Ross steel below the 300 Level

Replacing the steel in the Ross Shaft requires sophisticated equipment. Custom-made work decks have replaced the Ross cage and north skip. (The "cage" is a conveyance for people and equipment. A "skip' is a conveyance to remove rock from underground.) A smaller Sky Climber lift runs up and down the shaft in a parallel compartment, between the cage and skip compartments. Two blue Gorbel cranes are available to remove old steel and maneuver new steel into place.

But the work isn?t always complicated. Last week, for example, Infrastructure Technician Jerry Hinker used a rubber-coated sledgehammer to inch a pesky ?Divider No. 9? into position. ?They usually slip right into place," Hinker said. No matter. After a few whacks of the hammer, the divider was secured with torque-control bolts. Splines on the bolts break at just the right tension, making inspection easier, faster and more accurate, Engineering Technician Kip Johnson said.

Hinker and three colleagues?crew leader Joe Nonnast and infrastructure techs Loren Larson and Derek Lucero? were working near the 300 Level station last Wednesday, which also made it easier for Multimedia Specialist Matt Kapust to photograph a process that will be repeated over the entire length of the 5,000-foot shaft. 

The Ross Shaft originally was constructed with steel I-beams in 6-foot sections called ?sets.? Crews are removing the old steel, some of which dates from 1934, as they work their way down the shaft. They also add new ground control measures, such as rock bolts, where needed. The new tubular steel construction is based on 18-foot vertical sets. (Note the vertical, gray tubular steel in the photos.) Horizontal tubular steel dividers separate the seven long ?compartments? that run the length of the shaft.

Divider No. 9?s snug fit was all part of a day?s work for the four-man crew, crew leader Joe Nonnast said. Installation of the new steel is becoming more routine as the four-man crews work their way down from the top of the shaft. ?We?re getting into the flow of it,? Nonnast said. Four crews of four technicians each are working around the clock, seven days a week on the project, which is part of the Sanford Lab?s long-range plan for underground experiments a that could run for decades.