The third and last piece of stuck tunnel machine Bertha's outer shell was removed Monday, making room for the 4-million pound cutter drive to be hoisted to street level in the next week or two.

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The third and last piece of stuck tunnel machine Bertha’s outer shell was removed around 1 p.m. Monday, making room for the 4-million pound cutter drive to be hoisted to street level in the next week or two.

The piece lifted Monday weighed about 90 tons and took only minutes to be pulled from a 120-foot deep access vault, where the tunnel machine is parked along the Seattle waterfront. Hitachi-Zosen, the $80 million machine’s manufacturer, is paying for the lifts and repairs, including a new bearing and stronger seals.

It’s  likely that prime contractor Seattle Tunnel Partners will seek tens of millions of dollars in compensation from state taxpayers for that work as well as STP’s own costs to dig the vault.  Wet grit penetrated the seals in early December, 2013, contributing to a rapid rise in temperatures at the front of the world-record 57-foot-diameter machine. Bertha also failed to break away dirt at the cutting teeth, so that area is also being adjusted.

STP, prime contractor on the $2 billion tunnel, hopes to restart drilling by August, heading under the Alaskan Way Viaduct toward South Lake Union. The four-lane, tolled Highway 99 tunnel, to replace the aging Alaskan Way Viaduct, is now estimated to open for traffic in late 2017.

The state Department of Transportation’s online update, with links to animations of the repair plan, can be found here.