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Rule 4.08.4(10) indicates that for distances from 301 to 5000 feet between blasts and the types of structures described in the rule, the maximum allowable ground vibration at the nearest protected structure, measured as peak particle velocity (or PPV), is 1.0 inches per second (ips). The rule additionally indicates that for distances between blasts and protected structures of 5001 feet and greater, the PPV limit is 0.75 ips. As the log for Blast #103-02 indicates the Primero School was 6000 from the blast, the applicable ground vibration limit at the school would have been 0.75 ips, assuming the 6000-foot value is accurate. This limit may change, however, if the location of the blast indicates a different value for the distance between the blast and the school. According to the log for Blast #103-02, a seismograph was located 2000 feet north of the blast. As the location of the blast is not yet known, I have yet to verify this 2000-foot value; I am therefore assuming at this time that this value is correct. The log for Blast #103-02 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 Rule 4.08.4(6)(a) at the Primero School would have been 133 dB. Nothing regarding the amount of airblast generated by Blast #103-02 was recorded on the log, nor was a seismic trace included with the log. Mr. Frank 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 calibrations. None of these appeared available. Comparing the log from Blast #103-02 with the requirements of the Lorencito permit, I detemuned the following: • The blast log indicates that ammonium nitrate was the blasting agent used. The permit states ammonium nitrate will be used. • The log indicates that 82 holes were drilled for the blast. The permit states the maximum number of holes per blast will be 72. • The log indicates that the blast holes were 24 feet deep. The permit states holes will be 30 to 60 feet deep. • The log indicates that the average weight of explosive used per hole was 365 lbs. The permit states that the maximum weight of explosives used per hole will be 740 lbs. • The log indicates that the total weight of explosives used in the blast was 30,264 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"bit. • The log indicates that the blast holes were drilled on a 18' X 18' pattern. The permit states that holes will be drilled on a 16' X 18' pattern.