West Portal Update | 511 Contra Costa

West Portal Update

The installation of pipe canopy on the west portal will be going on until mid January, 2011. The pipe canopy will support the earth above the tunnel during the first 190 feet of excavation.
The next step will be tunnel excavation of the west portal. The tunneling machinery at the West Portal will be smaller, but more versatile than at the East Portal. For more details about the West Portal tunneling excavation check out www.caldecott-tunnel.org.
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