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Blasting <br />Colowyo usually engages in blasting of overburden and coal before its <br />• removal. A general sequence for drilling and blasting of overburden and <br />coal will proceed as follows: <br />(1) Establish a drill bench on the overburden. <br />(2) Drill blasting pattern. <br />(3) Load drill holes with explosives. <br />(4) Blast overburden. <br />(5) Remove blasted overburden with shovel, front-end loader, <br />or dragline. <br />(6) Clean coal seam. <br />(7) Drill blasting pattern. <br />(6) Load drill holes with explosives. <br />(9) Blast coal seam. <br />(10) Remove blasted coal with front-end loaders. <br />Colowyo will comply with all applicable state and federal laws in its use <br />of explosives. All blasting operations are conducted by experienced, <br />trained, certified and competent persons. <br />Because of the inherent complexities of the Colowyo mining operation, the <br />surface blasting program has been developed to conform with a variety of <br />coal seams and the diverse overburden handling techniques. The coal <br />blasting will vary from coal seam to coal seam because of the different <br />thicknesses encountered. Three general types of overburden blasting will <br />• be required: one for blasting overburden, one for the pre-spliting of <br />overburden to provide for safer highwalls and one for blasting coal. <br />Approximate blasting patterns for coal and overburden are shown in Table <br />5, Blasting Parameters - Overburden (Typical); Table 5(A) Blasting <br />Parameters - Overburden Pre-Split Shot (Typical) and Table 6, Blasting <br />Parameters - Coal (Typical). <br />Examples of the maximum pounds of explosives per 8 ms period of time <br />versus the distance to local residences and dwellings of concern is <br />reflected on Map 26 - Blasting Analysis Map. <br />The typical blasting parameter tables are merely examples of the programs <br />used in blasting coal and overburden at Colowyo. As such, they are not <br />intended to represent any one blast exactly as conditions in the field <br />dictate the exact design for each blast. For example, an overburden <br />blast may be drilled with an offset pattern, 25 feet x 30 feet spacing <br />and tied in row on row rather than the design shown on Table 5. <br />Blasting Records <br />Colowyo will keep a record of each individual blast by utilizing report <br />formats shown in Figure 2 - Blasting Record (coal and overburden), Figure <br />3 - Hlast Report (Lbs Explosives/ Drill Hole) (overburden only) and <br />2.05-28 <br />Revi~lon SuMutted / s / ~~ 9Y <br />