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<br />• <br />C~ <br />Vibration records were collected using eleven Instantel Blastmate III and Minimate Plus <br />seismographs. The seismographs record particle velocity digitally in the frequency range of 1.5 to <br />250 Hertz. Each shot is measured in three orthogonal channels of ground motion: vertical, <br />longitudinal, and transverse; and one channel of air-overpressure. Zero-crossings of each of the <br />four waveform components are calculated to determine frequency response. <br />Attached as Appendix I, is an excerpt from the Blastmate Ill User's Manual describing the <br />specifications and function of the instrumentation and record processing. <br />An independent party using shake table, piston phone, and electronics traceable to the National <br />Institute of Science and Technology has calibrated the instruments within the past year. Copies of <br />the calibration certificates for the instruments, geophones, and microphones are also found in <br />Appendix I. in addition, the instrument performs aself--test after each recorded event. This is a <br />check of the geophone's overawing and dampening. The microphone is also checked. <br />It is not possible to alter the vibration recordings or file names in any way, other than the ability to <br />add post event notes. For security reasons, the instrument and software manufacturer (Instantel) <br />will not release any of the programming code to any outside interests for any reason. <br />arNn.un + <br />+ ~I <br />~~ MM]opflane r + <br />L <br />SlenMnl TnruJrmr <br />GmuiM Vm.UOn. <br />V=~NIVI <br />T=Tnnrsrw <br />L = LonplWdnel <br />Ewnl <br />Tha.now.InamuPmM <br />wev.rwn,. atll.a er Iti <br />Lwgnualn.l p.apron. (L; <br />v.~l ubn~ m <br />Tnnav.na p.opnon. (n <br />Figure 3 -Event Monitoring <br />For the Yoast study, the energy source <br />involved the detonation of three overburden <br />shots. The 10-5/8"diameter drill holes were <br />drilled vertically to depths ranging from 39 <br />to 48 feet and were loaded with a blended <br />explosive consisting of 62% ANFO and <br />38% emulsion. The holes were stemmed <br />with drill cuttings. (Please see Appendix II <br />for the shot reports). <br />Figure 3 shows an excerpt from the <br />Blastmate III user's manual and illustrates <br />how the geophone was oriented relative 10 <br />the energy source. Earth was "kicked out" in <br />attempt to get a good solid geophone plant <br />at all recording locations. <br />Special attention was paid to seismograph <br />locations, orientations, and distances from <br />shots in order to limit the data scatter as <br />5 <br />