13 July 2015: As excavation progresses on the 3.5 miles of twin running tunnels for the 4.2 mile (7km) Northgate light rail extension for Sound Transit in Seattle, it was the Robbins 6.4m diameter EPBM that recorded the second of six breakthroughs for the two TBMs on the project. The other TBM on the contract for the Jay Dee/Coluccio/Michels JV, the Hitachi Zosen EPBM, recorded the first breakthrough in May this year (2015) and is now into the second of the three parallel drives to the University District Station with the final breakthrough for both machines occurring at the University of Washington and programmed for end of the year for the Hitachi machine and by about March 2016 for the Robbins EPBM. Breakthrough of the Robbins EPBM at the Roosevelt Station box completes the longest section of the twin running tunnels at 8,000ft 2,440m with two drives each of about 5,000ft 1.525m left for each machine to complete.

Snapshot

Robbins EPBM breakthrough on Seattle LRT Northgate Link