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<br />a large slab, from top to bottom, of rock had fallen away from the south east corner of the <br />shot. VJe also quickly noticed that the rock fall had now placed a "completed" loaded and <br />stemmed bore hole that "was" safe, now dangerously close to an "open face". In other ~>~ords, <br />the distance from the powder column to open air was much less than the ntinirnal eight feet <br />that we felt was safe. We both knew that the loaded bore hole was now a potentially <br />dangerous hole in that it would cause uncontrollable fly rock in the horizontal direction due <br />to the now small amount of rock between the explosive column and open air. V/e both <br />looked around and immediatel}' thought of a pit pump in the south end of the pit that could <br />be damaged by any fly rock. We knew the pump should be tnoved. We also felt that 5th <br />Street should be guarded during the shot because of its close proximity to the shot. No other <br />mobile equipment or personnel was observed in [he immediate azea. With that in mind and <br />at approximately 10:15 am, I decided to inform Lance Wade, the Mine Manager and acting <br />day-shift supervisor for that day, the shot was ready and that we had a potential dangerous <br />loaded borehole. I also pointed out to him the close proximity of the pit pump and that we <br />should move it. He informed me that we would wait for the noon time slot to detonate the <br />shot. At 11:00 am., I observed the motor grader operator entering the south end of the pit to <br />remove the pit pump. I went down and assisted him in removing the pump. At 1 1:4> arn, <br />everyone involved with the blast meet for the pre-blast meeting. Lance Wade, Ross Gubka, <br />,lohn King, Cliff Hammon and Mike Hilton were present. The limited amount of burden due <br />to the rock fall on the south-east corner hole was pointed out and discussed. ]t was noted <br />that it was also the first hole in the string to be detonated and that it was pointed to rite south <br />east. Everyone agreed that there was going to be fly rock. It was also discussed about not <br />connecting the hole in question in but that idea was dismissed due to leaving a live i/4 LB <br />cast primer and a sensitive detonator in the muck pile for some dozer operator to acciden[ly <br />Itit and detonate. Pouring water through the already loaded stemming was discussed but eve <br />didn't thinl: the water would soak through the nine feet of stemming enough to desensitize <br />the 400 plus pounds of ANFO in the bore (tole. The guarding plan teas discussed aitd was <br />decided to block both ends of 5th street leading to the Konschak home. Cliff Hammond and <br />Alvin Lewis took up their positions along 5th street. Everyone else took their appointed <br />guarding places. The warning signal was given and the shot was detonated. lmrnediately, <br />there was a lot of fly rock flying in a more or less horizontal plane, heading southeastwardly. <br />Most of it landed within the pit boundaries but an unusually large amount cleared the crest <br />of the pit walls. We were expecting some, but not this large of volume. After the shot was <br />complete and the dust had dissipated, Mike Hilton checked and released the shot area for <br />safety purposes. <br />Post Blast Details: <br />a) Damage and violation assessment. After the all clear signal was given by Mike Hilton. Lance <br />Wade drove around the south end of the pit, looking for evidence of Il}' rock. Ile <br />unmediately noticed a damaged out building and instrumentation panel at the a•.+'er <br />C'data\wlxlaw\rlg\blast412.doc <br />