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for over 39 years with explosives utilized for underground mining and safety mitigation <br /> with no areas or structures on or off-site being adversely affected. <br /> Existing Blasting Operations on adjacent Owner's Properties-Aspen Skiing Company, <br /> LLC performs surface and aerial explosions for avalanche mitigation every winter <br /> season as required for public safety. <br /> Notifications-Pitkin County Sherriff dispatch will be notified 24 hours prior to blasting <br /> operations. Neighbor notifications-Aspen Skiing Company LLC will be notified 24 hours <br /> prior to blasting operations. Posting signage-A Blast notification sign will be posted on <br /> the access road to the mine at the permit boundary. <br /> Pre-Blast Survey:A Responsible Person will assess the site conditions and any presence <br /> of Public or Aspen Skiing Company LLC employees on the access road below and in the <br /> vicinity and contact with verbal notice of upcoming operations. A Person will be <br /> stationed at the portal and provide air signal warnings-signal to occur 2 minutes before <br /> the blast and 30 seconds before blast. Blasting days and time will be limited to Monday- <br /> Friday-No Holidays and during the hours of 8:00am-4:00pm, no weekends. <br /> Blasting materials and quantities: 100 grain detonation cord with a detonation velocity <br /> of 23,000 ft/s and 60%strength Gelatin Dynamite with a detonation velocity of 8,000 ft/s. <br /> in small quantities- no more than 20 lbs.per charge. Charge size limit, delay detonator <br /> timing, and proper hole spacing for maximum rock fragmentation size and crack <br /> propagation with minimal explosives will be utilized. <br /> Rock Solid Solutions was retained to estimate the blast vibration given the loading <br /> density and timing described above. See the "Blast Plan & Vibration Predictions <br /> attached, given the 20 lbs. loading density per 8mm per charge timing. Calculated Peak <br /> Particle velocities were well below OSM(Office of Surface Mining) best practices for the <br /> site based upon the "Blast Plan". <br /> No surface vibrations or seismic activity-all blasting operations will be underground <br /> with Peak Particle Velocity limits set at 1.25 inches per second within 300 feet of the <br /> blast, 1.00 inches per second between 300-500 feet of the blast, and 0.75 inches per <br /> second 500-800 feet from the blast. <br /> Blasting Techniques and Procedures: Control blasting and Precision blasting techniques <br /> will be done utilizing-blasting mats-appropriate drilling patterns to ensure safe and <br /> efficient production-more drilling/drill holes and less explosives. Best practices and <br /> safety measures-effective blast designs that enhance underground stability and safety- <br /> mitigation. <br /> Locations of mining Blasting- underground- "A"Station area- 625'from portal/surface- <br /> Number "8"raise- 860'from portal/surface. See Exhibit "E"Mining plan underground <br /> map for specific locations. Proximity to existing structures and structure agreement with <br /> Ski co-see redline underground mining plan with dimensions to portal below. <br />