2016-07-14_PERMIT FILE - M2016010 (4)

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Blasting Procedure: Blasting Sub Contractor— Hitch Rack Ranch Quarry will use a U.S. Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) licensed third party blasting contractor to conduct all blasting activities onsite. Transit Mix Concrete Company will evaluate qualified Blasting Sub Contractors and will contract with one or more of these qualified vendors to support development and production of the quarry. Blast Pattern Design and Drilling— Personnel at Hitch Rack Ranch Quarry will clear and prepare each area to be drilled and blasted according to the established quarry development sequence. The quarry manager, in consultation with the qualified blasting contractor, will design an appropriate drill pattern to ensure safe and efficient production in a given area of the quarry. This includes the burden and spacing design, hole depth, number of holes, explosive densities, initiation sequencing pattern, stemming and other factors included in general blasting practice. Typical blast pattern designs anticipated are listed below: • 5 in. diameter drill hole with burden and spacing of 11 ft. x 13 ft. • 4 % in. diameter drill hole with burden and spacing of 10 ft. x 13ft. • 4 '/2 in. diameter drill hole with burden and spacing of 10 ft. x 10 ft. • 3 '/z in. diameter drill hole with burden and spacing of 8 ft. x 8 ft. • Hole depth ranges from 10 ft. to 45 ft. including up to 5 ft. of sub drill depending on ground conditions and where the hole is located. • Typically the blast holes will be drilled in a vertical orientation. Holes will be angled as needed to construct the final bench geometry and for specific design features. • The number of holes on each pattern will vary depending on the size of the area cleared and what the current needs of the operation are. Figure 1 below shows the typical blast pattern design layout as it corresponds with the description above of typical blast pattern designs.