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• The log and blast sketch indicate that surface delays along rows were 25 ms. The permit states <br />that surface delays along rows will be 9 ms. <br />• The log and blast sketch indicate that surface delays between rows were 42 ms. The permit <br />states that surface delays between rows will be 100 milliseconds. <br />• The log indicates that downhole delays were 350 ms. The permit states that downhole delays <br />will be 600 ms. <br />• Based upon my reconstruction of the blast, there were 112 instances of two or more holes <br />detonating simultaneously. There were also 148 instances of two or more detonating within 8 <br />ms of each other. The permit states that all blast holes will have a 9-ms delay between them, <br />and indicates that each blast hole will be detonated sequentially. <br />• The log did not indicate the distance between the blast and the seismograph being used <br />toonitor ground vibration and airblast. <br />• The log did not indicate the level of airblast recorded by the seismograph. <br />Blast#106-02 <br />The log for Blast #106-02 indicates that the blast was initiated at 6:14 am on 5/23/02. Blast #106- <br />02 was additionally linked with a 42-ms delay to Blast #107-02, with Blast #106-02 preceding Blast <br />#107-02, according to the blast logs and blast sketches for these two blasts. The log for Blast #106- <br />02 indicates the distance between the blast and the Primero School was 5600 feet. The information <br />provided by Mr. Smith on 6/4/02 that identifies the location of the blast on a mine map, however, <br />indicates the distance between the blast and the Primero School was 4300 feet, when used in <br />conjunction with LCC Map 2.05.03-4 "Surface Blasting Area" (certified 7/31/01). <br />The distance between Blast #106-02 and the rockfall area is estimated at 5638 feet, based upon the <br />information provided by Mr. Smith on 6/4/02, and my estimate of the location of the rockfall area. <br />The log for Blast #106-02 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 interval during this <br />blast was 10,404 lbs/8 ms. The log indicates that LCC obtained this value by dividing the 5600-foot <br />distance value by the scaled-distance factor from Rule 4.08.4(10) of 55, rounding this value up to <br />102, and squaring this result. <br />LCC's use of the scaled-distance factor of 55 appears 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 #106-02 and the school as 5600 feet. <br />Using my estimated value of 4300 feet, and dividing that value by the scaled-distance factor of 55 <br />as prescribed by Rule 4.08.4(10), not rounding the result, and then squaring the result, I calculated <br />the maximum weight of explosives per 8-ms interval allowed for Blast #106-02 by the State's <br />regulations would have been 6112 lbs/8 ms. This is lower that LCC's calculated value. <br />The log for Blast #106-02 indicates that 21,973 lbs of explosives were used to fill the holes drilled <br />for the blast, that the blast had 115 holes, and that the average weight of explosives per hole was <br />1901bs/hole (21,973 ]bs/115 holes, apparently rounded down). A review of the blast sketch <br />