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have been 0.75 ips. However, a review of the information provided by Mr. Smith on 6/4/02 indicates the distance between the school and the blast was 3350 feet. Using the smaller distance, the maximum ground vibration allowable by Rule 4.08.4(10) at the Primero School for Blast #105- 02 would have been 1.0 ips. The log for Blast #105-02 does not have a record of the value for the distance between the blast and the seismograph that was used to monitor the blast's ground vibration and airblast. However, based upon the information provided by Mr. Smith on 6/04!02, I estimated that the distance between the blast and the seismograph was 1625 feet. The tog for Blast #105-02 indicates that the seismograph had its ground vibration trigger set at 0.05 ips. According to the log, the ground vibration from the blast was too low to trigger the seismograph. According to the information provided by Mr. Smith on 5/29/02, the seismograph microphone had a low end frequency of 2 Hz; as such, the maximum level of airblast allowed by 4.08.4(6)(a) at the Primero School would have been 133 dB. Nothing regarding the amount of airblast generated by Blast #105-02 was recorded on the log, nor was a seismic trace included with the log. Mr. Smith informed me on 6/4/02 that if the seismograph isn't triggered, the seismograph will not produce an airblast record. 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 calculations. None of these appeared available. Comparing the log from Blast #105-02 with the requirements of the Lorencito permit, I determined the following: • The blast indicates that ammonium nitrate was the blasting agent used. The permit states that ammonium nitrate will be used. • The log indicates that the blast holes were 12 feet deep. The permit states that holes will be 30 to 60 feet deep. • The log indicates that the average weight of explosive used per hole was 27 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 7462 lbs. The permit states 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 a 12' X 12' pattern. The permit states that blast holes will be drilled on a 16' X 18' pattern. • The log indicates that explosive material was placed in the blast holes no closer than 6 feet from the surface. The permit states that explosive material will be placed no closer than 10 feet from the surface. • The log indicates that the remaining upper portions of the blast holes were filled with drill cuttings. The permit states that the remaining upper portions of the blast holes will be filled with drill cuttings. • The log indicates that the blast was initiated with an electric initiation system. The permit states that initiation will be with anon-electric system.