Bear Swamp: Cherry Picker

by kfrego

My crew hand drilled and installed hundreds of forty foot rockbolts with jackleg drills during the excavation of the tunnel portals and road cuts at Bear Swamp.  Most of the rockbolts were drilled and installed from a crane basket attached to the rigid boom of a Pettibone 30 rough terrain crane, referred to by the nickname Cherry Picker. The little crane weighed about 40,000 pounds and could get us as high as forty feet to work. The basket was large enough for four men and two drills. The forty foot rockbolts were drilled on an 8 foot by 8 foot pattern from the top of the rock cuts to within 20 feet of the ground. We spent 8 to 12 hours a day in the basket, regardless of weather conditions, to maintain the excavation schedules. We always raced each other when drilling and it was very competitive. Both holes had to be complete before the basket could be moved. If you finished your rockbolt installation first, you had to take a break until the other driller finished.

The terrain was often very rough and we would have to push the cherry picker with a bulldozer to get it into working position. We stacked wood cribbing under the four outriggers to keep the crane stable. Sometimes it didn’t work as planned. We were working about 40 feet high in the corner of a portal rock cut. While swinging to the right the right front outrigger fell off the cribbing. The cherry picker tipped to the right front laying the basket into the corner of the excavation. The left side outriggers were both two feet off the ground. Nothing was damaged, but we were in a precarious position. Blackie, our operator, slowly extended the boom straight out to force the crane back close to level. He would jerk the boom back in slowly. Each time he jerked the boom our basket would slide a couple feet down the rock face. When the tipping got precarious again, Blackie would repeat the procedure. It took a while to get us to the ground and Blackie was sweating profusely. We reset all the cribbing and finished our rockbolts.

The cherry picker gave us a scare while working underground. Three of us were working about 30 feet high in one of the tunnels mounting some instrumentation. We were the only crew in the area. We had half a days work before moving the basket. One of us looked back at the crane and smoke was rolling out of the engine compartment. A small flicker of flame could be seen. Dick, our crane operator, was laid against the cab door sleeping like a baby. We jumped up and down, waved with out flashlights, and banged tools on the boom. All the commotion never bothered Dick a bit. We always made noise and banged things around while working. The flames were two feet high when somebody came walking by and woke up Dick. He got us to the ground safely and after a few spent fire extinguishers the fire was out.

Dick and Blackie were excellent operators……………………….and the cherry picker tested them frequently.

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