Laserfiche WebLink
will be stripped and windrowed along the edges of the disturbed areas, so that it can be replaced during <br /> reclamation. It will be seeded to protect it. The access road within the permit will largely remain in its <br /> present location unless a small realignment is required to accommodate the additional drainage and <br /> stormwater controls. (Please see the Exhibit C map showing the locations of these features.) <br /> The new slopes above the expanded quarry highwall resulting from stripping the overburden will initially <br /> be shaped to 3H:1V or gentler. Once they are established, it is anticipated that these slopes will be in <br /> their final location, and they will be reclaimed at this early stage. Topsoil will be placed on the slopes, <br /> and the area will be seeded. (Please see Exhibit E for the topsoil and seeding specifications.) <br /> Initiation of Mining, Benched Highwalls <br /> After all stripping and shaping of the overburden slopes above the planned new highwall margin has <br /> occurred, and the expanded staging and stockpile areas are built, development of the expanded quarry <br /> itself will begin. When the quarry expansion is approved,the operator will be able to increase the area <br /> of the extraction out to the limits of the newly stripped slopes. A benched highwall configuration in the <br /> expanded quarry will be implemented, beginning with extraction in the upper bench and highwall. <br /> A geotechnical stability report was produced by a third party to demonstrate that a steep configuration <br /> of highwalls and benches would be stable. (Please refer to Exhibit S,where the full report may be <br /> reviewed.) Wherever possible,the operator intends to develop the pit essentially to the stated limits of <br /> the obsidian's stability as described in the report:Walls may be a maximum of 30 feet tall and vertical; <br /> the alternating benches must be a minimum of 15 feet wide. This produces an overall maximum slope <br /> of 0.5H:1.OV. (This is shown on the cross-section profiles in Exhibit F.) <br /> Due to the ultimate size of the expanded pit floor and the need to backfill a significant depth in the pit <br /> for reclamation,the operator intends to develop the quarry in three segments,or approximate "thirds", <br /> as indicated by the three "direction of mining"arrows shown on the mining map. This means that,for <br /> example,the benches and walls in the southeast third will be fully developed,and the southeast pit <br /> floor will receive its full depth of backfilled overburden, before the mining in the center third of the new <br /> quarry begins. The reason for these stages of mining and concurrent reclamation is to limit disturbance <br /> and the bond amount. <br /> Drilling and blasting will break the obsidian to allow extraction of the upper highwall deposit while <br /> creating the upper bench. Mined materials will be pushed off the bench down to the pit floor for <br /> processing/sorting. Upon reaching the areal limits of the topmost bench and highwall level of <br /> extraction,the operator will begin the next level. Bench levels will be approximately 30 feet apart in <br /> elevation. Production will proceed with the blasting and removal of the obsidian back to the next <br /> highwall limit, leaving a bench approximately 15 feet wide (sufficient for small-medium equipment to <br /> safely operate). Broken rock will again be pushed down to the pit floor for processing. As the areal limit <br /> of each level is reached,the next deeper level will begin. Each successive level of this expanded quarry <br /> will result in a series of benches in a deeper quarry. <br /> As each one-third stage is completed,the operator will move to the next stage,and begin developing <br /> the next new stage. This will facilitate easier backfilling, reducing mining disturbance,yet allow full use <br /> of the operations pad at the mouth of the pit. <br />