Tunneling began in summer 2013, just west of the stadiums. In December 2013, Seattle Tunnel Partners stopped tunneling approximately 1,000 feet into the tunnel drive after experiencing increased temperatures in the machine. While investigating the cause of the high temperature readings, Seattle Tunnel Partners discovered damage to the machine’s seal system and contamination within the main bearing. Seattle Tunnel Partners plans to make repairs and enhancements to the machine and resume tunneling in March 2015. The tunnel is scheduled to open to drivers in 2016.