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Cross Gold Mine <br />December 2024 E-5 <br /> <br /> <br />Mine Lands Program suggested seed mix. The area will be seeded and hydromulched. Seeds will be <br />planted during fall of reclamation year one. Trees and shrubs will be hand planted during the spring of <br />reclamation year two to further reduce potential erosion and to enhance blending into surrounding <br />landscapes. (Section 1.10). The area will be evaluated weekly during reclamation year two summer <br />season to check on reseeding and planting success. Supplemental water of trees and shrubs may be <br />warranted on occasion. The stability of replaced topsoil on this graded slope will be assured by <br />roughing in final grading to reduce slippage zones. Runoff along slopes will be controlled with erosion <br />and sediment control structures to minimize rill and gully on slopes (Section 1.13). <br /> Potosi Shaft <br />If the Potosi Shaft is put into use, that construction and use would be permitted in a later Technical <br />Revision to the mine permit, and the reclamation of the construction required to use the shaft will be <br />different than that presented here. This reclamation plan assumes that the shaft has been evaluated <br />and is not used. <br />The Potosi Shaft will be closed using the precast concrete panel closure shown in Figure 2 of Exhibit D. <br />The fencing will be removed prior to closure and the materials recycled or disposed of according to the <br />reclamation plan (Exhibit D, Section 1.1). The concrete panels will be 3 by 3 feet by 1 foot, with 1 foot <br />wire and/or rebar for reinforcement, and will be secured with bolted panel footings. The Potosi Shaft <br />closure will use 9 panels (3x3 array), and two 10-foot support beams fixed with concrete as shown in <br />the detail in Figure 2 of Exhibit D. The concrete to be used for panels and beams will have a minimum <br />compressive strength of 3,000 psi. A grated access door will not be used in the concrete panels <br />because the closure will be recontoured. <br />Following construction of the concrete panel closure, the gentle hillside contour at the Potosi Shaft will <br />be restored to original contour within the disturbance zone, burying the panels. Material excavated <br />during historic shaft construction will be used. The estimated disturbance area requiring revegetation <br />and erosion control is the dimension of the disturbance area (45 by 60 feet because of fencing <br />removal.) The shaft closure will be fenced with a 5x5 foot chain link fence and will be posted for hazard <br />and trespass. <br /> Cross Ventilation Shaft and Escapeway <br />The Cross Ventilation Shaft and Escapeway will use the concrete panel closure shown in Figure 2 of <br />Appendix E-1. Any fencing will be removed prior to closure and the materials recycled or disposed of <br />according to the reclamation plan (Section 1.1). The panels will be 3 by 3 feet, with 1 foot thickness, <br />wire and/or rebar reinforced, and will be secured with bolted panel footings. The Cross Ventilation and <br />Escapeway Shaft closure will use 6 panels (2x3 array), and one 8-foot support beam fixed with <br />concrete in accordance with the detail in Figure 2 of Appendix E-1. Panel and beam concrete will have <br />a minimum compressive strength of 3,000 psi. A grated access door will not be used in the concrete <br />panels because the closure will be recontoured. <br />Following construction of the concrete panel closure, the hillside contour at the Cross Ventilation and <br />Escapeway Shaft will be restored to approximate original contour by burying the panels. Material left <br />over from historic shaft construction will be used. The estimated disturbance area requiring