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calculated from the information provided on the records (no loading charts were on file for wet <br />holes). Loading charts do not account for multiple primers, which is a cause of some minor (1- <br />pound) errors. In five of the eight reviews, the maximum amount of explosives detonated in any <br />8-millisecond time period was inaccurate. This was due to two reasons. Sometimes Colowyo did <br />not seem to recognize that holes in adjacent rows were being detonated within a given 8- <br />millisecond time period. Colowyo additionally would at times record the maximum hole load <br />times the number of holes detonated with an 8-millisecond time period (a conservative approach <br />for staying under the maximum allowable). Currently, Colowyo is using a computer program <br />that identifies all holes (even those in different rows) in a blast pattern that are expected to be <br />detonated within an 8-millisecond time period. <br />In summary, the blast indicated with an X was in violation of the rule indicated. <br />Rule Date of Blast <br /> 11/2/02 2/2/03 2/3/03 2/6/03 2/12/03 2/13/03 2/16/03 3/19/03 <br /> <br />Rule 4.08.4(10)(c)(i) X <br />Rule 4.08.5(11) X X X X X X X X <br />Rule 4.08.5(11) X X X X X <br />Rule 4.08.5(17)(a) X X X X X X X <br />~ In addition, Rule 2.05.3(6)(a)(i) and the PAP page 2.05-30. These rules and the PAP limit the <br />size (pounds of explosive) of a detanation within an 8-millisecond time period by formula. The <br />record of the 2/16/03 blast indicated that 2,970 pounds of explosive had been detonated within an <br />8-millisecond time period. The maximum permissible pounds of explosive within an 8- <br />millisecond time period, as calculated by the formula, was 3,303 pounds. The reconstruction <br />concluded that 9,135 pounds had been detonated in an 8-millisecond time period. Had Rule <br />4.08.6(1) (use of a seismograph in lieu of the formula) been in effect instead of Rule <br />4.08.4(10)(c)(i), this blast would have been in compliance; except, the seismograph had not been <br />calibrated within one year. Subsequent calibration indicated that the seismograph record of the <br />blast was fairly accurate. <br />z Rule 4.08.5(11) The application of this rule as described in the PAP requires a record of that <br />information required to determine the weight of explosive per hole, rather than a record of the <br />weight of explosives in each hole. Although nearly complete, the weight of explosives used in a <br />few of the holes of the blasts could not be determined because of incomplete hole depth <br />information (drill logs). Colowyo determined and recorded the individual loadings of holes <br />thought to comprise the maximum amount of explosives detonated within an 8-millisecond time <br />period. In addition, Colowyo recorded the average of this maximum loading and entered it on the <br />blast record. The recorded loadings of six such holes of the 11/2/02 blast matched the <br />reconstructed loadings. The recorded loading of one hole of the 2/2/03 blast was one pound short <br />of the reconstructed loading due to a second primer not included in the Colowyo determination. <br />The recorded loading of one hole of the 2/3/03 blast matched the reconstructed loading. The <br />recorded loading of one hole of the 2/6/03 blast matched the reconstmcted loading. The recorded <br />loading of two holes of the 2/12/03 blast were one pound each over the reconstructed loadings. <br />The recorded loading of 14 holes of the 2/13/03 blast matched the reconstructed loadings. The <br />