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EXHIBIT D MINING PLAN <br /> 1. General Mining Plan <br /> The permit and property boundary will be surveyed prior to any site disturbance. Map C-2 shows <br /> the mining plan. <br /> The gravel zone is approximately 30 feet thick in an alluvial deposit and is overlain by soil and <br /> overburden ranging from 4 to 6 feet. The underlying geological layer is the Mancos Shale which <br /> underlies all alluvium in this valley. Therefore, no excavation will come within two feet of the <br /> shale. If any shale is exposed, it will be buried under two feet of backfill, and that depth will be <br /> the new pit floor. In general,the area will be mined by first excavating soil/overburden with front <br /> end loaders which will take that material to be used to backfill the slopes of mined out areas to a <br /> 3H:1 V slope as shown on Map F-1. The raw gravel material will then be loaded into a <br /> crusher/screen plant where various sizes of product will be made and placed in separate stockpiles. <br /> Dozers may also be used to move topsoil/overburden or gravel. Mining activities are expected to <br /> occur approximately 3 to 5 months per year, while the processing operations including <br /> screening/crushing and washing can occur any time of the year. Mining will proceed from Area 1 <br /> to Area 5 in the West Pit to Area 6 to Area 10 in the East Pit, as shown on Map C-2. The mining <br /> of the deposit will occur to the limits shown on Map C-2 and will be mined to a slope no steeper <br /> than 2H:1 V in order to maximize gravel recovery. Backfilling with overburden will create the <br /> shallower reclaimed slopes. <br /> J Graff Enterprises, LLC mines using a 0.5H:1V to near vertical slope on the active mining face. <br /> Highwall mining will progress to an offset line from the crest line, which marks the mid-slope of <br /> the 2H:1 V mining slope. Both boundaries will be staked prior to mining in the area. This offset <br /> serves two purposes. First, the volume of material left in the highwall will allow the crest to be <br /> pushed towards the toe with the final mining slope of 2H:1 V,which will maximize gravel recovery <br /> and additionally will reduce the required backfill material to bring the slopes to 3H:IV. Secondly, <br /> this offset provides additional slope safety. A failure would be governed by the internal angle of <br /> friction of the material. This would limit the failed slope to an angle of 38 degrees or—1.3H:IV. <br /> This failure would not only stay within the permit area, it would stay within the final slope <br /> envelope. Such a failure is unlikely given that only the active slope is near vertical. <br /> BRS&G Pit I X 1.1-;t .". „a 111-1--ri i t <br /> March 2019 D-2 <br />