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The distance between the blast and the Primero School was recorded on the log as <br />5600 feet; information provided later indicated the distance was 4300 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 blast log, as <br />required by Rule 4.08.5(16). <br />A calibration signal of the seismograph's gain setting, or a certification of annual <br />calibration, was not available, as required by Rule 4.08.5(17)(a). <br />Blast 107-02: <br />The log and the blast sketch indicate that 74 holes were detonated. The permit <br />states that the maximum will be 72. <br />The log indicates that the blast holes were 21 feet deep. The permit states that the <br />blast holes would be at least 30 feet deep. <br />The log indicates that explosive material was placed in blast holes to within 8 feet <br />of the surface. The permit states that explosive material would be placed <br />in blast holes 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 initiation <br />system. <br />The log and blast sketch indicate that 17-ms surface delays were used along rows. <br />The permit states that 9-ms surface 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 along <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 62 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 />5700 feet; information provided later indicated the distance was 4500 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 blast log, as <br />required by 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 4.08.5(17). <br />Blast 108-02 <br />The log and blast sketch indicate that 87 holes were detonated. The permit states <br />that the maximum will be 72. <br />The log indicates that the blast holes were 23 feet deep. The permit states that the <br />