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<br />Blasting <br />Colowyo usually engages in blasting of overburden and coal before its removal. A <br />general sequence for drilling and blasting of overburden and 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, or dragline. <br />(6) Clean coal seam. <br />(7) Drill blasting pattern. <br />(8) Load drill holes with explosives. <br />(g) 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 of explosives. <br />All blasting operations are conducted by experienced, trained, certified and competent <br />persons. <br />Because of the inherent complexities of the Colowyo mining operation, the surface <br />blasting program has been developed to conform with a variety of coal seams and the <br />diverse overburden handling techniques. The coal blasting will vary from coal seam to <br />coal seam because of the different thicknesses encountered. Three general types of <br />blasting will be required: one for overburden, one for the pre-splitting of overburden to <br />provide for safer highwalls, and one for blasting coal. <br />Approximate blasting patterns for coal and overburden are shown in Table 5, Blasting <br />Parameters -Overburden (Typical); Table 5(A) Blasting parameters -Overburden pre- <br />Split Shot (Typical) and Table 6, Blasting Parameters -Coal (Typical). As shown in <br />Tables 5, 5 (A), and 6, overburden blast drill holes will typically be the only type of blast <br />drill holes that will contain backfill. If coal blast drill holes or overburden pre-split blast <br />drill holes contain backfill, the depth of the backfill will be denoted on a copy of "Figure 2 <br />Blasting Report". <br />Examples of the maximum pounds of explosives per 8ms period of time versus the <br />distance to local residences and dwellings of concern is reflected on Map 26 -Blasting <br />Analysis Map. <br />The typical blasting parameter tables are merely examples of the programs used in <br />blasting coal and overburden at Colowyo. As such, they are not intended to represent <br />any one blast exactly as conditions in the field dictate the exact design for each blast. <br />For example, an overburden blast may be drilled with an offset patter, 25 feet x 30 feet <br />spacing and tied in row on row rather than the design shown on Table 5. <br />2.05-28 <br />September 20, 2002 <br />RN-04 <br />CF 4.1.1.3 <br />