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that there were 148 instances where two or more holes were detonated <br />within 8 milliseconds or less of each other. The permit states that blast <br />holes will have a 9-ms delay between each of them. <br />The distance between the blast and the Primero School was recorded on the log as <br />5200 feet; information provided later indicated the distance was 3350 feet, <br />contradicting the information on the log. Failing to properly identify the <br />distance between the blast and the school is a violation of Rule 4.08.5(4). <br />The number of persons in the blast crew is not recorded on the log, as required by <br />Rule 4.08.5(16). <br />A calibration signal of the seismograph's gain setting, or a certification of annual <br />seismograph calibration, was not available, as required by Rule <br />4.08.5(17)(a). <br />A record of the distance from the blast to the seismograph was not recorded on <br />the log, as required by Rule 4.08.5(17)(b). <br />A record of the airblast level was not recorded on the log, as required by Rule <br />4.08.5(17)(e). <br />Blast 106-02: <br />The log and the blast sketch indicate that 115 holes were detonated. The pemut <br />States that the maximum will be 72. <br />The log indicates that the blast holes were 24 feet deep. The permit states that <br />that blast holes will be at least 30 feet deep. <br />The log indicates that explosive material was placed in the blast holes to within 8 <br />feet of the surface. The permit states that explosive material will be <br />placed no closer than 10 feet from the surface. <br />The log indicates that the blast was initiated with an electric initiation system. <br />The permit states that initiation will be with anon-electric system. <br />The log and the blast sketch indicate that 17-ms surface delays were used along <br />rows. The permit states that 9-ms delays will be used along rows. <br />The log and blast sketch indicate that 42-ms surface delays were used between <br />rows. The permit states that 100-ms surface delays will be used between <br />rows. <br />The log indicates that 350-ms delays were used downhole. The permit states that <br />600-ms delays will be used downhole. <br />My reconstruction of the blast from the blast log and the blast sketch indicates <br />that there were 105 instances where two or more holes were detonated <br />within 8 milliseconds or less of each other. The permit states that blast <br />holes will have a 9-ms delay between each of them. <br />Rule 4.08.5(11) requires blast logs to have a record of the maximum weight of <br />explosives detonated within any 8-ms interval during the blast. My <br />reconstruction of the blast indicates that the maximum weight of <br />explosives detonated within any 8-ms interval during Blast #106-02 was <br />7641bs/8 ms. The log indicates that the maximum weight of explosives <br />detonated within any 8-ms interval was 570 lbs/8 ms. This indicates an <br />incorrect use of the weight/distance formula of Rule 4.08.4(10)(c)(i). <br />