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Other Areas <br />1. All maps have been revised to more accurately reflect on-site conditions. <br />2. Direction of mining and mining limits both 3H:1 V and O.SH:I V have been added to the <br />maps. <br />3. Material to fill the buffer is located in a overburden stockpile shown in maps C-1 and C- <br />2. Remaining highwall slopes will be filled by dozing the crest of the slope towazds the <br />toe to achieve the 3H:1 V final slope. If more fill is needed the visual berm along the <br />southern edge of the permit will be used. Sufficient topsoil exist in the two stockpiles <br />seen in Map C-1 and C-2. <br />4. Mazkers will be placed on site to denote the permit boundary, the limit of the 3H:1 V crest <br />and the limit of the O.SH:1 V mining. <br />5. This issue is being addressed in two ways. All existing slopes will be filled as agreed at <br />the on-site meeting. All future steep slopes(O.SH:1 V) will be limited to a 65 foot offset <br />from the permit boundary. This offset is derived from a 20 foot offset for the crest of the <br />3H:1 V slope plus a 45 foot offset. The 45 foot offset serves two purposes. First, the <br />volume of material left in the highwall will allow the crest to be pushed towazds the toe <br />with final slope of 3H:1 V requiring no backfill material. Secondly, this offset provides <br />additional slope safety. It should be noted that the current highwalls with O.SH:1 V slopes <br />demonstrate a greater than l safety factor. It is demonstrated through no evidence of <br />slope failure during the life of the pit. However, 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 <br />38 degrees or ~1.3H:1 V. This failure would not only stay within the permit area, it would <br />stay within the final slope envelope. <br />6. Three zones along the river bank have been determined to require erosion protection. <br />These locations can be seen on Maps C-2 and F. Some previous work has been done on <br />the banks using concrete slabs and rip-rap. This work will be augmented through the <br />application of 4' d50 boulders and/or precast erosion control concrete blocks. These <br />blocks were designed for the highly erosive Animus River. The block dimensions are <br />4'x3'x3' and aze designed to be interconnected with wire rope. These materials will be <br />placed starting at the toe of the low water level and cover a 14' slope length up the bank. <br />The slope will be maintained at 2H:1 V or milder in the erosion control azeas. <br />7. The site has two well permits in place. These permits account for 34 acres of exposed <br />surface azea. The well numbers aze 39428-F and 050203-F. These two permits will <br />account for the exposed water if mining is stopped and the divider is replaced. Due to <br />this stretch of the Gunnison River becoming over appropriated very recently, the <br />remaining exposure planned for this pit will be covered through an augmentation plan. <br />This plan is currently being prepazed. <br />