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EXHIBIT D MINING PLAN <br /> 1 . General Mining Plan <br /> The property boundary has been surveyed on site and the permit area will be surveyed prior to <br /> any site disturbance. Map C-2 shows the mining plan. <br /> The gravel zone is estimated to be 40-70 feet thick in an alluvial deposit and is overlain by 1-3 <br /> feet of topsoil and overburden at its deepest areas. The mineable Quaternary-late Pleistocene <br /> Uncompahgre alluvial deposit overlies the Mancos Shale with a contact depth of between 40-70 <br /> feet below the surface. Because the contact surface of the overlying gravel to the Mancos <br /> Shale is unconformable, exact locations of the boundary are difficult to determine prior to mining <br /> and without analysis of drill logs. Very limited outcrops of the Mancos Shale may be observable <br /> at the northern drainage cut that exits the northeast corner of the site. Therefore, while mining is <br /> planned to a total depth of 70 feet, the operator will not mine into any shale encountered. In the <br /> event that mining, prior to 70 feet of depth, reaches a shale zone, the pit will be backfilled to two <br /> feet above the shale zone and this elevation will become the new maximum pit depth. <br /> In general, the site will be mined by first excavating soil/overburden with front end loaders which <br /> will be stockpiled on site. This material will be used later to backfill the slopes of mined out <br /> areas to a 3H:1 V slope during reclamation as shown on Map F-1. The raw gravel material will <br /> then be loaded into a crusher/screen plant where various sizes of product will be made and <br /> placed in separate stockpiles. Dozers may also be used to move topsoil/overburden or gravel. <br /> The direction of mining will be from the north to the south. Mining activities are expected to <br /> occur approximately 4 to 6 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 8 as shown on Map C-2. The mining of the deposit will occur to the limits shown on Map C-2 <br /> and will be mined to a slope no steeper than 2H:1 V in order to maximize gravel recovery. <br /> Backfilling with overburden will create shallower reclaimed slopes. <br /> BDF, LLC mines using a 1 H:1 V to near vertical slope on active mining faces. Highwall mining <br /> will progress to an offset line from the crest line, which marks the mid-slope of the 2H:1 V mining <br /> slope. Both boundaries will be staked prior to mining in the area. This offset serves two <br /> purposes. First, the volume of material left in the highwall will allow the crest to be pushed <br /> towards the toe with the final mining slope of 2H:1 V, which will maximize gravel recovery and <br /> additionally will reduce the required backfill material to bring the slopes to a 3H:1V slope. <br /> Secondly, this offset provides additional slope safety. A failure would be governed by the <br /> internal angle of friction of the material. This would limit the failed slope to an angle of 34 <br /> degrees or-1.3H:1V. This failure would not only stay within the permit area, it would stay within <br /> the final slope envelope. Such a failure is unlikely given that only the active mining slope is near <br /> vertical. <br /> Base Products Gravel Pit 2 D-1 Lewicki&Associates <br /> April 2022 <br />