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flug 081 06 03:35p TRflPPER MINING <br />~, . <br />August 8, 2006 <br />To: Colorado of Division of Reclamation, Mining and Safety <br />Trapper File 109.2.3.4 <br />From: Jim Phillips~~~ <br />RE: Detonation of Z Pit Misfires during Non-Daylight Hours <br />9708266136 <br />Duririg the night of August 616 at 3:30 a.m. a single pre-split misfire was detonated in the west <br />end of Z-pit. Again, at 2:35 a.m. on August 7`~ a pre-split misfire was detonated. <br />Ttie decision to detonate at these times was that single holes with protruding undetonated cons <br />were discovered on each of the two consecutive nights. These misfired holes posed a definite <br />safety threat to dragline crews working in the area. A very small amount of powder <br />(approximately 120 Ibs) was involved in both cases and it was felt that less cover would have <br />been available had we waited until daylight resulting in a much greater flyrock hazard. The <br />August 6`~ mis-fire had approximately 30 ft of cover and the August 7`" misfire had <br />approximately 20 ft of cover. <br />Due to the amount of burden cover in the undetonated pre-split holes, there was virtually no <br />flyrock from either blast. All the usual safety precautions as spec'rfied in Section 3.4.3 of <br />Trapper's PAP were followed for both of these blasts, including the usual blast warning signals <br />and evacuation of the area by non-blasting personnel. Both blasts occurred without incident. <br />p.3 <br />There were no residences located within one-half mile of the blast locations. Thus, no oral <br />ngtices were required. <br />