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100 <br /> 0 <br /> 10 <br /> • <br /> c lip <br /> y50-percentile <br /> > 1 PPV=23.6 SD-1-135 <br /> RZ=0.90 <br /> 1- -- <br /> Y <br /> M 0.38 in/s <br /> a 0.1 • <br /> SD 88 <br /> 0.01 <br /> 1 10 100 1000 <br /> Scaled Distance(ft/lb12) <br /> Figure 1 Peak particle velocity of ground vibration (PPV)versus scaled distance for blast vibration <br /> measurements recorded at four 4 limestone quarries in the western US (Aimone-Martin Assoc.data <br /> base) <br /> was used to predict the highest possible PPV value at the transmission line for the closest blast using the <br /> planned explosives charge weight of 32 lb/delay (information provided by blaster Rusty Bauer). <br /> The approximate distance to the transmission line from the closest blasting is planned to be 500 ft.The <br /> minimum SD is 500/(32)l/z or 88 ft/lb'I'. Using the upper-bound line in Figure 1 at SD=88 the predicted <br /> PPV is 0.38 in/s. <br /> This amplitude of ground vibration results is over 10 times lower than the limit of 4 in/s imposed on <br /> power lines in Pennsylvania and is well within safe levels for towers and lines. <br /> FINDINGS <br /> The power transmission line represents the man-made structure closest to the quarry blasting site at a <br /> distance of 500 ft. This is farther than the 200-ft limit to address stability issues.There will be no-impact <br /> of mine blasting on this power line. <br />