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• the geophones. The vibration recordings for each of the test shots are found in Appendix <br />N. Distances were surveyed by CC&V. Seismic data was obtained for scaled distances in <br />the range from 10.2 to 78.9. <br />A least squazes linear regression analysis was then performed on the data set to determine <br />the +95% confidence equation as recommended by OSMRE and USBM regulatory <br />guidelines. The statistical validity of the data set is evaluated using the correlation <br />coefficient calculated during the analysis. The equation for the +95% confidence interval is <br />then used to calculate the maximum charge weight per delay period for any given particle <br />velocity and distance. Recommendations are made based on regulatory criteria, accepted <br />citizen tolerance levels, and historic vibration monitoring from existing mine production. <br />RESULTS <br />The regression analysis and scaled distance tables are found in Appendix V. <br />The +95% confidence equation with correlation coefficient calculated from the regression <br />analysis is: <br />PPV =168(SD)-i.s°; r'' =.913 <br />• Given anot-to-exceed peak particle velocity and a distance, the maximum charge weight per <br />delay may be calculated using the equation above. Fora 0.50 inch per second peak particle <br />velocity, the preceding +95% confidence equation yields a scaled distance is 43.8. Tables <br />are attached to the regression analysis in Appendix V using this equation to calculate <br />maximum peak particle velocities based on scaled distance. <br />The equation is in accordance with previous studies that have been performed in the azea. <br />MMC conducted "Ground Motion Attenuation Studies, Ajax and Ridge Road Test Sites," <br />on May 28 & 29, 1997. Vibra-Tech Engineers, Inc. conducted similar studies in the Globe <br />Hill, Ironclad and Cresson mining areas in May 1993. This most recent data set has an <br />excellent correlation coefficient. A high degree of reliability may be placed on these results. <br />CONCLUSIONS <br />The North Cresson analysis recommends a scaled distance of 43.8 in order to not exceed the <br />0.50 inch per second peak particle velocity limit on ground motion created by CC&V <br />blasting operations at the nearest privately owned structures. A high degree of confidence <br />may be placed in the recommended Scaled Distance. The site-specific ground motion <br />attenuation equation can be used to calculate a Scaled Distance for any peak particle <br />velocity. <br />• <br />a <br />