2008-04-15_REVISION - M1980244 (309)

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C? After drilling, the blast holes will be loaded with detonators and boosters. The blasting agent will be ammonium nitrate diesel fuel ("ANFO") or emulsified ANFO, which will be loaded into the drill holes directly from a truck. CC&V uses an explosives contractor, Buckley Powder, for mixing and delivering product agents to the mining area. The products are then used to manufacture the blasting products at the site by the explosives contractor (see Drawing C-4 for location of explosives storage area). The blasting agents are mixed on site just prior to placement into the drill hole by Buckley Powder. The explosive agents are then detonated by trained and qualified CC&V personnel. The amount of explosive placed in each drill hole depends on the rock characteristics. The loaded holes are detonated in groups with one group separated from another by an appropriate timing delay. The materials, charges, pattern or spacing, and timing of blasting are all dictated by the type of rock, the size requirements of the ore, the mining equipment, the geology and rock mechanics, characteristics of the mine layout, issued air permits, and the need to control the offsite vibration effect of each production blast. • Blasting and ore control methodology for MLE will be conducted as currently approved by OMLR. CC&V's Blasting Effects Seismic Monitoring Program was re-evaluated under Amendment No. 7, Amendment No. 8, the ECME Technical Revision and as part of the MLE Project. The results of these re-evaluations again indicate that in order to maintain a peak particle velocity ("ppv") below the approved standard of 0.5 inches per second ("ips") for sensitive historic structures, the recommended scaled distance is 43.8 for the North Cresson Mine area, 34.2 for the Main Cresson Mine area, 34 for the East Cresson Mine area, and 47.7 for the South Cresson portion of the Main Cresson Mine area. CC&V will adhere to the recommendations of these reports. Each re-evaluation has confirmed that the monitoring plan is sufficient and the monitoring has confirmed no structural damage to surrounding structures should occur from blasting activities at the Cresson Project. Matheson Mining Consultants ("MMC") has compiled a summary of the blasting monitoring program evaluations and results. That summary is included in Appendix 4 in Volume III. Existing monitoring has verified blasting projections, and operations under the MLE will not negatively impact neighboring communities. CC&V has two existing blast monitors in the City of Victor, one in the unincorporated area of • Cripple Creek & Victor Gold Mining Company Cresson Project Mine Life Extension 5-10