In photos: LBNF rebuilds portal for rock transportation system

The pre-excavation work for the South Dakota portion of the Long-Baseline Neutrino Facility reached another milestone. In June, construction workers finished securing the portal of the old tramway tunnel. The tunnel will house the conveyor system that will move about 800,000 tons of rock — excavated a mile underground to create the caverns for the Fermilab-hosted Deep Underground Neutrino Experiment — to its final resting place in the Open Cut, a former open pit mining area. The photo gallery below highlights various stages of this work.

The Homestake mining company had stopped using the tramway tunnel when it ceased mining operations in Lead, South Dakota, in 2002. Today the tunnel is part of the Sanford Underground Research Facility. The LBNF team is now in the process of rehabilitating the tunnel to get it ready for the installation of a conveyor system that will run from the Ross Shaft, exit through the rebuilt portal and extend to the Open Cut (see graphic). When the work is complete, the tunnel will house about 2,300 feet of the 4,250-foot-long conveyor system.

Click on the magnifying glass in the photo gallery below to view photos in full.