This project was part of the greater JPB effort to electrify all 52 miles of Caltrain from San Francisco to San Jose. Drill Tech was involved in two other projects totaling another $80M as part of this electrification effort. This Tunnel Modification Project specifically consisted of the enlargement and electrification of four existing Caltrain double track train tunnels in the San Francisco and San Francisco area: Tunnel 1 is 1800′ long, Tunnel 2 is 1100′ long, Tunnel 3 is 2360′ long, and Tunnel 4 is 3600′ long. All work was completed during weekend long shutdowns of the train tracks from 7pm Friday night to 5am Monday morning, in efforts to minimize impacts to Caltrain operations during heavy commute windows. All equipment had to be modified significantly to allow for rail access since work was performed on the train tracks.

Drill Tech executed a variety of scopes on all four tunnels, the main scope including the use of a rail mounted roadheader to perform tunnel notching that allowed larger electrified trains to fit a larger envelope and achieve the required additional clearance. Drill Tech installed overhead anchors to hold the future OCS wires into the tunnel liner. At each portal (2 per tunnel; 8 total) a larger steel structure was erected on top of either OCS foundations or micropiles. These OCS Portal structures helped hoist the OCS line running through the tunnels, and the OCS wires and conductor rails were then installed. Naturally occurring asbestos (NOA) was encountered during the drilling of OCS foundations and micropiles at the portals.