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indicates that these values appear correct, although 21,973 lbs/115 holes calculates to an average <br />weight of explosives per hole value of 191 lbs/hole. <br />The maximum number of holes detonated within any 8-ms interval during Blast #106-02 is <br />recorded on the blast log as 3. The value for the maximum weight of explosives detonated within <br />any 8-ms interval during the blast is recorded as 5701bs/8 ms, which the log indicates LCC derived <br />by multiplying their value of the average weight of explosives per hole of 1901bs/hole by LCC's <br />value of 3 holes detonated per 8-ms interval during Blast #106-02. <br />By reconstructing Blast #106-02 from its blast sketch, I detemuned that the maximum number of <br />holes that were detonated within any 8-ms interval was 4. Multiplying my calculated value of 191 <br />lbs of explosives hole by my value of 4 holes detonated during any 8-ms interval, I calculated the <br />maximum weight of explosives detonated within any 8-ms interval during Blast #106-02 was 764 <br />(bs/8 ms. <br />My calculated value of the maximum amount of explosives actually detonated per 8-ms interval <br />during Blast #106-02 of 7641bs/8 rns is greater than LCC's recorded value of 5701bs/8 ms. Both <br />values, however, aze less than the State limit of 6112 Ibs/8 ms that I determined to be applicable to <br />Blast #106-02. <br />Rule 4.08.4(10) indicates that for distances from 301 to 5000 feet between blasts and the types of <br />structures described in the rule, the maximum allowable ground vibration at the nearest protected <br />structure, measured as peak particle velocity (PPV), is 1.00 inches per second (ips). The rule <br />additionally indicates that for distances between blasts and protected structures of 5001 feet and <br />greater, the PPV limit is 0.75 ips. <br />The log for Blast #106-02 indicates the distance between the Primero School and the blast was 5600 <br />feet. This would indicate that the maximum ground vibration allowable by Rule 4.08.4(10) would <br />have been 0.75 ips. However, a review of the information provided by Mr. Smith on 6/4/02 <br />indicates the distance between the school and the blast was 4300 feet. Using the smaller distance, <br />the maximum ground vibration allowable by Rule 4.08.4(10) at the Primero School for Blast #106- <br />02 would have been 1.0 ips. <br />According to the log for Blast #106-02, a seismograph was located 1000 feet north of the blast. A <br />check of the seismograph's distance from Blast #106-02, based upon the information provided by <br />Mr. Smith on 6(4102, indicates the distance from the seismograph to the blast was approximately <br />1050 feet. The log indicates that the seismograph recorded a maximum ground vibration level of <br />0.11 ips. <br />According to information provided by Mr. Smith on 5/29/02, the seismograph had a low end <br />frequency of 2 Hz; as such, the maximum level of airblast allowed by Rule 4.08.4(6)(a) at the <br />Primero School would have been 133 dB. According to the log for Blast #106-02, the seismograph <br />used to monitor Blast #106-02 recorded a value of 129.7 dB. <br />