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5. Blast Plan <br />5.1 Limits on ground vibration <br /> <br />The maximum ground vibration shall be established in accordance with the maximum peak-particle-velocity <br />limit by the scaled-distance equation and the blasting-level chart. A seismographic record shall be provided <br />for each blast. <br /> <br />• Maximum peak-particle velocity. <br />The maximum ground vibration shall not exceed the following limits at the location of any dwelling, public <br />building, school, church, or community or institutional building outside the permit area. <br /> <br />Distance (D) <br />from blasting <br />site, in feet <br />Maximum allowable peak particle <br />velocity (V max) for ground <br />vibration, inches/second1 <br />Scaled-distance factor to <br />be applied without seismic <br />monitoring2 <br />0 to 300 1.25 50 <br />301 to 5,000 1.00 55 <br />5,001 and beyond 0.75 65 <br />Table 1. Scaled distance factor (Source from Office of Surface Mining Reclamation and Enforcement) <br /> <br />1Ground vibration shall be measured as particle velocity. Particle velocity shall be recorded in three mutually <br />perpendicular directions. The maximum allowable peak particle velocity shall apply to each of the three <br />measurements. <br />2Applicable to the scaled-distance equation <br /> <br /> <br />Scaled-distance equation <br /> <br />The scaled-distance equation, <br />W= (D/Ds) 2, to determine the allowable charge weight of explosives to be detonated in any 8- <br />millisecond period without seismic monitoring; where <br />W= the maximum weight of explosives, in pounds; <br />D= the distance, in feet, from the blasting site to the nearest protected structure <br />Ds = the scaled-distance factor <br /> <br />• Blasting-level chart. <br />Holcim may use the ground-vibration limits in Figure 3 to determine the maximum allowable ground <br />vibration. <br />