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Showing posts from January 25, 2012

Drill Bits and Dynamite...Part Sixteen ....Cut 7 and 8

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Cuts 7 and 8 on the Sea to Sky improvement project were challenging in their own unique ways.  The one tricky bit of cut 7, was the steep side-hill below the cut, that lead directly to the highway below. All the rock that needed to get blasted away from the lower side of the cut...automatically wanted to roll all the way down to the road below. The other part, that was both a blessing and a curse, was that the cut 7 rock was the softest rock on the site. This means a couple of things..one was that the soft rock would jam up the drill bits if you tried to drill too fast. On the other hand...if you had the drill rig all dialed in and paid attention...you could make record time on drilling each blast hole.  The rock on Cut 7 was so soft, that after each blast the 385 excavator would just keep on digging and tearing it's way past the limits of the blast pattern. Instead of drilling and blasting every second day...we would have to wait for the 385 to hit harder rock that was ...