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<br />CHAPTER 9 <br />COMPLSANCE OPTIONS AVAILABLE 7U THE OPERAIUR <br />GROUND MOTION <br />the OSMRE regulations allow the operator to choose from four <br />optional methods to control ground vibration: <br />1. Section 816.67(d)(2)(i) Maxim~nn Peak Particle Velocity: <br />Providing that each shot is monitored, and a seismograph record is <br />provided, this first option is DISTANCE related, and requires <br />merely that: <br />(a) From 0-300 ft. distance: max. PV = 1.25"/sec. <br />(b) From 301-5000 ft. distance: max. PV = 1.00"/sec. <br />(c) From 5001 ft. to beyond: max. PV = 0.75"/sec. <br />2. Section 816.67(d)(3)(i) Scaled Distance Equation: <br />This method does not require that blasts be monitored, but it <br />relates a permissible MINIMUM SCAI,ID DISTANCE (Ds) to DISTANCE, and <br />requires adherence to these as follows: <br />(a) From 0-300 ft. distance: min. Ds = 50 <br />(b) Fran 301-5000 ft. distance: min. Ds = 55 <br />(c) From 5001 ft. to beyond: min. Ds = 65 <br />3. Section 816.67(d)(3)(ii) Modified Scaled Distance: <br />This is not distance related, but is based upon the collection of <br />site specific data, and the statistical analysis of this data, <br />using the predictive methods covered in the "PRIDICTION AND CONTROL <br />METHODS" Chapter in this manual. <br />4. Section 816.67(d)(4)(i) and (ii) Blasting Lzvel Chazt: <br />This is the most precise, and also the most unrestrictive option <br />available to the operator. It requires the monitoring, recording <br />and analysis techniques that provide complete frequency <br />information, since the vibration limitations imposed, up to 2.0 <br />inches per second, are frequency related. <br />Discussing these options in order, and referring to them <br />throughout this manual, and in Table 4. (Page 61, Instrumentation) <br />as Options 1, 2, 3 or 4, it is possible to detail them, together <br />with their advantages and disadvantages. <br />73 <br />