2009-09-11_REVISION - M1997064 (5)

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The Salt Canyon Project target gypsum deposit lies within the Ustic Torriorthents-Sedillo complex. The primary commodity is cement grade gypsum. Incidental materials, such as overburden or reject material will be used during reclamation to build up the excavation floor for final grading or rebuild slopes if necessary. Based on site exploration, average deposit thickness is 30 feet, ranging in thickness from 19 to 39 feet. Gypsum will be extracted to an anticipated sandstone floor. This will be a dry mining operation. The proposed mine will operate between six to eight weeks each year with mining and processing activities Monday thru Saturday from sunrise to sunset. Mining and processing will be performed by a licensed contractor with oversight by GCC personnel. The site will be developed in phases beginning in the northwest corner of southern gypsum deposit and progressing to the southeast through the deposit. The expected life of the mine is approximately 30 years. Each phase will include an active mining area of ten (10) acres or less and processing/storage area of approximately five (5) acres. The soils and vegetation descriptions provided by Fremont Soil Conservation District remain unchanged from the original approved 110 permit application. Minimal plant growth medium is on site but all will be reserved and used for reclamation. Overburden is approximately zero to five feet deep across the deposit. The northwest end of the southern most ore body contains approximately five feet of overburden, diminishing with progression to the southeast. Using loaders, motor graders, haul trucks and bulldozer, mining will commence in the northwest end of the southern gypsum deposit as a perpendicular cut into the ore body developing both a northwest and southeast mining face. Depending on the depth of overburden, a scraper may be used to manage the overburden. Mining will proceed northwest to the northern extent of the deposit. Attention will then turn to the southeast face, executing the rotational removal and placement of surface material and overburden to reclaim to the northwest. Preliminary mine development will include temporary stockpiling of surface material and overburden, looped haul road and processing area. In order to minimize view shed impact, initial site development will occur in the Preliminary Processing Area, or Phase 1. Surface plant growth medium will be removed and used for temporary reclamation and stormwater erosion mitigation on the existing Western Nutrients disturbance. Gypsum will be mined as a 225 foot wide face proceeding southwesterly perpendicular and approximately 100 feet into the southern target deposit. This initial gypsum removal will develop a 15 to 20 foot bench to the east, providing a visual buffer for mining and processing equipment and stockpiles. Phase 2 or the Northwest Quadrant will relocate the processing and stockpile area into the mine excavation. Mining will proceed from the perpendicular cut to the northwest to the anticipated sandstone floor. Depending on the integrity of the material, 3:1 slopes will be maintained throughout mining by pushing deposit with a dozer onto the mine floor. In the event slope material is too fragile to support equipment, fifty foot benches will be constructed for every 10 foot of vertical face. Page 7 of 34