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The proposed Phase I expansion of the quarry and staging and stockpile areas will grow from their <br /> present locations to adjacent, undisturbed areas. The extraction area (highwall and pit floor)will <br /> generally grow to the north and east;the staging and stockpile areas will grow to the south and west. <br /> Most of the access road will remain in its present location except where slight realignment is required to <br /> accommodate the additional drainage and stormwater controls. (Please see the Exhibit C map showing <br /> the locations of these features.) <br /> The new slopes above the expanded quarry highwall resulting from stripping the overburden will initially <br /> be graded to not exceed 2H:1V. Some of the stripped overburden will be used to build the expanded <br /> 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 locations of the electric powerlines and the 200-foot setbacks on Exhibit <br /> C maps). No mining or earthmoving will occur within the easement or within 200 feet of these <br /> structures. Vehicles and equipment will pass underneath the lines, but due to the commitment of a 200- <br /> foot setback,there is no opportunity for any damage to occur to the structures as a result of any mining <br /> 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 />