Construction crews working on the fourth bore of the Caldecott Tunnel will begin constructing the drilling device that will be used to actually bore the hole in the hill. The construction of the drill will take place on the Orinda side of the tunnel beginning this week, so it will be visible shortly.
In addition to the drill, crews will soon be building retaining walls and portal walls. Once all of these items have been constructed, the actual process of boring out the dirt will begin.
Crews have already cleared the hillsides on both sides of the future fourth bore and have constructed sound walls.