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9.0 Blasting Limitations <br />Rule 2.05.3(6)(a)(vii), Rule 4.08.4(6) <br />9.1 Air - Blast. <br />Electric blasting caps, electronic delays, noiseless NONEL or equivalent detonating equipment, <br />and various delay systems will be utilized to reduce air -blast effects and noise. Air -blast will not <br />exceed the limits in Table 2.05.3(6)(a) -1 at the location of any dwelling, public building, school, <br />church, or community or institutional building outside the permit area except at such structures <br />owned by WFC. <br />WFC will conduct periodic monitoring to ensure compliance with air -blast standards. The <br />measuring systems used shall have an upper -end flat- frequency of at least 200 Hz. <br />9.2 Ground Vibration. <br />WFC may use seismograph monitors for homes located within 1000' of the proposed blast <br />location, if additional data collection is needed to help perfect WFC's blast modeling program, or <br />at a resident's request, to record the ground vibrations (in /sec) in the three planes (Longitudinal, <br />Transverse, and Vertical). Where appropriate, these same seismographs will also record the air <br />pressure change (dbL) caused by the blast at the same locations. After each blast, the <br />seismographs are downloaded and the information is printed and analyzed. The information is <br />then used to formulate a new blast scale distance factor as well as to judge the shot as being <br />in /out of compliance. The maximum allowable peak particle velocity limits WFC will use for <br />compliance judgment can also be viewed in Table 2.05.3(6)(a) -1. <br />9.3 Fly -Rock. <br />Rule 4.08.4(8) <br />Stemming is loaded into blast -holes prior to detonation to substantially reduce the occurrence of <br />fly rock. The depth of stemming will be designed such that the fly rock including blasted <br />material traveling along the ground, which may result from blasting operations, shall not be cast <br />from the blasting site more than one -half the distance to the nearest dwelling or other occupied <br />structure, and in no case beyond the area of control or beyond the line of property owned or <br />leased by WFC. WFC uses crushed rock for stemming to control vertical displacement of fly <br />rock. The horizontally displaced spoil however, is allowed to move within the previous pit area <br />and into position against the existing spoil pile. <br />SECTION 2.05.3(6)(a) PAGE - 9 - JULY 2013 <br />M -02 <br />/�7 -Ju/ zoi3 <br />