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,~ Procedure <br />Ten nine inch diameter drill holes were drilled to a depth of forty to fifty-one feet on <br />thirty foot centers at test site. Attached as Appendix III is a map of the test azea. Each <br />_ drill hole was loaded twenty feet of a 38/62 emulsion/anfo blend resulting in 760 pounds <br />of explosive per hole, primed with one cast booster, and detonated individually. The <br />charge weight was selected to maximize the ground motion created by the explosive <br />detonation while eliminating flyrock and permanent ground displacement. Seismographs <br />were located at varying distances from the test blasts and located on the crop line to <br />maximize ground motion. A map of the test holes and recording locations is attached as <br />Appendix III. Distances, ground motion amplitudes, statistical analysis, particle velocity <br />versus distance tables, charge weight versus distance tables and the complete set of <br />' vibration records are attached as Appendix IV. Individual vibration records are <br />,. summarized by instrument with a table of distance, particle <br />Ground vibrations were measured at distances varying from 165 to 1160 feet from the <br />test blasts. Scaled distances varied from 5.99 to 42.08. Least squares regression analysis <br />was performed on the data set to determine the +95% confidence interval as <br />recommended by OSM and USBM regulatory guidelines. The statistical validity of the <br />data is evaluated using the correlation coefficients calculated in the analyses. The <br />equations for the +95% confidence interval are then used to calculate maximum charge <br />weight per delay interval for any given particle velocity and distance. Recommendations <br />• are made based on regulatory criteria, accepted citizen tolerance levels and historic <br />vibration monitoring from the existing mine production. <br />Results <br />The least squazes regression analyses was performed, and is attached as Appendix IV, <br />contains the regression analysis, tables and seismograph recordings for the Seneca 2-W <br />test site. <br />Individual seismograph records are attached an Appendices V. The records are separated <br />by instrument number. Each set often records is summarized in tabular form on the first <br />page of the record set. The analysis was comprised of these fifty records. <br />The +95% confidence equation and correlation coefficient calculated with the attached <br />data set are: <br />-1.94 2 <br />PPV=477.5*(SD) r =0.914 <br />Where: PPV is peak particle velocity, <br />_• SD is scaled distance, <br />r ~ is the correlation coefficient <br />3 <br />