2007-09-11_REVISION - M1997054 (2)

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working down from there. Phase IB will be mined to platform elevation 5800 ft resulting in the bench and highwall configuration consisting of 50 ft wide benches and 40 ft highwalls. Phase II Phase II will continue to Area 2 (drainage 2 east to the northeast comer of the mining limits and south to drainage 3). Benches and highwalls in Area 2 will be developed beginning at the northern and eastern mining limits and proceed inward and down to the platform elevation 5800 ft established in Phase I mining. Benches and highwalls will consist of 50 ft wide benches and 40 ft highwalls. Area 1 previously opened in Phase I will be incorporated in Phase II mining by further excavation to elevation 5700 ft. These benches and highwalls will be 40 ft wide by 50 ft high. Final benches and highwalls above elevation 5800 ft in Area 1 will begin to be reclaimed by backfilling the benches with available overburden or granite crusher fines. Phase III Phase III begins development of benches and highwalls in Area 3 (south side of drainage 3 to the southern corner of the mining limits and ties into Area 2 on the southeastern side of drainage 2). Again, the benches and highwalls will be developed from the outer edges of the mining limits inward and down, with benches and highwalls previously outlined. The area previously opened in Area 2 will be incorporated into Phase IIT mining by further excavation to platform elevation 5750 ft. Final benches and highwalls above elevation 5800 ft in Area 2 will begin to be backfilled. Phase IV Phase IV is the continuation of excavation in all Areas and development of benches and highwalls to the final build-out. Phase IV encompasses the continuation of backfilling and excavation to final elevation 5300 ft. Phase PJ final build-out bench and highwall configurations will consist of 50 ft wide benches and 40 ft highwalls from the highest elevation in the northeast corner of the mining limits down to elevation 5800 feet above sea level. Below elevation 5800, the benches and highwalls will be 40 ft wide by 50 ft high. Actual build-out will vary based on observed highwall performance. Time estimates to complete all mining of the granite is approximately 60 years. Approximately 40% of the granite processing will result in crosher fines, of which 2.2 million cubic yazds will be used for reclamation of the mining slopes for the granite quarry and gravel pit. Mining Methods Rock will be loosened and fragmented by conventional blasting, and then loaded into an in-pit mobile primary crusher(s) with conveyor transport to the main process area. The processing for the granite will be a dry operation. The operator intends to ship rock products by rail primarily, with local deliveries by truck. A railroad currently loops through the gravel plant area and the operator plans a rail spur to the granite quarry. Both are to be connected to the Union Pacific Railroad. The rail road will be relocated in approximately 5 years to remove the existing rail loop for sand and gravel mining activities and lay a track along the northern boundary of the sand and gravel mine (see Exhibit C- 2). The truck traffic will be limited to 24 trucks/day or 85% of the material produced. Front Range Aggregates, LLC- Parkdale Quarry DMG IIZ Permit Amendment Page 16