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• The following is a table of shot numbers, times and locations: <br />Vibra-Tech <br />Shot # Location CC & V <br />Shot # Date Time <br />1 Ironclad IC 200-26 5/10/93 15:01 <br />2 Ironclad IC 200-27 5/11/93 11:44 <br />3 Globe Hill GH 120-14 5/11/93 16:02 <br />4 Globe Hill GH 120-15 5/12/93 10:59 <br />5 Globe Hill GH 120-15 5/12/93 14:57 <br />6 Cresson Cresson 5/12./93 16:07 <br />All references to blasts in -this report refer to the Vibra-Tech <br />shot number. <br />Seismographs were placed at varying distances from each blast. Peak <br />particle velocities, distance from the blast to the recording <br />location and maximum charge weight per delay period were used to <br />develop site specific ground motion attenuation characteristics. <br />Five production blasts resulted in the collection of forty <br />• seismograph records. This data was compared to the nine vibration <br />records taken at the Cresson area. Data was analyzed by individual <br />area and in total. All analyses are attached as Appendix IV. <br />RESULTS <br />Individual seismograph records are attached as Appendix V. A total <br />of forty-nine vibration measurements were recorded: thirteen at <br />Ironclad, twenty-seven at Globe Hill and nine at Cresson. Linear <br />regressions of the peak particle velocity versus scaled distance <br />were run for each individual area: Globe Hill and Ironclad <br />combined, and all data combined.' All regression analyses are <br />attached as Appendix IV. <br />The data collected in the Cresson area has the highest coefficient <br />of determination or the "best fit" of all the data sets. This is <br />attributed to the collection of the data at similar elevations and <br />because the blast was completely confined. <br />The Globe Hill data set shows the poorest fit of data and the least <br />attenuation of ground motion. This is attributed to data <br />collection at varying elevations, the blasts were lower in <br />elevation than most of the instrument locations. This variability <br />results in conservative maximum particle velocity predictions. <br />• The Ironclad data had the highest degree of ground motion <br />attenuation. That is, the vibrations dissipated at a higher rate <br />than in other areas. <br />__l 3 <br />t <br />__ <br />