VIDEO: See how metal workers make enormous girders for Pfeiffer Canyon Bridge Caltrans News Flash » Take this behind the scenes tour at the XKT Engineering Plant in Vallejo, CA, where girders are fabricated for new Pfeiffer Canyon Bridge on State Route 1 in Monterey County. Michelle2017-06-27T14:19:00-08:00June 2nd, 2017|California, Roads, Videos|