Daily ops: dewatering and much, much more

Observers outside the project sometimes describe daily operations at the Sanford Underground Laboratory as ?keeping the pumps going,? but that description tells only part of the story.

Dewatering is important, to be sure, and on Friday contractor Hydro Resources pulled the deep-water pipes and pump from Six Winze in preparation for installation of a replacement pump this week. (The water level remains at about the 5600 Level.)

However, the Operations Department also reached another milestone recently: the removal of old, unused power cables from the Ross Shaft. More than two dozen personnel worked on the project, including infrastructure techs, hoist operators and electricians. Work began July 6.  By Sept. 25, the crews had removed 55,440 feet of old cable, ranging from telephone lines to big 12 kilovolt cables that had to be cut with hydraulic tools. Infrastructure techs Rod Hanson, Kyle Ehnes, Doug Sneesby and Dick Goetz were the crew leads on the project, working under Technical Support Lead George Vandine. Technical Support Lead Jim Hanhardt helped the team work through the safe steps for the cable removal. Then they built standard operating procedures and wrote job hazard analyses.

Working in wet conditions in a shaft that?s 5,000 feet deep, the crew removed about 10.5 miles of cable. In April, the same crew completed a yearlong project to remove 8 miles of old pipe from the Ross Shaft, which today is cleaner, safer and ready for structural upgrades in preparation for larger experiments.

Work also continues 4,850 feet underground at the Davis Campus. In the Davis Cavern, forms have been stripped from the recently poured concrete curb that will hold a large water tank for the LUX dark-matter detector. In the nearby Transition Cavern, Tessier?s Inc. continued hanging ducts in the new Majorana Demonstrator lab, and Ainsworth Benning Construction prepped the last section of the mechanical room floor for a concrete pour expected this week.

Up top at the surface laboratory, contractors last week installed a large cryogenic tank and filled it with 12,000 liters of liquid nitrogen, which will be used to cool the LUX dark-matter detector for a test run that will begin next week.

Dewatering, by the way, will continue when the new pump is installed early next week.