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� � �� _ � �`��� �� "L' � <br /> �x 1� ��, � � ._ <br /> MINERAL RULES AND REGULATIONS OF THE COLORADO MINED LAND RECLAMATION BOARD FOR THE <br /> EXTRACTION OF CONSTRUCTION MATERIALS <br /> Permit Application Exhibit S—Permanent Man-made Structures <br /> ENGINEERING EVALUATION OF BLASTING EFFECTS ON THE NEARBY OVERHEAD POWER <br /> TRANSMISSION LINES AT THE TAYLOR PIT QUARRY <br /> SUMMARY OF BLASTING REGULATIONS NEAR OVERHEAD UTILITIES <br /> A survey of vibration standards for blasting near overhead utility lines shows very few references to <br /> specific ground vibration limits to protect transmission line and supporting structures. <br /> The State of Pennsylvania�l� mining and construction blasting code is the only reference to ground <br /> vibration limits in which the peak particle velocity(PPV)at the utility structure is limited to 4 in/s. <br /> Alternatively a minimum scale distance factor of 23 ft/Ibu2 may be used for blast design. <br /> The Office of Surface Mining(OSM) regulations�2�that apply to surFace coal mining require that copies of <br /> the blasting schedule be distributed to all pubbic utilities near planned blasting operations and the <br /> blasting plan must identify all nearby utilities. <br /> New York State Department of Transportation�3�blasting regulations stipulate that construction blasting <br /> operations in the proximity of overhead power lines,communication lines, utility services,or other <br /> services and structures shall not be carried on until the operators and/or owners have been notified and <br /> measures for safe control have been taken.A pre-blast meeting must take place before all blasting and <br /> notification to attend the meeting must be extended to owners of utilities within 200 ft of blasting. <br /> Many state,city,and county regulations simply cite the requirements to control or protect all utilities in <br /> the vicinity of blasting operation. <br /> It is norma/practice to limit vibration to a range from 2 to 4 in/s when blasting near utilities as a <br /> precaution. <br /> PREDICTED PEAK GROUND VIBRATIONS AT THE NEARBY POWER LINES <br /> Vibration measurements taken from analog quarry sites with similar limestone rock were used to <br /> predict the highest possible ground vibration expected at the transmission line for blasting along the <br /> northern boundary of the proposal Taylor Pit quarry.Aimone-Martin Associates, LLC(AMA) has provided <br /> a comprehensive data base of peak particle velocity(PPV)versus scaled distance (or SD computed as the <br /> distance from blasting to seismographs divided by the square root of the maximum explosive charge <br /> weight per time delay)shown in Figure 1. Measurements were taken at four limestone quarries in the <br /> western US. <br /> A best-fit(median)trend line was fit to the data and a parallel trend line constructed to represent the <br /> upper-bound or worst-case PPV values corresponding to SD(blast dashed line).The upper bound line <br />