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12. Table D -2 outlines the various stages of mining and reclamation. Please specify if <br />these stages will occur sequentially and indicate at what point during the operation the <br />north platform will be backfilled. <br />Table D -2 has been revised to show the sequence of mining operations. The north platform is <br />mined before the remainder of the quarry is mined further. <br />13. The Mining Plan calls for a continuous slope of 650 on the east side of the quarry. <br />Please describe the mining methods which will be used to create a continuous slope. <br />The mining methods used for the east slope include drilling and blasting at the desired final angle <br />of slope, and then removal of blasted material similar to the rest of the operation. The slopes <br />shown on Maps C -3, C -4, and F are the maximum mined condition. Mining of the east slope <br />may be to as steep as 90 °. <br />It is important to note that the operator may choose to mine at shallower slopes, with variable <br />bench heights and widths. Limits to this variability are shown on Map C -4 Details A and B. <br />These limits are based on the Geotechnical Stability Exhibit. <br />As in Item 6, the reference to a 65° slope has been removed. <br />14. The Mining Plan calls for blasting the basalt to create a series of benches on the <br />western side of the quarry. Please clarify if the benches will require any additional grading <br />in order to achieve the proposed final dimension of the benches. If so, provide detail on the <br />mining methods used to achieve the final grade. <br />The western slope benches are excavated in the following manner: <br />a. Drill rigs drill the blast pattern into the bench, vertically. <br />b. The bench is blasted. <br />c. Some blasted rock is cast into the quarry bottom, and is mucked from there. <br />d. Some blasted rock remains on the slope, and is removed via dozer, front shovel, <br />excavator, and/or front end loader along with haul trucks. <br />e. A new bench is formed by the removal of the blasted rock. <br />All slopes are mined to their final configuration, with the exception of the North Platform. <br />15. Please specify how often blasting is conducted and specify if all of the blasted basalt <br />is removed from the benches before any subsequent blasting is conducted. Also, specify the <br />average volume of material that must be removed from the benches after each blasting <br />event. <br />Blasting occurs 1 -3 times per month, and as needed to generate sufficient basalt for construction <br />material production. Basalt is generally cleared prior to further blasting, as time and equipment <br />permits. The amount of material generated per blast is dependent on the size of the blast, which <br />5 <br />