip Pit <br /> 6309 <br /> 6306 <br /> LL <br /> 0 <br /> 6274 <br /> 6288 <br /> +� 6231 <br /> v <br /> "' 6212 <br /> 1 2 3 <br /> f Elev Measured(Ft) f Elev Map(Ft) <br /> Graph 3: Strip Pit Transect <br /> The Division confirms that reclamation parcels have been backfilled and graded in accordance with the <br /> approved post-mining topography and that drainage control has been accomplished. <br /> Phase H <br /> MCM analyzed the topsoil depths in both the Strip Pit and the Utah Tract in the autumn of 2018 to <br /> verify that topsoil replacement had occurred as per the reclamation plans for each parcel. The analysis <br /> can be referenced in Attachment E of the Bond Release Application. For the Utah Tract,27 topsoil depth <br /> measurements were recorded and found to range between 13 and 17 inches averaging 15 inches; exceeding <br /> 12 inch reclamation plan requirements. For the Strip Pit, 15 measurements were recorded ranging from 10 <br /> to 17 inches and averaging 13.4 inches. <br /> Sedimentology <br /> The condition of the sediment ponds and any needed maintenance on the ponds receiving runoff from the <br /> bond release parcels were evaluated. Ponds receiving runoff from the bond release parcels are not <br /> receiving flow from affected lands not under consideration for bond release at this time. MCM's bond <br /> release utilized the RUSLE equation to predict and compare the gross annual erosion per acre on the <br /> reclaimed and vegetated parcels and compare them to the undisturbed reference areas. The RUSLE is an <br /> empirical formula approximating expected sediment yield from a parcel of land. It is reasonable to <br /> hypothesize that the RUSLE is useful for discriminating between two significantly different yield rates. <br /> For the bond release parcels in SL4,MCM calculated a sediment yield rate in the reference areas and a <br /> postmining rate in the bond release parcels as per tables G1 and G2 below. The difference between these <br /> two calculated rates illustrates that the postmining rate of sediment yield is less than the yield in the <br /> reference areas. This conclusion is only valid if reasonable variables are employed in the RUSLE <br /> Permit Number C1981044 Page 16 of 25 <br />