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A TI Programmable 59 calculator is used i» perform the linear regression <br />analysis. .Results of the data to date indicate a goodness of fit of 75.4% <br />and a standard error of 45.5;x. (For the first six points alone, the 'fit' <br />was 58% and the 'error' 40%). It is obvious what the additional 8 points <br />did to our regression analysis. <br />As the additional data is accumulated, the goodness of fit will continue <br />to improve. ,GEC will cmtlnue to monitor every blast with a VN~ Selstno- <br />'graph. VN~ Ss being retained by GEC to continually up-date the regression <br />curves. <br />CO~YCLUSION <br />The Velocity Attenuation curve and the Distance vs. Charge Weight per <br />De_~ curve show clearly the results of the data and regression study. <br />v <br />The Distance vs Charge Weight per Delay curve is the more helpful so <br />far as blast design is concerned, The curve is based on a scaled distance <br />of 39 and a 95x confidence level (2 standard deviations). <br />Use of the latter curve indicates that 60 lbs./delay can be used at 300 ft. <br />and not exceed 1 inch/sec. velocity. At 500 ft, distance, 160 lbs./delay <br />can be used to stay below 1 inch per second velocity. <br />We recommend use of the subject curve for all future shots at the GEC <br />mine site. The 95% confidence level is good assurance of predictable <br />vibration results an the Dorchester premises. The data are now <br />_ sufficient to support our recomr~endation, <br />