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Exhibit D CMLRB 112 Permil Application Agile Slone $yslems, Inc. • Highwall Access The primary haul road access to the upper benches is north of the plant area, southeast of the plant area going north and an access road in the extreme southeast. The latter road is an exploration road previously bonded by the applicant. Blast Control Plan Scaled distance formulas will and have been used to establish safe seismic disturbances and air blast limits. A blasting vibration study of the site including anticipated ground and air blast levels within 5,000' of the proposed mining site was conducted by Vibra- Tech Engineers, Denver, Colorado (December, 1997). Vibra-Tech performed pre-blast inspections of all structures within 5,000' of the blast zone. The results of these investigations are included with this submittal in the Supplementary Data. The blasting vibration study included a test shot of a single drill hole under confined conditions [hat produced ground wave results estimated to be 200-300% of a production round detonation under normal shot conditions of relief with detonation pressures away from the working face. Thirty seismographs were placed at various distances up to 5,000' from the shot to measure ground wave and air over blast levels. Only the 5 seismographs closest to the shot registered above the minimum 0.03 inches per second wave level necessary to activate the seismographs. Those units placed at and azound the Clazk's residence, 4,350' from the blasting zone, did not register the minimum 0.03 inches per second needed to activate the seismograph. • SCALED DISTANCE TABLE (Peak Particle Velocity 1 inch/second) Maximum Ib explosives Structure Feet from Blast S ms Delay Period State Park 2,750' 2,500 Wootton Residence 3,100' 3,176 ° z. Clazk/Dodd Residence 4,350' 6,255 ° L Clem Residence 5,350' 6,774 b l Blastiug Control Plau In accordance with the Division's request, a Blasting Control Plan has been formulated in conjunction with Fremont County's CUP conditions. "Blasting operations will be conducted in accordance with appropriate industry standards and as prescribed by the Mine Safety and Health Administration. All blasting shall be conducted between the hours of 8:OOAM to 9:OOAM, from Memorial Day to Labor Day, and 10:00AM to 4:OOPM all other days. Blasting shall not occur more than five times per week and shall not occur on weekends or Federal Holidays." CUP 97-1 section l.i. Key points of the applicant's blasting control program include: 1) Apre-blasting inventory of all structures within 5,000' of the proposed blasting . area was completed by Vibra-Tech Engineers, a well known national independent third 19