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The overburdens and partings are drilled with large blast hole drills with hole diameters <br />ranging from 9 7/8" to 10 5/8". Pattern spacing will range from 15x15 to 30x30 <br />depending on the type and depth of material. Typical drill hole depths will range from 7' <br />to 175' and will be drilled vertical or angled -drilled at 70 degrees. Holes are loaded <br />using a variety of products depending on rock type and wet or dry hole conditions. The <br />charge per delay is based on the "standard scaled distance equation" and the delay <br />time is based on fragmentation and cast results, seismic studies, and frequency <br />response. <br />Coal is typically, drilled and blasted or ripped with dozers before excavation. Generally <br />coal seams over 6' in thickness are drilled with a twin mast auger drill @ 4'/2" diameter <br />on a drill pattern spacing ranging from 10'x10' to 12'x14' and shot at a powder factor <br />ranging from 0.15 to 0.30 lbs/ton. The holes are loaded with packaged explosives and <br />detonated with detonating cord. Surface delays are sometimes used depending on the <br />size of the pattern and number of holes. <br />Limited monitoring of air blast and ground vibration is conducted at a location along the <br />permit boundary to insure that D.R.M.S. Peak Particle Velocity requirements are met. <br />Blasting practices that insure the safety of personnel and equipment will be conducted <br />in accordance with 30CFR Part 77, subpart N. <br />Mining Equipment: <br />Table 1, Major Equipment List, shows the major types of equipment used at Trapper. <br />Table 1, Major Equipment List <br />Equipment Description <br />Page 752LR Draglines <br />Overburden/Parting Drills <br />Track -type Dozers <br />Rubber Tired Dozers <br />Motor Graders <br />Scrapers <br />Hydraulic Excavators <br />Front-end Loaders <br />Cable Reel/Tool Carrier <br />Coal Drill <br />Lowboy Tractor -Trailer <br />240 Ton Haul Trucks <br />95 Ton Haul Trucks <br />50 Ton Haul Trucks <br />ANFO/Blend Truck <br />Number <br />3 <br />3 <br />14 <br />2 <br />5 <br />4— up to 6 seasonally <br />4 <br />3 <br />1 <br />1 <br />1 <br />4 <br />8 <br />4 <br />2 <br />ACCEPTED/FILED <br />AUG 2 6 2016 <br />CMSH-DISTRICT 9 <br />S:\GROUND CONTROLVanuary 2016 GCP Revision\Trapper_ GCP_Jan2016_DRAFTI.docx Page 17 <br />