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. - <br />applicable standards. Control of flyrock is also important because of it's damaging effect to mining <br />equipment. We observe on a routine basis the effectiveness of controlling flyrock by observing both <br />it's effect on the equipment and areas surrounding the mining disturbance and make adjustments as <br />necessary. Please see Permit section 4.08.4 for a description of flyrock considerations. <br />Item 2.6 -Use of the "Scaled Distance Equation" <br />The original Map 26 and Map 27 were intended to show the relationship between the typical blast <br />designs previously presented in the Permit and the maximum number of such blast holes detonated <br />to meet the Scaled Distance Equation. (Rule 4.08.4(10)(c)(i)). Based upon the scaled distance to <br />the nearest dwelling, all blasts could be modified as necessary with the addition of additional <br />surface delays to meet the ground vibration requirements. We recall that this was the format <br />requested and accepted by the Division in 1981 during the initial Permitting for Colowyo. <br />We understand that the Division now prefers to see a map that shows, not the maximum number of <br />typical holes in an 8 ms period of time, but rather the maximum pounds of explosives allowed in an <br />8 ms period of time. As such, Map 26 has been changed to simply show the maximum pounds of <br />explosives that could be detonated within any 8 ms. period of time, irregardless of the typical blast <br />design presented in the Permit. Since this weight calculation is based on the Equation and has no <br />relationship to type of material blasted, the Map 27 for coal has been eliminated from the Permit and <br />the map pocket will now remain empty. <br />Item 3 - Rule 4.08.2(11 <br />Our original January 15, 1998 TR- 44 submittal included copies of notifications to neighbors <br />regarding opportunities for inspections. Included with those materials was a list of recipients for <br />this notification. Permit section 4.08.2 has been modified to direct the reader to Exhibit 14 of the <br />Permit which provides information relative to this notification requirement. <br />Item 4 -Rule 4.08.4(6 <br />The Rules do not require a minimum frequency for monitoring airblast nor does Colowyo anticipate <br />any minimum frequency for monitoring airblast. We believe the rules do not require a minimum <br />frequency in order to provide flexibility in monitoring based upon site specific conditions. As we <br />have noted in the Permit, Colowyo's isolated location away from nearby structures lends itself to a <br />reduced concern for airblast. Our monitoring for airblast over the past 20 years has been on a <br />random basis and, based upon the data collected, there is no indication of any airblast problems. <br />Colowyo will continue monitoring on a random basis. <br />Item 5 -Rule 4.08.5(71 <br />The Table 5 -Blasting Parameters -Overburden (Typical) has been modified to include the 600 ms <br />down hole delay associated with the 1 pound booster. <br />Item 6 -Rule 4.08.5(31 <br />The Rules do not specify that the Blaster in charge should sign each page of a multi-page blast <br />record. Rather the rules only require one such signature from the Blaster in charge of each blast. <br />As the Division is aware, the blast record is clipped together in our files and the main cover page is <br />signed by the Blaster in charge. The Blaster's signature is valid for the complete report. We <br />believe the Division's request that all pages be signed is redundant and unwarranted . <br />