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ENVIRONMENT, INC. PAGE 3 <br />OCTOBER 25, 201 3 <br />This was a misunderstanding. Originally the proposal was to place 30 lbs. of blasting agent <br />in each 3 inch by 18 foot deep hole. This remains unchanged and at not time will 60 lbs. be <br />used in a single hole. The 60 lbs. number came into play in the explanation that during a <br />shot string there may be a time when 2 holes are detonated very close together (8 ms <br />separation) as two lines are sequentially shot. <br />8. The blasting plan states that overpressure will be kept below 134 dB and velocity less than 2 <br />inches per second. Please specify how far from the blast location the above referenced limitation is <br />applicable. <br />Mr. Bradley said that he did not think the above information was presented having the benefit <br />of some of their previous correspondence. For clarity -lake the overpressure number should be <br />133 dB at a point between the closest shot and the nearest house at a point where a straight <br />line from the hole to the house intersects the property line. This is the same point where the <br />seismic monitoring equipment will be located. <br />9. The Division recommends that the Operator conduct a pre -blast survey of all permanent <br />man -made structures which have the potential to be impacted by blasting operations. Please <br />respond. <br />The applicant concurs with your suggestion to the extent possible. They will only be able to <br />do this with cooperation of the permanent man -made structure owners in question. If they are <br />able to do the inspections, the Division will be provided copies for the tile. <br />We will begin to prepare the additions permit Exhibits and submit them to the Division <br />within the time period specified in the emergency order. I will include copies of this filing in <br />that packet as well. If you have more questions please call me. <br />Sincerely, <br />Environment, Inc. <br />�149ZA;2__ <br />Stevan L. O'Brian <br />President <br />cc Colorado Rose Red, Inc. - Caleb Liesveld <br />Bradley Blasting - Jeff Bradley <br />Overlook mine LLC - Ken Evans <br />file <br />enclosure <br />