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staging and stockpile areas and build the new stormwater control structures (i.e., earthen dams and <br /> diversions downslope from any disturbed areas). The majority of the large volume of stripped <br /> overburden will be permanently placed in low-profile cells occupying several acres to the north and west <br /> of the quarry area, as shown on the Exhibit C maps. The cells will be shaped to blend with the existing <br /> topography, with slopes not exceeding 3H:1V. <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, expansion of the quarry itself will <br /> begin. The lowest point of the existing quarry floor is only about 15 feet below the elevation of the <br /> existing staging area. When the quarry expansion is approved, the operator will be able to increase the <br /> area of the extraction out to the limits of the newly stripped slopes. A benched highwall configuration in <br /> the expanded quarry will be implemented, beginning with extraction in the upper bench and highwall. <br /> Upon reaching the areal limits of the expanded quarry footprint with the first bench level of extraction, <br /> the operator plans to begin the next level: to deepen the quarry to the next bench, with a new <br /> temporary floor approximately 20 feet deeper. As the areal limit of each level is reached, the next <br /> deeper level will begin; each successive level of this expanded quarry will result in a series of benches in <br /> a deeper quarry, not in a larger quarry. <br /> Under this expansion, a benched configuration of the new quarry highwall will be created, consisting of <br /> walls alternating with level benches. The walls are estimated to be approximately 30(vertical) feet high <br /> with a face of about 1H:2V, and level benches about 10 feet wide or more. The obsidian is a durable and <br /> competent material that is very resistant to erosion and raveling; all raveling rock will be captured by the <br /> benches. The planned configuration will produce a benched highwall that is stable and has an overall <br /> slope of 1H:1V or gentler. The operator plans to spread topsoil on the finished benches so that they can <br /> be revegetated. <br /> Overhead powerlines cross the middle portion of the site, east to west, located in an easement assigned <br /> to Sangre de Cristo Electric (see location on Exhibit C maps). No mining or earthmoving will occur within <br /> the easement or within 200 feet of these structures. Vehicles and equipment will cross underneath the <br /> lines, but due to the commitment of a 200-foot setback,there is no opportunity for any damage to occur <br /> to the structures as a result of any mining or reclamation activity on the site. <br /> All the various types of equipment presently in use on the site will be used in the proposed new plan, <br /> though several of the types may be present in greater numbers than are presently there. Moving large <br /> volumes of overburden, during the short pre-mining stage over these distances, may require teams of <br /> trucks and loaders or scrapers. <br /> In addition to the existing practices of simply extracting and stockpiling the obsidian,there will be new <br /> product markets, and under the new plan the operator will need to crush some of the obsidian to <br /> uniform, specified sizes for the different end uses. This will require that a crusher is also onsite regularly. <br /> It has been observed that water is frequently impounded in the existing quarry. It is expected that this <br /> will continue to be the case, and dewatering will be necessary during all active quarry operations as the <br /> quarry is deepened. Water that is pumped from the quarry(which will be inherently free of sediment) <br /> will be routed to the sediment control/stormwater pond below the toe of the expanded staging area <br /> pad. From there it will either percolate back into the ground or be released into the stream system. <br /> Phase II: The same general steps may be implemented to define and excavate the other large obsidian <br /> deposit in the northern half of the expanded permit area. At this time no details of Phase II are known <br /> or presented in this conversion application, and no disturbance is of that area is being considered at this <br />