Wheelbarrows lay foundation for new Majorana lab

Contractor Ainsworth-Benning poured the largest concrete floor in the Davis Campus at the 4850 Level last week. And when the crew was unable to use a pump to move a special low-radiation concrete mix from the underground batch plant to the work site, they turned to an old-fashioned tool: the wheelbarrow.

Sanford Lab Engineering Director Rick Labahn thinks the ?highly angular? limestone in the low-radiation aggregate made pumping difficult. However, the special concrete was required in two sensitive areas of the Davis Campus to help further reduce background radiation. In the Davis cavern, where the LUX dark-matter detector will be installed, the low-background concrete was used to pour the floor for two ?counting rooms? where radiation levels in various experiment components will be measured. The Sanford Lab Operations Department had provided an LHD loader to move the special concrete from the batch plant, which is set up in the nearby Transition Cavern, to the Davis Cavern. Last week, masons began construction of the block walls of the counting rooms.

The special mix also was used last week in the north end of the Transition Cavern, where the Majorana Demonstrator experiment will be installed. The batch plant was only a few yards from this pour, so the Ainsworth-Benning crew moved 60-plus yards of concrete the old fashioned way?by wheelbarrow?to pour a floor that?s a foot thick.

Although a delay of the delivery of the batch plant had pushed the start of concrete work back by two weeks, other work was completed ahead of schedule and the Operations Department continued to stay ahead of the Yates Shaft load schedule. As a result, the overall Davis Campus outfitting project remains on schedule. Of particular note, Labahn says that Ainsworth-Benning?s attention to detail and meticulous housekeeping have contributed to an excellent safety record this summer.