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During reclamation, the earthwork contractors found that a shelf of bedrock extended further <br /> south from the ridge line immediately to the east of the reclaimed Elk Creek Channel than <br /> expected. It was neither practical nor desirable to break up the bedrock, and the final topography <br /> was slightly changed from the design as a result. <br /> The East Yard was the last area to be graded which allowed it to act as a float in the event there <br /> was less material than had been estimated. As a result, the final topography was slightly changed <br /> from the design. <br /> Figure 5 shows the DTM shaded by slope angle, with slopes shallower than 50% (2H:1V) <br /> colored yellow, and steeper slopes shaded red. Of note is the steepness of the natural <br /> topography, with most of the land outside of the SL-1 parcels in the Elk Creek drainage <br /> steeper than 50%. Most of the reclaimed land inside the SL-1 parcel boundaries was graded <br /> to a slope shallower than 50%, although there are several exceptions. The exceptions are <br /> dictated by features of the natural topography, specifically: (i) the end points of the reclaimed <br /> channel are at fixed locations and determine the bottom of the slope; (ii) the bedrock shelf <br /> noted above determines the top of the slope on the east bank of the channel; and (iii)the haul <br /> road is approved as permanent, and determines the top of the slope on the west bank of the <br /> channel. <br /> The Elk Creek Mine Channel Designs table in Exhibit 2.05-E3 Section 7 of the PAP specifies <br /> slopes of 3-5% and 6-13%for the reconstructed Elk Creek channel segments through the <br /> middle and lower pads respectively, with a bottom width of IOft, side slopes of 3H:1V, and a <br /> total depth of 1.8ft. <br /> Figure 6 shows elevation/slope profiles for the two sections of the reconstructed Elk Creek <br /> stream channel that run through the SL-I parcels. Minimum elevation values were taken at <br /> 1Oft intervals from a 20ft wide corridor drawn along the approximate channel path on the <br /> DTM, and are plotted in blue against the primary vertical axis. The slope was calculated at <br /> each point based on the 20ft segment surrounding the point. A rolling average of the slope <br /> values within each 100ft segment was then calculated and is plotted in black against the <br /> secondary vertical axis. The slope for the segment through the middle pad was between -1% <br /> and -7%, with an average of-4.2%. The slope for the segment through the lower pad was <br /> between -4% and -15%, with an average of-9.4%. The DTM is not of sufficient resolution to <br /> accurately characterize the channel cross section. Field measurements taken during the SL-1 <br /> inspection showed that the channel width and depth exceeded the specified values at the <br /> points measured. The Division determined that it was not practical to measure the channel <br /> side slopes. <br /> Temporary ditches T-I and T-2 are shown on Map 2.05-M6 Sheet I of the PAP, and are <br /> intended to divert sediment from the reclaimed slopes through the existing system of culverts and <br /> ditches to Pond B until sufficient vegetative cover has been established to control erosion. <br /> The construction of T-I and T-2 was documented in inspection reports from the summer of 2018 <br /> onwards, and the location of the ditches can be inferred from the purple contour lines in Figure 4. <br /> C-1981-022,SL-1 Page 14 of 19 <br />