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approved landfill for disposal such as Front Range Landfill (approximately 40 miles to the east).Trash, <br /> weeds and other debris that will interfere with seeding operations will be removed and disposed of in <br /> an approved landfill such as Front Range Landfill (approximately 40 miles to the east). <br /> Facilities and structures that are left as part of the post mining land use will meet Boulder County <br /> building and zoning codes. <br /> 1 .2 Shafts and Portals <br /> There are currently 2 ventilation shafts,three shafts, and two portals that will require closure as listed in <br /> Table 1. <br /> Table 1 Shafts and Portals <br /> Name Size(feet) <br /> Potosi Shaft 6 x 6 <br /> Cross Shaft 8x8 <br /> Caribou Shaft 8x8 <br /> Caribou Level 300 Portal 8x8 <br /> Idaho Tunnel Portal 8x8 <br /> All shafts, adits, portals, and ventilation shafts will be closed according to the Colorado Inactive Mine <br /> Program standards and specifications(DRMS 2009). Figure 1 is an example of DRMS adit closure (DRMS <br /> 2009). We do not anticipate mine drainage or the necessity of a hydraulic plug to prevent mine <br /> drainage. Shafts and portals will be plugged with concrete except for the Potosi Shaft, which will be <br /> closed with a bat gate (Figure 2). We anticipate that a 40 ft concrete plug will seal the shafts and <br /> portals. Shafts and portals will be gated to prevent access. Fences will be 3 feet from the concreted <br /> opening and will be 8 feet high with barbed wire. Ventilation and escape way shafts will also utilize <br /> either one of the following approved standard methods shown on Figure 3 (DRMS 2009). <br /> The Potosi Shaft will be reclaimed using hand entry and hand tools. A collar and bat gates will be <br /> installed.A fence will enclose the shaft area. An example of DRMS bat gates is shown on Figure2 (DRMS <br /> 2009). <br /> All drill and auger holes will be plugged with non-combustible material and sealed with grout or neat <br /> cement according to DRMS approved methods. <br /> Slopes will be reconfigured to Approximate Original Contour(AOC)or less and will blend in with the <br /> surrounding topography. In addition, areas adjacent to mine shafts and portals will be stable but may be <br /> steeper than 2:1. Areas steeper than 2:1 will be kept to a minimum. <br /> 2 <br />