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RULE 2 PERMITS <br />Approximate blasting patterns for coal and overburden are shown in Table 2.05-4, Blasting Parameters - <br />Overburden (Typical); Table 2.05-5 Blasting parameters - Overburden pre-Split Shot (Typical) and Table <br />2.05-6, Blasting Parameters - Coal (Typical). <br />Colowyo will conduct a timing analysis through various methods for each overburden shot utilizing the <br />down hole delay timing, hole-to-hole delay timing, and row to row timing as applicable to verify the <br />maximum number of holes and thereby pounds of explosive detonated per 8 ms time period. This <br />analysis can be conducted by hand or with computer software that predicts the timing of each hole and the <br />maximum number of holes that will initiate within the prescribed time period. <br />Examples of the maximum pounds of explosives per 8ms period of time versus the distance to local <br />residences and dwellings of concern is reflected on Map 26 - Blasting Analysis Map. Colowyo has <br />historically calculated the maximum weight of explosives detonated with any 8 ms time period by the <br />following means: <br />(Max. no. of holes in an 8-ms) x (Max. lbs. of explosives put in any one hole) <br />The maximum charge weight has been calculated this way to ensure that any blast designed under this <br />criterion would not exceed the allowable amount using the scale distance formula. Thereby, meeting the <br />intent of the law to not exceed the maximum weight of explosives in any 8-ms time period. Colowyo's <br />blast records reflect the maximum weight of explosives using the above method. <br />The typical blasting parameter tables are merely examples of the programs used in blasting coal and <br />overburden at Colowyo. As such, they are not intended to represent any one blast exactly as conditions in <br />the field dictate the exact design for each blast. For example, an overburden blast may be drilled with an <br />offset pattern, 25 feet x 30 feet spacing and tied in row on row rather than the design shown on Table <br />2.05-5. <br />The blast initiation systems that Colowyo uses may vary, but all are noted on the blast report for each <br />blast event. For example one type of blast initiation system is the EZ Dets system. These systems are <br />used to initiate the blast from the certified blaster to the initiation hole and all other holes then tied into <br />that system. An entire initiation system could consist of down the hole caps, delays, and tubing <br />connected to a surface system of cords, delay connectors, and initiation terminal. The system is designed <br />specifically for each blast event to not exceed the requirements of the scaled distance formula or the one <br />hole per 8ms time period requirements. Types of blasting materials and delays to accomplish this are <br />noted on each blast report. <br />Blasting Records <br />Colowyo will keep a record of each individual blast by utilizing report formats shown in Figure 2.05-2 - <br />Blasting Report (coal and overburden), Figure 2.05-3 - Colowyo Chargeweight Sheet (overburden <br />only). <br />These blasting records, along with monthly pit records (hardcopy and electronic copy) can be used- to <br />compile all of the information necessary to recreate the blast and contain the data necessary to comply <br />with Rule 4.08.5. <br />Pre-Blasting Survey <br />Pre-blasting surveys and assessments of surface structures or other structures will be conducted upon <br />request by residents or owners of dwellings located within one-half mile of the Permit Area. A written <br />Rule 2 Permits 2.05-15 Revision Date: 6/23/08 <br />Revision No.: MR-91