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VIBRATECH® <br />REMARKS <br />A map showing the seismograph locations as they relate to the five active pits of Trapper Mining <br />can be found in Appendix A. This map was supplied by Larry Johns, Trapper Mining, Inc. <br />CONCLUSION <br />The data obtained by the seismographs at the three different locations were evaluated and aze <br />presented in several visual graphs found at the end of this report. The air overpressures recorded <br />ranged in levels from 88 dB to 128 dB. While quite noticeable and even azmoying to people the <br />levels are well below the nationally accepted criteria discussed earlier in the report. The factors, <br />which seem to have no correlation to the air overpressures were pounds per delay and total <br />pounds of explosives. There does seem to be a direct relationship between the high air <br />overpressures and the number of holes, atmospheric conditions, and the blasting locations. <br />Respectfully Submitted, <br />VIBRA-TECH <br />Joe Crowno~er <br />A~EIs t Area Manage~~G <br />//'J~' 7 <br />Keven B. Hurd, VP <br />Western Regional Manager <br />/jc <br />10 <br />