2021-12-29_PERMIT FILE - M2021009 (9)

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25. On page D-11, the application states the waste rock landform will be constructed by edge dumping in lifts of approximately 50 feet in height, creating an initial 1 H:1 V slope, which will then be bulldozed to the final 2.2H:1 V slope to reclaim each lift. Please describe the maximum length of slope at any time which will require grading to the final reclamation configuration. Please ensure the bond estimate provided in Exhibit L includes costs for grading this proposed maximum length of slope for the waste rock landform. The maximum length of the WRL during phase 1 mining is shown on Map C-3 and will be 300 feet long as is included in the Exhibit L bond calculation. This distance from the phase 1 finished pad to the phase 1 WRL final surface is <0.5 miles. Subsequent phases will require a bond recalculation that includes updated WRL lengths prior to opening additional phases. 26. Please state the maximum proposed mining depth (in feet) for each mine phase. Every mining bench will be mined to a height of 25'. Total depth is an irrelevant number— compared to a gravel pit, for example—for bonding purposes as the active highwall will not exceed 25'. However, Table 2 now includes the starting elevation, post-mined elevation, and change of elevation for each phase. The delta values were calculated by subtracting the final phase floor elevation from the highest pre-disturbed point of that phase. 27. Please state the maximum proposed height(in feet) of the waste rock landform(s) for each mine phase. Each active lift during any phase of the WRL's development will not exceed 50 feet in height. However, the lift below the active lift will remain ungraded to provide stormwater drainage; therefore, the WRL "highwall" height is limited to two 50-foot lifts or a total of 100 vertical feet. Once each lift is graded to 2.2H:1.OV, said lift is no longer considered a highwall. For the purposes of bonding, full height of the WRL as a whole is not relevant. Additionally, it should be noted that lower lifts in the 'tighter' portions of the drainage will fill much more quickly than upper lifts that occupy a wider portion of the drainage profile. 28. This exhibit refers to potential mine phases 4 and 5 in which the phase 2 and 3 quarries are mined deeper to be utilized as reservoirs. Please commit to one mining plan at this time, either the plan proposed on Figure C-5— End of phase 3 or the one proposed on Figure C-6— End of phase 4 & 5 Reservoir Excavation. This plan can be revised later through the appropriate permit revision. Refer to the Applicant's response to question #7. 29. Please provide the approximate dimensions of all proposed roads and describe how they will be surfaced, if at all (e.g., paved, graveled). Please ensure the reclamation of any roads not proposed to remain for reclamation is addressed in Exhibit E and also in the Exhibit L bond estimate. Details for all roads are featured on Appendix 1 maps. All roads will be graveled and no phase 1 roads will require reclamation for the sake of the Exhibit L phase 1 bond calculation. Therefore, the CCP access ramp and underpass, WRL roads, and road up to phase 2 will NOT require reclamation. December 2021 9 Lewicki&Associates