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• The log indicates that explosive material was placed in the holes no closer than 10 feet from the <br />surface. The permit states that explosive material will be placed no closer than 10 feet from the <br />surface. <br />• The log indicates that the remaining upper portions of the drill holes were filled with drill <br />cuttings. The permit states that the upper portions of holes will be filled with drill cuttings. <br />• The log indicates that the blast was initiated with an electric initiation system. The permit states <br />initiation will bewith anon-electric system. <br />• The log and blast sketch indicate that surface delays along rows were 17 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 and 67 ms. The <br />permit states that surface delays between rows will be 100 ms. <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 two instances of two or more blast holes <br />detonating simultaneously. There were also 50 instances where two or more blast holes <br />detonating within 8 ms of each other. The permit states that all blast holes will have a 9-ms <br />delay between them, and indicates that each blast hole will detonated sequentially. <br />• The log did not indicate the level of airblast recorded. <br />Blast#104-02 <br />The log for Blast #104-02 indicates that the blast was initiated at 4:37 pm on 5/16/02. The log <br />indicates that the distance between the blast and the Primero School was 5300 feet. The <br />information provided by Mr. Smith on 6/4/02 that identifies the location of that blast on a mine <br />map, however, indicates the distance between that blast and the Primero school was 4300 feet, when <br />used in conjunction with LCC Map 2.05.03-4 "Surface Blasting Area" (certified 7/30/01). <br />The distance between Blast #104-02 and the rockfall azea 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 azea. <br />The log for Blast #104-02 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 92161bs/8 ms. The log indicates that LCC obtained this value by dividing the 5300-foot <br />distance value by the scaled-distance factor from Rule 4.08.4(10) of 55, rounding this value down to <br />96, and squaring 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 #104-02 and the school as 5300 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, 1 calculated <br />that the maximum weight of explosives per 8-ms interval allowed for Blast #104-02 by the State's <br />regulations would have been 6112 lbs/8 ms. This value is lower than LCC's calculated value. <br />