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Fourth Adequacy Response 112(d)-1 Application, Amended CN-01 <br />Wildcat Mining Corporation May Day Idaho Mine Complex <br />backfilled with rock and soil. The man way entry will be installed with a gate and locked to <br />eliminate unwarranted entry. <br />Adequacy Issue #2 <br />In the Division's third adequacy letter, under adequacy item number 21, the Division indicated <br />additional adequacy issues regarding the proposed blasting plan would be forthcoming. The <br />Division's engineering staff has completed its review of the blasting plan and has identified the <br />following adequacy issues. <br />There is discussion in the permit application submittals of blasting in accordance with the Scaled <br />Distance Equation, but no clear commitment to do so. A clearly worded commitment must be <br />provided to conduct blasting in accordance with the Scaled Distance Equation as follows: <br />The maximum weight of explosives to be detonated within any 8-millisecond period may be <br />determined by the formula W = (D/Ds)2 where W = the maximum weight of explosives, in <br />pounds, that can be detonated in any 8-millisecond period; D = the distance, in feet, from the <br />blast to the nearest dwelling, school, church, or community or institutional building located <br />outside the permit area; and Ds = the scaled-distance factor, using the values listed in the <br />following table. <br />Distance (D) from the Blasting Site (in feet) Scaled-Distance Factor to be Applied (DS) <br />0 to 300 50 <br />301 to 5000 55 <br />5001 and beyond 65 <br />The permit application includes a commitment to conduct vibration monitoring for blasts that <br />detonate more than 220 pounds of explosive per delay period. The blasting review prepared by <br />Terry Morris, PE, that is included in the application recommends that monitoring be conducted <br />for blasts that detonate more than 200 pounds of explosive per delay period. The Applicant must <br />commit to the 200 pound limit as the trigger point for a monitoring requirement. <br />The Applicant must commit to preparation and maintenance of a written record for each blast. A <br />record of each blast, including seismograph reports, shall be retained for at least 3 years and shall <br />be available for inspection by the Division upon demand. The record shall contain the following <br />data: <br />a. Name of the operator conducting the blast; <br />b. Location, date, and time of blast; <br />c. Name, signature, and license number of blaster-in-charge; <br />d. Identification, direction and distance, in feet, from the nearest blast hole to the <br />nearest dwelling, school, church, or community or institutional building not <br />located in the permit area; <br />e. For surface blasts, weather conditions, including temperature, wind direction, and <br />approximate velocity; <br />6/6/2011