Yates Shaft work deck out, cage in

Installation of the new Yates Shaft conveyance last week was a major step toward providing scientists access to the Davis Campus on the 4850 Level. Sanford Lab facilities technicians, shaft technicians and hoist operators worked closely with the Environment, Health and Safety Department on the project, which has been in the works for more than a year. Building on decades of Homestake experience, the team created procedures to remove the old work deck from the shaft and install the new conveyance?a ?service cage? in Homestake parlance.

The 14,000-pound cage, built by OJ Industries, has a capacity of 10,000 pounds. The design is similar to the old cage, but the interior of the new version is 9 feet tall?big enough to transport the LUX dark-matter detector.

The Yates conveyance will not be ready for regular transport of people until a ?rope dogging? safety system is installed. Additional wire ropes will be installed in the Yates Shaft. If the hoist rope goes slack, the system?s ?dogs? (clamps) automatically grip the dog ropes to safely stop the cage in the shaft.

A crew from Heavy Constructors Inc. is on site this week to begin installing a new tower in the Yates headframe to support the dog ropes, then Sanford Lab technicians will install the ropes themselves. The system will be completed by March, in time for scientists to begin underground installation of the LUX dark-matter detector and the Majorana Demonstrator experiment.

The Yates Shaft also will become the main access to the underground while crews replace steel in the Ross Shaft, which will become the secondary egress route from underground.