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Without knowledge of the approximate location of the blast, I am also unable at this time to <br />estimate the distance between this blast and the rockfall area. <br />The log for Blast #103-02 indicates that LCC determined that the maximum allowable weight of <br />explosives that the State's regulations allowed LCC to detonate within any 8-ms period during this <br />blast was 11,881 ]bs/8 ms. The log indicates that LCC obtained this value by dividing the 6000-foot <br />distance value by the scaled-distance factor from Rule 4.08.4(10) of 55, rounding this value down to <br />109, and squazing this result. <br />LCC's use of the scaled-distance factor of 55 appeazs to have been incorrect, however, as that value <br />is used for distances between blasts and protected structures that range from 301 feet to 5000 feet, <br />and as LCC had estimated the distance between Blast #103-02 and the school as 6000 feet. <br />Using LCC's value of 6000 feet, but dividing this value by the correct value of 65, not rounding this <br />result, and squaring this result, I calculated that the maximum weight of explosives per 8-ms <br />interval allowed for Blast #103-02 by the State's regulations would have been 8521 ]bs/8 ms. This <br />value is lower than LCC's calculated value. My calculated value may change, however, if the <br />location of Blast #103-02, to be forwarded to the Division later this month, indicates that the <br />distance between the blast and the Primero School is less than 5001 feet. <br />The log for Blast #103-02 indicates that 30,2641bs of explosives were used to fill the holes drilled <br />for the blast, that the blast had 82 holes, and that the average weight of explosives per hole was 369 <br />lbs/hole (30,2641bs/82 holes). The blast sketch for [his blast indicates that 83 holes were drilled <br />(and presumably all filled with explosives). By dividing 30,264 by 83 (rather than 82), I calculated <br />the average weight of explosives placed into each hole to be 365 lbs/hole. <br />The maximum number of holes detonated within any 8-ms interval during Blast #103-02 is <br />recorded on the blast log as 3. The value for the maximum weight of explosives detonated within <br />any 8-ms interval during the blast, a value required by Rule 4.08.5(1 I) to be recorded, was not <br />recorded. Had LCC multiplied its recorded value of 369 ]bs of explosive/hole by its recorded value <br />of a maximum of 3 holes detonated per 8-ms interval, it appears that the value of the maximum <br />weight of explosives detonated per 8-ms interval during for Blast #103-02 would have been <br />calculated by LCC to be 11071bs/8 ms. <br />By reconstructing Blast #103-02 from the blast sketch, I determined that the maximum number of <br />holes that were detonated within any 8-ms interval during Blast #103-02 was 4. Multiplying my <br />calculated value of 365 lbs of explosives/hole by my value of 4 holes detonated per any 8-ms <br />interval, I calculated that the maximum weight of explosives detonated within any 8-ms interval <br />during Blast #103-02 was 14601bs/8 ms. <br />My calculated value of the maximum amount of explosives detonated per 8-ms interval during Blast <br />#103-02 of 14601bs/8 ms is lazger than LCC's value of 1107 lbs/8 ms (had LCC calculated this <br />value using the numbers LCC recorded on the blast log). Both values, however, are less than the <br />State limit of 8521 Ibs/8 ms that I determined to be applicable to Blast #103-02. <br />