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As mentioned previously, Rule 4.08.5(17)(a) requires seismograph and airblast records, where required, to contain calibration signals of the seismograph's gain setting, or certifications of annual seismograph calibrations. None of these appeared available. Comparing the log from Blast #106-02 with the requirements of the Lorencito permit, I determined the following: • The blast log indicates that ammonium nitrate was the blasting agent used. The permit states that ammonium nitrate will be used. • The log indicates that 115 holes were drilled for the blast. The permit states that the maximum number of holes per blast will be 72. • The log indicates the holes were 24 feet deep. The permit states that the holes will be 30 to 60 feet deep. The log indicates that the average weight of explosive used per hole was 1901bs. My review estimated the average weight of explosive used per hole was 191 lbs. The permit states that the maximum weight of explosives used per hole will be 7401bs. • The log indicates that the total weight of explosives used in the blast was 21,973 lbs. The permit states that the maximum weight of explosives used per blast will be 54,7201bs. • The Log indicates that the blast holes were drilled with a 7-7(8" drill bit. The permit states that blast holes will be drilled with a 7-7/8" drill bit. • The log indicates that the blast holes were drilled on 16'X 16' pattern. The permit states that the blast holes will be drilled on a 16' X 18' pattern. • The log indicates that explosive material was placed in the holes no closer than 8 feet.from the surface. The pernut states that explosive material will be placed no closer that 10 feet from the surface. • The log indicates that the blast was initiated with an electric initiation system. The permit states initiation will be with anon-electric system. • The log and blast sketch indicate that surface delays along rows were 17 ms. The permit states that surface delays along rows will be 9 ms. • The log and blast sketch indicate that surface delays between rows were 42 ms. The permit states that surface delays between rows will be 100 ms. • The log indicates that downhole delays were 350 ms. The permit states that downhole delays will be 600 ms. • Based upon my reconstruction of the blast, there were no instances of two or more blast holes detonating firing simultaneously. There were however, 105 instances of two or more b1 ast holes detonating within 8 ms of each other. The permit states that all blast holes will have a 9-ms delay between them, and indicates that each blast hole will be detonated sequentially. Blast #107-02 The log for Blast #107-02 indicates that the blast was initiated at 6:14 am on 5/23/02. Blast #107- 02 was additionally linked with a 42-ms delay to Blast #106-02, with Blast #106-02 preceding Blast #107-02, according to the blast logs and blast sketches for these two blasts. The log for Blast 107- 02 indicates the distance between the blast and the Primero School was 5700 feet. The information provided by Mr. Smith on 6/4/02 that identifies the location of the blast on a mine map, however,