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The lands owned by ERMR-Lloyd, ERMR-Benson West and Morgan will all be returned to <br />approximate contour, with a similar drainage pattern to the pre -mine conditions. In areas of <br />minor topographic change, the land has been improved by having a more consistent slope over <br />broad areas, which will facilitate irrigation of fields. The ERMR-Johnson parcel has a modified <br />topography with the following properties (determined using Carlson CAD software): <br />Table 2.05.4(2)(c)-1: WFC Property Topography Properties <br />The new surface drainage patterns for the ERMR property are shown on Map 2.05.3(3)-l-2. The <br />backfilling sequence for west of 27.00 Road is shown on both Map 2.05.3(4)-1-2 and <br />Attachment 2.05.4(2)(c)-7. The mining cuts from Attachment 2.05.4(2)(c)-7 correlate to the <br />numbered cuts on Map 2.05.3(4)-1-2. <br />The backfilling sequence has been designed to minimize the need for stockpiling of overburden <br />and material re -handling. For most of the mine sequence this is done with cast blasting of the <br />initial overburden into the previously mined out open cut. The remaining overburden material is <br />then hauled from the new mining cut into the mined out cut. In most cases this leads to each cut <br />backfilling the one that precedes it (ex: Cut -92 material backfills Cut -91). However, as the shape <br />of the mining area changes (Cut -94 and Cut -95), not enough material is generated from new <br />excavation to backfill the previous cut. <br />In order to mitigate this problem and ensure that post -mine topography is achieved, two things <br />are done. Firstly, the mining cut that needs more backfill than the next cut can generate will <br />remain "open" until enough material is generated by mining to successfully backfill. Secondly, <br />backfill will be hauled from a variety of cuts ahead of the "open" cut and used to fill the "open" <br />cut. The source cuts for backfill material can be seen in the Backfill Source column of <br />Attachment 2.05.4(2)(c)-7. <br />At the west end of the Morgan property, the Bench 1 material from Cut -99B will be stockpiled in <br />non-topsoiled areas of the Morgan property to the east of the mining. This is to ensure that all <br />Bench 1 material excavated from the Morgan property is also backfilled onto the Morgan <br />property. Since the mining cuts on the west end of the Morgan property are the end of mining on <br />the Morgan property, the Bench 1 material from Cut -99B will have to be split between Cut -99B <br />and Cut -98B. This can be seen on Attachment 2.05.4(2)(c)-7. <br />Page 2.05.4(2)(c)-3 July 2018 (TR -84) <br />Pre -Mine Topography <br />Post -Mine Topography <br />Average Elevation <br />5,624' <br />5,610' <br />Maximum Elevation <br />5,673' <br />5,660' <br />Minimum Elevation <br />5,550' <br />5,560' <br />Average Land Slope <br />2.7% <br />4.0% <br />Steepest Slope <br />37.7% <br />38.5% <br />The new surface drainage patterns for the ERMR property are shown on Map 2.05.3(3)-l-2. The <br />backfilling sequence for west of 27.00 Road is shown on both Map 2.05.3(4)-1-2 and <br />Attachment 2.05.4(2)(c)-7. The mining cuts from Attachment 2.05.4(2)(c)-7 correlate to the <br />numbered cuts on Map 2.05.3(4)-1-2. <br />The backfilling sequence has been designed to minimize the need for stockpiling of overburden <br />and material re -handling. For most of the mine sequence this is done with cast blasting of the <br />initial overburden into the previously mined out open cut. The remaining overburden material is <br />then hauled from the new mining cut into the mined out cut. In most cases this leads to each cut <br />backfilling the one that precedes it (ex: Cut -92 material backfills Cut -91). However, as the shape <br />of the mining area changes (Cut -94 and Cut -95), not enough material is generated from new <br />excavation to backfill the previous cut. <br />In order to mitigate this problem and ensure that post -mine topography is achieved, two things <br />are done. Firstly, the mining cut that needs more backfill than the next cut can generate will <br />remain "open" until enough material is generated by mining to successfully backfill. Secondly, <br />backfill will be hauled from a variety of cuts ahead of the "open" cut and used to fill the "open" <br />cut. The source cuts for backfill material can be seen in the Backfill Source column of <br />Attachment 2.05.4(2)(c)-7. <br />At the west end of the Morgan property, the Bench 1 material from Cut -99B will be stockpiled in <br />non-topsoiled areas of the Morgan property to the east of the mining. This is to ensure that all <br />Bench 1 material excavated from the Morgan property is also backfilled onto the Morgan <br />property. Since the mining cuts on the west end of the Morgan property are the end of mining on <br />the Morgan property, the Bench 1 material from Cut -99B will have to be split between Cut -99B <br />and Cut -98B. This can be seen on Attachment 2.05.4(2)(c)-7. <br />Page 2.05.4(2)(c)-3 July 2018 (TR -84) <br />